exhaust

[edram454]

have been looking at 3 inch exhaust from the headers on back. I have a flowmaster force II system and no cats. I have no drone but would not mind louder sounds. I found a place that would make me a stainless steel mandrel bend 3 inch system with mufflers (dont know which ones flowmaster two chamber??) for about 1200 or 1300 dollars. This would be with xpipe all custom made.

he then showed me a t-100 aluminum exhaust. It is 1/4 or the weight. It is amazingly light. If anybody wanted his zr1 to lose weight this is at least 100 pounds lighter. He could make me a t-100 aluminum complete exhaust for a little over 2k. It is the lightest exhaust I have ever seen. The complete exhaust, pipes, hangers, mufflers, xpipe is all aluminum and welded and 3 inch. This is a killer exhaust and very high end. am thinking about it. Anybody have a 3 inch exhaust with no cats?? how loud is it?? idle? full open throttle??

ed ramos #3028:)

[KILLSHOTS]

I have headers with no cats and the Corsa system, which is 2.5" diameter but basically straight pipes. It is extremely loud at WOT, so I can imagine the system you're considering would be extremely loud as well.

But hey, the louder the better! Sounds like it would be a nice system if you found the right mufflers.

[Franke]

Schrade just put on a 3 inch with x pipe, headers and I think no cats. He did say in a post earlier that he had some cabin drone with it. Schrade are you there?

[edram454]

what would you do if you had a flowmaster II exhaust system? would you cut away the resonator and put an x pipe? I have no drone but I dont care if I do. I drive it so little that my brief driving sessions must be intense. Or should I leave the resonators and change out the mufflers? I have heard those corsa's with headers and no cats and they sound great. I want more sound. Maybe no resonator and 2 chamber flowmasters??

[edram454]

some people have said that the problem with the flowmaster is the mufflers. too restrictive. Is that true? the resonator appears to be restrictive since both pipes coming off the long tube headers go into one resonator. what does a resonator do??

[USAZR1]

what would you do if you had a flowmaster II exhaust system?


If it were on our 94,it would stay there. I had Jeal headers,no cats,and Flowmasters on my 90 ZR-1 and it sounded great! But,since I have a pair of B&B Fusion mufflers,guess I will put those on the car,,someday.
Find you a set of the first gen B&B exhaust,if you want surround sound in full Technicolor.

[mike100]

A resonator tunes out drone at a certain frequency...it is a little higher up in the rev range, not the drone you get in the hatch lugging the car in 6th gear up hills with a loud muffler set.

My experience is that headers with stock mufflers and no catalysts decibel volume-wise is about the same as a free flowing 3" pipe set with cats.

Did you see any of my posts with the C6 NPP muffler valves I installed? GM, Porsche, and BMW use this device on several cars. It works very well. This way you can run a restrictive, quiet muffler and the second outlet runs a straight shot allowing you to have your cake and eat it too.

[Billy Mild]

Dynomax VT mufflers do that.

[KILLSHOTS]

some people have said that the problem with the flowmaster is the mufflers. too restrictive. Is that true? the resonator appears to be restrictive since both pipes coming off the long tube headers go into one resonator. what does a resonator do??
Marc has said before that the problem with Flowmaster is the resonator. I think the mufflers actually flow quite well by themselves. If you like the tone, you might be fine just hacking those off and using them with your new 3" system.

[XfireZ51]

Dynomax VT mufflers do that.

What the VTs don't do is allow you to turn them on or off. A significant part of the drone is attributable to an AFR that's too fat or rich. And it really gets going when you're in the 55kPa+ region of the fueling(VE) table. The exhaust gets "blubbery". Leaning it out tightens the note. Ever notice how the drone goes away on trailing throttle and a slight decline? But climb the incline with a slight acceleration and it gets obnoxious particularly around 1300-1600rpm.

[Schrade]

Schrade just put on a 3 inch with x pipe, headers and I think no cats. He did say in a post earlier that he had some cabin drone with it. Schrade are you there?

HUH? YOU SAY SOMETHIN'?

http://www.emofaces.com/png/200/emoticons/oldhearingaid.png

You better think twice edramos.

Sounds great from outside. But resonance inside is beyond impressive.

In-cabin drone at low RPM's is HEAVY. It's got to be near the 16Hz range @ low RPM's.

Once I get the water out of the tank, I'll get dB readings for as-is, with cork sheeting in new roof headliner, with more cork sheeting under cargo carpet, and lastly, some type of resonator for 2 x 3" inlet + outlet.

[edram454]

I want to make a change but i don't want a mistake. The flowmaster system is good. there is no drone inside car at any speed. It is probably restrictive and if you want a meaner sound then a different system is required or a modification of the current system is in order. It is a crap shoot as to what to change on the current system. some say the resonator is the problem/ some say its the mufflers?? It would be horrible to cut up the system only to find out the modifications are less than desirable.

The flowmasters sound very good at wot but just not aggressive enough at idle or low speeds. I have seen that flowmaster makes the 44 series and the 40 and the 10. the ten is for race cars and its a one chamber muffler. it sounds ratty and too crude so its not a nice sound. the 40 and 44 series are two chamber desire and sound nice. Maybe that is the ticket??

[mike100]

It would be horrible to cut up the system only to find out the modifications are less than desirable.


Who here hasn't had at least 3 exhaust systems:p. For me it has been about 1 per year.

[edram454]

yeah on my other cars I have bought many exhaust systems. they can get quite pricey. I dont want to make that mistake plus I have no where to keep take off systems. I will wait a while and see what surfaces. I like the sound of the corsa's only with headers and no cats. Hopefully somebody wants to change to another system and sells their corsa.

[KILLSHOTS]

I'm on my 3rd since February! ;)

[KILLSHOTS]

yeah on my other cars I have bought many exhaust systems. they can get quite pricey. I dont want to make that mistake plus I have no where to keep take off systems. I will wait a while and see what surfaces. I like the sound of the corsa's only with headers and no cats. Hopefully somebody wants to change to another system and sells their corsa.
Yeah Ed, I jacked around trying to find a less expensive option. I ended up with stock catted manifolds into straight pipes and it sounded AMAZING! Then I remembered I wanted headers and that would have been FAR too loud with those straight pipes. Like you, I didn't care much about drone at the time. I love the deep sound of B&B but wanted a custom system with an x-pipe and black tips, and the price they quoted me was ridiculous, even though I'm local. In the final analysis, I decided that since I was spending $1400 on a frigging catback (I have the black-tip Corsa...more expensive) I wanted to have it ALL, including no drone. I'm glad I stopped experimenting and spent the money on the only (IMHO) true best-of-both-worlds exhaust system. Hope this helps somewhat. Good luck!

[edram454]

yes it does help. If I want the sound of a headers/no cat Corsa, I need to buy one.


ed ramos #3028

[Schrade]

I want to make a change but i don't want a mistake. The flowmaster system is good. there is no drone inside car at any speed. It is probably restrictive and if you want a meaner sound then a different system is required or a modification of the current system is in order. It is a crap shoot as to what to change on the current system. some say the resonator is the problem/ some say its the mufflers?? It would be horrible to cut up the system only to find out the modifications are less than desirable.

The flowmasters sound very good at wot but just not aggressive enough at idle or low speeds. I have seen that flowmaster makes the 44 series and the 40 and the 10. the ten is for race cars and its a one chamber muffler. it sounds ratty and too crude so its not a nice sound. the 40 and 44 series are two chamber desire and sound nice. Maybe that is the ticket??

I don't at all regret this hardware - my motor is running MUCH cooler with it - there's NO doubt about it. If I could readily put OEM hardware back on and spec it for difference, I would.

But I do want to decrease interior drone here, without getting any restriction back - won't be east to do right...

[XfireZ51]

Who here hasn't had at least 3 exhaust systems:p. For me it has been about 1 per year.

I started out w 1 7/8" Watsons w 3G B+B. DRONE.
Went to headers w MagnaFlow 3" Cat-Back including resonator. Nice exhaust but more restrictive although it still made 399rwhp.
Now my final configuration is headers, SW Xpipe, DynoMax UltraFlows w
NPP Z06 tips and full open on/off switching. This is the exhaust I'm sticking with.

[KILLSHOTS]

I don't at all regret this hardware - my motor is running MUCH cooler with it - there's NO doubt about it. If I could readily put OEM hardware back on and spec it for difference, I would.

But I do want to decrease interior drone here, without getting any restriction back - won't be east to do right...
Hey Schrade, Daryll (GoldCylon) had (probably still has) a Corsa resonator for sale. It's 2.5" but a totally straight-through design. Might be a way to reduce your drone without adding restriction.

[Hog]

Speaking of restriction which causes backpressure. "The 1993MY upgrades included going to an exhaust that reduced backpressure by 2" of hg(mercury) was responsible for 6 bhp of the total power increase" of 20 sae net hp.

When the Engineer responsible for the MY1993 power upgrades (Mr. Graham Behan made the above statements, he uses bhp(brake horsepower). I have no idea if a brake horsepower is the same as a SAE net hp or not. If a BHP=SAE net hp, then the reduction in backpressure by 2" of hg, was responsible for 30% of the 20 sae net hp upgrades for MY1993.

I think that many people swap out exhausts (myself included), because it one of the few ways to completley change the personality of a car. While power increases are often stated as a main reason, in reality the search for the desired audible characteristics are the heart of the matter.

[Schrade]

Hey Schrade, Daryll (GoldCylon) had (probably still has) a Corsa resonator for sale. It's 2.5" but a totally straight-through design. Might be a way to reduce your drone without adding restriction.

Where's Daryll here...

How long is your Corsa resonator there D? What are the inlet and outlet centers in inches? THink it would fit behind my X-section here? (https://lh5.googleusercontent.com/-rac1zrFZ2e8/U3-3CNj9TSI/AAAAAAAAETw/QSlpBSH2p_o/s1024/IMG_6542.JPG)

[Fully Vetted]

have been looking at 3 inch exhaust from the headers on back. I have a flowmaster force II system and no cats. I have no drone but would not mind louder sounds. I found a place that would make me a stainless steel mandrel bend 3 inch system with mufflers (dont know which ones flowmaster two chamber??) for about 1200 or 1300 dollars. This would be with xpipe all custom made.

he then showed me a t-100 aluminum exhaust. It is 1/4 or the weight. It is amazingly light. If anybody wanted his zr1 to lose weight this is at least 100 pounds lighter. He could make me a t-100 aluminum complete exhaust for a little over 2k. It is the lightest exhaust I have ever seen. The complete exhaust, pipes, hangers, mufflers, xpipe is all aluminum and welded and 3 inch. This is a killer exhaust and very high end. am thinking about it. Anybody have a 3 inch exhaust with no cats?? how loud is it?? idle? full open throttle??

ed ramos #3028:)

I'll save you some money. I just took off my 3" Magnaflow system and went with catless Corsa (has got to be the loudest on the planet). Selling the whole system for $400 plus shipping.

http://www.zr1.net/forum/picture.php?albumid=220&pictureid=2641

http://www.zr1.net/forum/picture.php?albumid=220&pictureid=2642


It does drone but I dynoed at 430 to the wheels with this system so it flows very nicely.

[KILLSHOTS]

I'll save you some money. I just took off my 3" Magnaflow system and went with catless Corsa (has got to be the loudest on the planet). Selling the whole system for $400 plus shipping.

http://www.zr1.net/forum/picture.php?albumid=220&pictureid=2641

http://www.zr1.net/forum/picture.php?albumid=220&pictureid=2642


It does drone but I dynoed at 430 to the wheels with this system so it flows very nicely.
Quite possibly, the only sound better than an LT-5 with headers into a catless Corsa system at 7000RPM is the sound of someone saying, "Hey, you want this suitcase full of diamonds?"

[Fully Vetted]

LOL...NO DOUBT! It is an absolute hellacious sound. It sounds more like 10,000 rpms. Absolutely intoxicating...

[1990 quasar blue]

With the Corsa system is it the resonator that reduces the drone? I ask because it is straight through. I thought what really helped the Corsa be drone free was the fact that they only flow through one pipe in the mufflers.

Also I have SSW headers, random tech cats, and a flowmaster force II. I agree it's fairly quiet at cruise and idle but, it absolutely screams over 3500 rpm's. I couldn't imagine going louder. People tell me they can hear it coming 1/2 mile away if I'm getting on it.

[edram454]

I agree with both of you. the catless with headers corsa is the most raucous. That magnaflow is at a good price but I dont like the sound of magnaflow too much. I spoke today with a flowmaster engineer and asked him how I could improve the sound of my force II system. He said not to remove the resonator since this is what takes most of the drone out of the exhaust note. He said in tests conducted by flowmaster that the resonator hardly makes any back pressure and flows nicely. He said that he would change the 60 series mufflers that came with all zr1 force II kits for a series 40 two chamber muffler. He said drone would be only slightly increased but the car would certainly be much louder and especially under wot. I might try that since its only a few hundered bucks with custom tips. flowmasters have no fiberglass stuffing or anything inside that can over time wear out. I have had a few flowmaster systems in various cars and they always wore very well and looked great. the two chamber old school non delta force muffler is loud and sounds like a race car in wot. this may be the trick for less money.

ed ramos #3028

[edram454]

With the Corsa system is it the resonator that reduces the drone? I ask because it is straight through. I thought what really helped the Corsa be drone free was the fact that they only flow through one pipe in the mufflers.

Also I have SSW headers, random tech cats, and a flowmaster force II. I agree it's fairly quiet at cruise and idle but, it absolutely screams over 3500 rpm's. I couldn't imagine going louder. People tell me they can hear it coming 1/2 mile away if I'm getting on it.

Yes. The resonator is key to keeping the drone out. I would not remove it if you don't want drone. I would take out the cats and let that corsa sing!

[KILLSHOTS]

With the Corsa system is it the resonator that reduces the drone? I ask because it is straight through. I thought what really helped the Corsa be drone free was the fact that they only flow through one pipe in the mufflers.

Also I have SSW headers, random tech cats, and a flowmaster force II. I agree it's fairly quiet at cruise and idle but, it absolutely screams over 3500 rpm's. I couldn't imagine going louder. People tell me they can hear it coming 1/2 mile away if I'm getting on it.
The stock exhaust was designed to muffle sound, of course. But it was also tuned to eliminate the inherent resonance baked into our cars. It hits hard in the 1800ish RPM range and again in the 3400ish RPM range. The resonator was tuned to help part of it and the mufflers were tuned to help the other part of it. The exact details don't matter, but to answer your question somewhat succinctly, the Corsa system was designed in much the same way, except with much less restriction. What you have in the Corsa is a system that is somehow as effective at quelling resonance at all RPM as the stock system, but still causes virtually NO restriction. It is quiet at part-throttle but straight-pipe loud at full-throttle. Any exhaust can sound throaty or be "open" but in my opinion, the Corsa is brilliant because it just does everything right.

[edram454]

true but.... the corsa 1300.00 compared with the two 40 series mufflers at 160.00. quite a difference.. might be worth a shot?

[WARP TEN]

The stock exhaust was designed to muffle sound, of course. But it was also tuned to eliminate the inherent resonance baked into our cars. It hits hard in the 1800ish RPM range and again in the 3400ish RPM range. The resonator was tuned to help part of it and the mufflers were tuned to help the other part of it. The exact details don't matter, but to answer your question somewhat succinctly, the Corsa system was designed in much the same way, except with much less restriction. What you have in the Corsa is a system that is somehow as effective at quelling resonance at all RPM as the stock system, but still causes virtually NO restriction. It is quiet at part-throttle but straight-pipe loud at full-throttle. Any exhaust can sound throaty or be "open" but in my opinion, the Corsa is brilliant because it just does everything right.

Chris is right. Over 20-odd years of owning ZR-1s, I tested and used a half a dozen systems and the Corsa was the best aftermarket system for flow (HP), sound and lack of resonance. Designed like the stock system to eliminate the resonance at the two rpm points that our cars really have it. Had Corsas for probably 12-15 years total. However as most of you know by now, I finally went back to the stock 95 system with electric cutouts for racing and just making noise when I want to. Usually run with them about1/3 open, but close them when I come back into our subdivision to appease my wife. Really like the set up. Quiet when I want it (say a long trip) and as noisy as I want other times. Headers, no cats, when open basically a straight through system as the stock resonator has little flow resistance. --Bob

[1990 quasar blue]

The stock exhaust was designed to muffle sound, of course. But it was also tuned to eliminate the inherent resonance baked into our cars. It hits hard in the 1800ish RPM range and again in the 3400ish RPM range. The resonator was tuned to help part of it and the mufflers were tuned to help the other part of it. The exact details don't matter, but to answer your question somewhat succinctly, the Corsa system was designed in much the same way, except with much less restriction. What you have in the Corsa is a system that is somehow as effective at quelling resonance at all RPM as the stock system, but still causes virtually NO restriction. It is quiet at part-throttle but straight-pipe loud at full-throttle. Any exhaust can sound throaty or be "open" but in my opinion, the Corsa is brilliant because it just does everything right.

Thanks Chris. The reason I was wondering was because the guys running the NPP tips on a 3" system with X-pipe all have little to no resonance as long as that one tip on the mufflers stay closed.

Ed, it would seem that the 40 series would be the cheapest way to get more sound. I bellieve they're still aluminum so weight should be similar. Sorry I took this a little off topic.

[KILLSHOTS]

true but.... the corsa 1300.00 compared with the two 40 series mufflers at 160.00. quite a difference.. might be worth a shot?
Certainly true, Ed. I felt the same way, so I started making changes to my stock system. I got a great sound but it was pissing-off-the-neighbors loud, and since my only "mufflers" were the cats, the whole system had to go when I installed headers. Those "experiments" didn't cost me a whole lot, but when I finally decided to spend the dough and install the right system, what I had spent on the experiments ended up wasted money. If I had it to do over again, I'd have gone straight to headers and Corsa and saved some time and money.

[OregonDude37]

I went with the cat back Billy Boat 3" X-pipe exhaust system on my ZR - result was impressive. Although I cannot tell you how much improvement in terms of HP, I can tell you the car feels better under full throttle and although there is substantial drone at certain RPM's, the end result makes me smile! The look from the rear is also impressive.Cost was right at $1,000.

[Paul Workman]

With the Corsa system is it the resonator that reduces the drone? I ask because it is straight through. I thought what really helped the Corsa be drone free was the fact that they only flow through one pipe in the mufflers....*


If you look closely at the Corsa Resonator (specifically) you'll see a circular slot opening in the pipe section near the front of each of the resonator pipes. Like blowing air over the top of a pop bottle, a resonance is generated, dependent on the internal dimensions of the resonator - not unlike a pipe organ.

As it happens, the wave pulses created within the resonator cancel those exhaust pulses of the same frequency - and it occurs at that slot in the through pipe you see in the resonator.

And, IIRC, the mufflers too have (Helmholtz) resonators in them; shorter than the those in the resonator; designed to address the resonance occurring around 34K RPM.

Google "Helmholtz Resonator" for an in depth reading and how it is used for noise cancellation.

[edram454]

It looks like when I do decide to do a change, I will go with a muffler swap from my 60 series flowmaster to an original 40 series old style flowmaster exhaust. I know I will hear a significant difference in agressive tone and rumble. I will keep the rest of my flowmaster system including the resonators to limit drone somewhat. I drove my car today with flowmaster force II system and it is somewhat loud and under wot aggressive but I just want more. I dont drive her much so when I do, I want the looks, the power and the sound, plenty of sound. I should cost my around 400 dollars to swap mufflers and add tips. I cant believe that tips have become so expensive. they average 60 to 100+ bucks. I think this should work. My car is great and sounds good now but with this new setup it will be very impressive sounding. rumpty-thump!!

ed ramos #3028

[KILLSHOTS]

It looks like when I do decide to do a change, I will go with a muffler swap from my 60 series flowmaster to an original 40 series old style flowmaster exhaust. I know I will hear a significant difference in agressive tone and rumble. I will keep the rest of my flowmaster system including the resonators to limit drone somewhat. I drove my car today with flowmaster force II system and it is somewhat loud and under wot aggressive but I just want more. I dont drive her much so when I do, I want the looks, the power and the sound, plenty of sound. I should cost my around 400 dollars to swap mufflers and add tips. I cant believe that tips have become so expensive. they average 60 to 100+ bucks. I think this should work. My car is great and sounds good now but with this new setup it will be very impressive sounding. rumpty-thump!!

ed ramos #3028
Just FYI Ed, when you do this, you will be keeping the most restrictive portion of the Flowmaster system, which is the resonator. Also, since you plan on changing the mufflers, you may experience more drone, as your exhaust was designed as a complete "system" and therefore, Flowmaster probably took the drone characteristics of the LT5 (and the C4, in general) into account. You'll be altering that.

Best of luck with the mods. I hope you find the sound you're looking for!

[edram454]

the flowmaster tech said that the resonator is not that restrictive. He said that in testing that there was not that much difference with or without the resonator. He said that the resonator is in place to change the pitch of the sounds and play them off each other so the noise in the cabin would not be too loud. The resonators are just under the floor in the cabin of the car. The mufflers have baffles inside unlike corsa that is straight through with material around the pipe inside the muffler, maybe it is the muffler where there might be some restriction. The muffler used in the zr1 flowmaster kit is a 60 series muffler. It has 3 chambers so the exhaust gets tossed around quite a bit inside that muffler as noise is bumping off several baffles canceling each other out until it finally exits the muffler. the corsa goes straight through and depends on the material that is wrapped around the perforated pipe inside the muffler to eliminate the noise. Over time, the corsa's material inside the muffler will break down and the exhaust will become louder.

the 40 series is a 2 chamber design so it will be louder and it will have more drone and less back pressure etc.. but it is ok. I believe it will work and its worth the shot. If for whatever reason I don't like it then I will opt for the corsa.

ed ramos #3028

[Schrade]

I just did the first test of drone reduction with the extra-foam / painted top, over glasstop.

I did a recording with each. It was a little quieter with the painted top, and when I played it in a media player with graphic EQ, it IS slightly lower volume.

Next test with cork underlayment under interior cargo carpet area. I don't think it will reduce drone enough more, to take the edge off...

And I can't get over the sound like an exhaust leak. HAS TO be the crossover section. There is no exhaust leaking - of that I'm sure...

[XfireZ51]

I would try some styrofoam or foam over the top of the spare tire so that it deadens any resonance of the hatch floor. Could it be that the spare tire carrier creates a BOOOM Box under the hatch floor?

[Schrade]

I would try some styrofoam or foam over the top of the spare tire so that it deadens any resonance of the hatch floor. Could it be that the spare tire carrier creates a BOOOM Box under the hatch floor?

That's a good idea - have to look into that, when I run pipe wrap further back.........

[alnukem]

I started out w 1 7/8" Watsons w 3G B+B. DRONE.
Went to headers w MagnaFlow 3" Cat-Back including resonator. Nice exhaust but more restrictive although it still made 399rwhp.
Now my final configuration is headers, SW Xpipe, DynoMax UltraFlows w
NPP Z06 tips and full open on/off switching. This is the exhaust I'm sticking with.

I have this same system with the exception of the switch, mine is just controlled by engine vacuum, in low vacuum situations like accelerating, it opens. It is awesome but people tell me it's loud, I guess too many years in the gun business!

[edram454]

finally put the new flowmaster original series 40 on my car. there is a difference in sound especially at idle. car sounds much better and throatier. There is more drone during certain rpms but if it gets too bad I can shift up or shift down and get out of the drone zone. wot is very nice. Not as raspy as the corsa but deep and loud especially out the back. I bought the flowmaster ss dual tips and they look ok. they look like the corsa but it is one into two. I wish they were bigger (3 inch each tip,,two per side) but it doesnt look bad.

Unfortunately I saw where a guy in the corvette forum just listed his used corsa system for 900 dollars after I had already bought the mufflers and tips. You never know. I am satisfied with the outcome and the car does sound much more muscular. I didnt spend 900 either. 77 per muffler and 60 per tip. Not bad.

ed ramos #3028

[WARP TEN]

I would try some styrofoam or foam over the top of the spare tire so that it deadens any resonance of the hatch floor. Could it be that the spare tire carrier creates a BOOOM Box under the hatch floor?
Hi Dom--
Many years ago when I was testing a Power Effects system (lots of resonance!) and researching our resonance problem in general I actually had an acoustical engineer (ironically from Outboard Marine) instrument my car and evaluate the causes and suggest a solution. He developed graphs showing precisely what RPM and frequencies the two main resonance points were and showed calculations required to make a Helmholz resonator for each of the offending frequencies, which of course is what the stock and Corsa systems use.

They also researched whether it might involve something like you mentioned called "cavity resonance". Meaning it is enhanced or diminished by the cabin itself (or maybe the tire carrier?). I had asked because it seemed less with the top off. Their conclusion was that it was not cavity resonance but solely caused by the exhaust and the natural harmonics of the engine. It seemed to be less with the top off only because it was generally noisier with it off and it was therefore not as noticeable. --Bob

[edram454]

anybody have headers, no cats and resonators removed??? maybe looking for more noise. Anybody?? I dont care about drone. dont drive it much.

[XfireZ51]

anybody have headers, no cats and resonators removed??? maybe looking for more noise. Anybody?? I dont care about drone. dont drive it much.

That's my setup. In place of resonator, I'm using the C6Z06 tips with NPP controls. Also using SW Xpipe fully open. But I have tuned most of the drone out.

[edram454]

so you control yours with the adjustable c6z06 tips. If its wide open do you find it unbearable or just loud. I want to make a presence. I dont drive it much but when I do I like to know I am driving something special. I drive a Lincoln Town Car for my daily commute and i love that but I want the polar opposite when I get in my z. I want it to really sing at wot. does yours howl with your tips open at wot?? I am considering adding an x pipe and removing my resonators. It sounds good now but want more at wot.

[XfireZ51]

so you control yours with the adjustable c6z06 tips. If its wide open do you find it unbearable or just loud. I want to make a presence. I dont drive it much but when I do I like to know I am driving something special. I drive a Lincoln Town Car for my daily commute and i love that but I want the polar opposite when I get in my z. I want it to really sing at wot. does yours howl with your tips open at wot?? I am considering adding an x pipe and removing my resonators. It sounds good now but want more at wot.

Mike100 has a greater range of adjustment for the Z NPP tips. Mine is setup where I can turn them open or closed. Normally I drive w them closed but when I drive by a "ricer" I flip a switch in the console and blast both tips. If I am in a competitive situation I flip the switch and I have open exhaust. The tips are on DynoMax UltraFlow w 3" inlet. Frankly it's pretty amazing how the exhaust sounds w no resonator. WOT sounds like an old Quadrajet carb opening up. Not at all raspy like the Corsa. It has a very low deep note sounding a bit like a big block.

[alnukem]

anybody have headers, no cats and resonators removed??? maybe looking for more noise. Anybody?? I dont care about drone. dont drive it much.

They say the old B&B triflow with x-pipe is the loudest! Or, you could use any system & electric cutouts.

[KILLSHOTS]

anybody have headers, no cats and resonators removed??? maybe looking for more noise. Anybody?? I dont care about drone. dont drive it much.
As I mentioned earlier, I tried this deal where I continued to adjust the exhaust again and again and again, thinking that each incremental adjustment was inexpensive and therefore, it wasn't costing me anything. It never panned out. The final result sounded good but there was too much drone and I couldn't leave the house early in the morning without pissing off the neighbors. I found that you can't "have it all" without biting the bullet and investing in the expensive system...that one that has had countless R&D dollars dumped into it.

Ed, I wish you luck in your search and I hope you find the magic combo that nobody else has ever found.

[edram454]

I understand and you are right. I had already invested in the mufflers and tips when somebody posted a used corsa for 900 in the corvette forum yesterday. I was already stuck so I installed today. The good thing is that I hardly ever drive my car. Maybe once every two weeks. I cant see my neighbors complaining too much since I am not driving it that much. I am now considering resonator removal with x pipe or electronic cutouts. the cutouts dont seem too bad. I can have the muffler shop weld it in place and I can go home and get the wiring done. Just another possibility. That system will give me the flexibility to be very very loud or as loud as I am now. I am leaning toward these cutouts. we'll see. Thanks for your advice.

ed ramos #3028

[USAZR1]

I found that you can't "have it all" without biting the bullet and investing in the expensive system...that one that has had countless R&D dollars dumped into it.

Ed, I wish you luck in your search and I hope you find the magic combo that nobody else has ever found.


That would be the B&B Fusion catback system,right? ;) Ed isn't looking to "have it all",Chris. He wants a loud exhaust. Drone doesn't seem to bother him,either.
Sounds like an easy man to please.

[KILLSHOTS]

That would be the B&B Fusion catback system,right? ;) Ed isn't looking to "have it all",Chris. He wants a loud exhaust. Drone doesn't seem to bother him,either.
Sounds like an easy man to please.
Hey Clint,

My comment had to do with the fact that Ed had just installed his new Flowmasters and then only a few hours later, was asking if any other guys were running...?

[Schrade]

anybody have headers, no cats and resonators removed??? maybe looking for more noise. Anybody?? I dont care about drone. dont drive it much.

If you don't care about drone, then find some PE's, like I got from Jeff. The SPL, in dB's, HAS TO be 3 figure range. Ironically, it doesn't seem very loud at all, listening as my neighbor drove off around the block, after the last bolts were tight. I think Jeff might still have the link posted to the boards here... (in a moment here)
Jeff does still have his video on 'Public' setting here... (http://s446.photobucket.com/user/2manyvettes24/media/Power%20Effects%20Exhaust/ZR-1PowerEffectsClosed_zps10cc28f4.mp4.html?sort=3&o=2)

I'd have guessed, NOT from experience, that this hardware has more drone than any other aftermarket pipes. And now it seems that Bob WT has qualified that guess.

If mine wasn't running so much cooler, I think I'd have been looking for different hardware.


edit:
And I think mike100 said that drone could probably be reduced with a single outlet open, as opposed to both outlets, each side.

I can't see that reducing drone, but he knows more than me, so I won't argue.

[Paul Workman]

edit:
And I think mike100 said that drone could probably be reduced with a single outlet open, as opposed to both outlets, each side.

I can't see that reducing drone, but he knows more than me, so I won't argue.

Um, yeah... THAT is what all the chatter about the NPP's has been about for quite some time now doanchaknow?? Where ya been??:razz:

[XfireZ51]

Um, yeah... THAT is what all the chatter about the NPP's has been about for quite some time now doanchaknow?? Where ya been??:razz:

Chuck,

I posted this video earlier this year showing the difference between full open and closed for the NPP actuators. Makes a significant difference, maybe 40% less

Here's the video again

http://i187.photobucket.com/albums/x198/Z51Xfire/th_IMG_0887_zps8f8c4c9a.mp4 (http://i187.photobucket.com/albums/x198/Z51Xfire/IMG_0887_zps8f8c4c9a.mp4)

[Schrade]

Chuck,

I posted this video earlier this year showing the difference between full open and closed for the NPP actuators. Makes a significant difference, maybe 40% less

Here's the video again

http://i187.photobucket.com/albums/x198/Z51Xfire/th_IMG_0887_zps8f8c4c9a.mp4 (http://i187.photobucket.com/albums/x198/Z51Xfire/IMG_0887_zps8f8c4c9a.mp4)

Thanks; will give it a listen shortly here...

Does it change INSIDE, and outside sound? Or just outside? Can you get a sound meter on it?

I don't have one; I'm using a camcorder recording, played on a media player with an EQ. Problem with that is, is that the lower band on the EQ is still above the level of the drone - I'm guessing drone (interior resonance) is below 20 hertz, which is normal lower end of human hearing. Normal audiometer won't even do this...

[mike100]

On mine there is still drone at 1900-2000 rpm if you dwell there, but is quite a bit lower than with all 4 outlets trumpeting. If I had chosen a more restrictive muffler like some typical turbo muffler, I'm sure the result would have been even quieter. As it was, the SW 3" system is crazy loud without any resonator, NPP help, or acoustic gimmicks.

A guy on the other forum showed his 25.5 inch 1/4 wave resonator tubes built into the spare tire area. My guess is that's pretty much the same length as a Corsa resonator. Closing off one outlet of the muffler creates a much shorter acoustic reflection that attenuates other frequencies, but it also forces the gas to flow through the more convoluted part of the muffler lowering the amplitude of the sound somewhat just by not being a straight pipe outlet.

[Schrade]

You got vids posted of your hardware's sound too there Mike?

[XfireZ51]

Thanks; will give it a listen shortly here...

Does it change INSIDE, and outside sound? Or just outside? Can you get a sound meter on it?

I don't have one; I'm using a camcorder recording, played on a media player with an EQ. Problem with that is, is that the lower band on the EQ is still above the level of the drone - I'm guessing drone (interior resonance) is below 20 hertz, which is normal lower end of human hearing. Normal audiometer won't even do this...

It changes both. Not sure what muffs mike100 is using, but the DynoMax are straight thru. Flows 2000SCFM. If there is any resonance it is in the 1200rpm range. Anything above that not an issue. That video was shot w a iPhone.

[XfireZ51]

Here's probably a better video showing the difference between open and closed actuators and what exhaust sounds like both ways.

http://i187.photobucket.com/albums/x198/Z51Xfire/th_Z06Tips.mp4 (http://i187.photobucket.com/albums/x198/Z51Xfire/Z06Tips.mp4)

[Schrade]

Sounds reasonable from outside... But so does mine.

I don't have cutouts to seal off (or open even, if they would muffle the drone).

I got some more sections wrapped and clamped. (minus the clamp marking tape)

https://lh5.googleusercontent.com/-kndPlmrGYXg/U_U9J5Z8NkI/AAAAAAAAEvY/EH5ginxYtzc/s640/IMG_6678.JPG

Those straight sections might take sheet cork, with another layer of wrap, once I put an IR thermometer to them...

Next, leftover wrap onto the tail sections at the muffler, then the spare tire space.

Anyone ever open the PE mufflers?

[edram454]

thanks for all your comments on exhaust. In the beginning I was trying to be prudent with my exhaust and accepting my flowmaster system as just fine. It is a good exhaust but... if you want more sound changes need to be made. After i changed mufflers I realized that it still was not enough sound and the drone was not that bad. I wanted more.. Now I am all in on maximum noise.

I want my zr1 experience to be wild and out there. I want the look, the performance and the sound. Most guys say.. what is so special about that lt5 motor?? I want them to hear me coming. When I punch it I want them to hear ther revs in full blast mode. Like I have said before, I dont spend alot of time driving around my zr1. When I choose to drive it I want it to fill my senses so it will last me till next time. I really like to drive alone just so I can take it all in and enjoy my drive. this is a very selfish hobby on my part but I dont care. I worked for it and now I want to enjoy it. My wife understands. The first two did not and that is why they are ex's. I thought about the electric cutouts and I decided I just dont want more electronics on my car. It has enough. I will install an x pipe and remove my resonators and hope it has the raucous sound I want.

ed ramos #3028

[KILLSHOTS]

thanks for all your comments on exhaust. In the beginning I was trying to be prudent with my exhaust and accepting my flowmaster system as just fine. It is a good exhaust but... if you want more sound changes need to be made. After i changed mufflers I realized that it still was not enough sound and the drone was not that bad. I wanted more.. Now I am all in on maximum noise.

I want my zr1 experience to be wild and out there. I want the look, the performance and the sound. Most guys say.. what is so special about that lt5 motor?? I want them to hear me coming. When I punch it I want them to hear ther revs in full blast mode. Like I have said before, I dont spend alot of time driving around my zr1. When I choose to drive it I want it to fill my senses so it will last me till next time. I really like to drive alone just so I can take it all in and enjoy my drive. this is a very selfish hobby on my part but I dont care. I worked for it and now I want to enjoy it. My wife understands. The first two did not and that is why they are ex's. I thought about the electric cutouts and I decided I just dont want more electronics on my car. It has enough. I will install an x pipe and remove my resonators and hope it has the raucous sound I want.

ed ramos #3028
Hey Ed,

Does your car have headers? Before I went to the Corsa system, I had straight pipes...the stock '90 manifolds with cats ran into the stock ZR-1 exhaust pipes, with the resonator replaced by an H-pipe and the mufflers replaced by LT1-tip muffler eliminators. The only "mufflers" were the stock cats. I LOVED, absolutely LOVED the sound the car made and I highly recommend it. It sounds like it may be the sort of sound you want. The only reason I changed to my current setup is because I wanted headers and I knew when I did that, I'd have no "mufflers" at all and I'd be pissing off the neighbors and getting tickets. That's why I got the Corsa when I did headers. If you have stock manifolds and want AWESOME, cheap sound and don't care about drone, I highly recommend straight pipes. Jon Porter (Rex Ruby) will tell you the same thing.

Good luck!

[edram454]

Yes Chris I have headers. The only mufflers I have besides the resonators is the two chamber flowmaster pieces. I expect a good sound without the resonators. I will have them installed next week. A good sound is something that is not very easy to attain. Most exhaust systems dont have that real mean sound because it needs to appeal to the masses. I am sure your exhaust using the cats as the mufflers sounded great but like you said you wanted the benefits of long tube headers for performance gains. I think I will get that sound since headers are loud and no resonators makes the system louder with a higher pitch and some crackling. cant wait.

[mike100]

You got vids posted of your hardware's sound too there Mike?

I posted the entire process at the other forum, but you saw it here first (2-3 months ago) if you are a member and get the newsletter.

here's the video link where the audible resonance can actually be heard by my camera mic.
http://vid29.photobucket.com/albums/c265/mschrameck/exhaust%20system%20clips/MOV02832_zps97199d80.mp4

[mike100]

... I will install an x pipe and remove my resonators and hope it has the raucous sound I want.

ed ramos #3028

I x-piped a stock pipe and muffler set and while still quite pleasant compared to some sets out there, it definitely got more grumble. If headers, x-pipe, no cats, and flowmasters aren't loud enough for you, I would recommend seeing a hearing specialist;):-D

[XfireZ51]

Forgot about this video. Its more along the lines of mike100s video w a better
audio track I think.

http://i187.photobucket.com/albums/x198/Z51Xfire/ROZA%20NERO/th_C6EBA4A0-CEBC-4F2A-968E-5A1A08B79808_zpsp2t5gnbi.mp4 (http://i187.photobucket.com/albums/x198/Z51Xfire/ROZA%20NERO/C6EBA4A0-CEBC-4F2A-968E-5A1A08B79808_zpsp2t5gnbi.mp4)

[Schrade]

Anyone ever open the PE mufflers?

One person has opened up the tips, that I know of here...

Open:

https://lh4.googleusercontent.com/-qo058ZFDlZk/U_fNX35RauI/AAAAAAAAEv0/WsmouOV5w5U/s768/IMG_6681.JPG

and closed:

https://lh4.googleusercontent.com/-_wOqTsLNmk4/U_fNt0DxzQI/AAAAAAAAEwA/csLzm9xGQYk/s768/IMG_6680.JPG

[edram454]

I finally modified my exhaust and now have long tube headers going to a 4 inch y pipe then out to two 2.5 inch duals exiting into 2 2-chamber flowmaster mufflers. I will tell you that removing those flowmaster resonators have given my car a tremendous performance seat of the pants feel. It is felt very hard after 4k rpm's. It almost feels like it wants to break the tires loose. The sound is tremendous!!! All hell is breaking loose back there while in wot. I would love to be able to follow my car as someone floored it. There is serious drone at 2k rpms. It is bad but I dont care. The car makes a statement even at idle. Being a black menacing car and now with that sound and after tearing off my window films so you can see my roll bar inside, it looks like a very serious Corvette not to be messed with. This is just what the Doctor ordered. It will stay this way.

[edram454]

by the way, those resonators weigh a ton. With the removal of the large 3 chamber mufflers, spare tire carrier and tire and now the super heavy resonators my car feels much lighter. It feels like I can roast the tires any time I want. It is good to lose weight.

[XfireZ51]

A Y-pipe???

[edram454]

yes the y pipe goes where the headers would dump into the flowmaster resonators, so in place of the resonators he placed a 4 inch y pipe where the exhaust combines much like an h pipe or an x pipe and then it comes out into 2 2.5 inch pipes. the 4 inch pipe flows like a mother. I just dont sense any restriction on this setup over what I took off. I can tell the car just wants to rev and go effortlessly. It fits very nicely in the middle in the exhaust tunnel perfectly. I would have thought he would have used an x pipe but he said this would flow if not the same better. After the headers, flowmaster had two 2.5 inch pipes going into one opening in the resonator. It is at that point where the 4 inch pipe is welded and it shoots out to 2 2.5 inch duals straight out.

Miami muffler is the biggest custom exhaust business in south florida and probably the whole state of florida. They do semi's, race cars. etc.. anything with exhaust. all types of grade steels and solid aluminum exhaust also. He sells to other exhaust companies since he has a several mandrel pipe benders. He also sells on the internet as vrs exhaust for all types of cars. I am pleasantly surprised at the outcome.

[Schrade]

I finally modified my exhaust and now have long tube headers going to a 4 inch y pipe then out to two 2.5 inch duals exiting into 2 2-chamber flowmaster mufflers. I will tell you that removing those flowmaster resonators have given my car a tremendous performance seat of the pants feel. It is felt very hard after 4k rpm's. It almost feels like it wants to break the tires loose. The sound is tremendous!!! All hell is breaking loose back there while in wot. I would love to be able to follow my car as someone floored it. There is serious drone at 2k rpms. It is bad but I dont care. The car makes a statement even at idle. Being a black menacing car and now with that sound and after tearing off my window films so you can see my roll bar inside, it looks like a very serious Corvette not to be messed with. This is just what the Doctor ordered. It will stay this way.

:blahblah: yeah yeah yeah - mine will be Black too pretty soon (with Black rims on the corners too, which EVERYone knows are faster), except mine will be even ... slower ... with the super heavy-duty 4L60e tranny fluid pump suckin' HP + TQ.

[Schrade]

Ok - this went right over my head before here http://www.theologyweb.com/campus/images/smilies/whoosh.gif (as does lots of stuff, but we won't go there too much...

But let's see if I got this right - if I open ONE side of my PE's, and leave closed the OTHER side, then I can reduce resonance???

https://lh4.googleusercontent.com/-qo058ZFDlZk/U_fNX35RauI/AAAAAAAAEv0/WsmouOV5w5U/s768/IMG_6681.JPG

THAT I CAN see, and with an X section near the front, I'm not creating an IMbalance in exhaust flow, between L + R banks???????????????????

If you don't care about drone, then find some PE's, like I got from Jeff. The SPL, in dB's, HAS TO be 3 figure range. Ironically, it doesn't seem very loud at all, listening as my neighbor drove off around the block, after the last bolts were tight. I think Jeff might still have the link posted to the boards here... (in a moment here)
Jeff does still have his video on 'Public' setting here... (http://s446.photobucket.com/user/2manyvettes24/media/Power%20Effects%20Exhaust/ZR-1PowerEffectsClosed_zps10cc28f4.mp4.html?sort=3&o=2)

I'd have guessed, NOT from experience, that this hardware has more drone than any other aftermarket pipes. And now it seems that Bob WT has qualified that guess.

If mine wasn't running so much cooler, I think I'd have been looking for different hardware.


edit:
And I think mike100 said that drone could probably be reduced with a single outlet open, as opposed to both outlets, each side.

I can't see that reducing drone, but he knows more than me, so I won't argue.

[edram454]

:blahblah: yeah yeah yeah - mine will be Black too pretty soon (with Black rims on the corners too, which EVERYone knows are faster), except mine will be even ... slower ... with the super heavy-duty 4L60e tranny fluid pump suckin' HP + TQ.

At least you wont miss a shift! You must be a heavy duty drag racer if you are installing a auto trans in your z. there was a while there where the big time engineers were putting auto transmissions in race cars. I remember a couple of Jim Halls Chaparrals had them and also zora duntov put a auto trans in the cerv 2 prototype car with 4 wheel drive and two torque converters. I believe that car was at the Corvettes at Carlisle this year. It was donated to a museum by GM but the museum later sold them. Zora was pissed and so was GM.

I am sure your z will run just fine with one. Make sure you have a high stall.

[XfireZ51]

Why would you not replace the resonator w an X pipe?

[edram454]

The owner of the exhaust shop said that a y pipe with the dimensions that he had with a 4 inch inlet and out with 2 2.5 inch pipes would be a cleaner install, would allow me to use what pipes I had of my system and going back to the original flowmaster would be a snap if I ever wanted. The way the flowmaster system was designed it had the pipes that came off the header going into the resonator into one pipe. I looked inside the resonator and was surprised how restrictive it looked. It appeared to be two pipes since 2 pipes exited the resonator but it was only 1 pipe going in and it wasnt 4 inches either. I believe it was 2.5 inch inlet. the inside of the resonsator had the left side going off and through the resonsator while the right side went off to another smaller pipe which just bounced the waves around to reduce drone which was the job of the resonator anyway but it lacked any direct outlet into the exiting 2.5 inch pipes.

the proof was in the pudding when I drove the car right after I had driven it with the resonator in place and it was night and day. I still can believe the difference. It works kind of like an x pipe since both pipes exit the header, meet at a 4 inch pipe junction and exits out in 2 2.5 inch pipes. I remember in my drag racing days that one large pipe can out flow two small pipes, for example 1 3 inch pipe outflows 2 2 inch pipes. I knew that the 4 inch junction would not be problem what so ever. It is unconventional but makes sense as far as flow and cost. The cost to modifiy this was much less than an x pipe that would go from the headers to the mufflers and I can return it to the flowmaster force 2 configuration by welding it back together if I wanted to.

The idle noise is noticeable and people will notice. the wot is as loud or louder than a corsa with long tube headers and no cats. also the system weights less since there is less pipe. I think it was clever on the part of the shop owner and he's done many thousands of custom systems in his 30 years of business. I believe I was a little lucky to achieve the sound I was after for such little money and with the flexibility of bringing it back to how it was along with the weight savings.

ed ramos #3028