Got Corsa?
 

This is NOT a thread about which exhaust is best, etc. but I do hope to learn more about Corsa exhaust systems.

A little background: I had Corsas on a stock 94 LT1 years ago and basically liked them a lot. My 90Z had Borlas on it when I bought it (also got the original stock system as well). Later I added SW headers and high flow cats and also picked up a stock LT4 system as well as a Corsa system for possible later use.

This past weekend I finally installed the Corsas without the cats (I need to shorten the Corsa front pipes and currently don't have access to an exhaust shop that can mod stainless). First impressions ... wow, these flow really well without any resonance and boy, are they really loud at WOT. Normal driving, louder than stock and maybe even louder than the Borlas but certainly not too loud, but when I hammered it, the loudness was incredible and not at all what I anticipated. I'm not saying I disliked it, but surprised at the outcome.

So here's the question to those of you with Corsa experience ... will adding the cats tone down or "tame" down the overall loudness somewhat? I suppose that I was a bit surprised that Corsas on the LT5 w/headers was louder than I anticipated, especially since I remembered a "quieter" sound on the LT1 (no headers).

And has anyone heard a stock system (late LT5 or LT4) on a Z with headers and cats? I'm assuming that it would be fairly quiet with no resonance, but would it be "too quiet"?

Is anyone with either headers/cats/Corsa or headers/cats/stock going to be at BG with their Z? I really would like to hear these setups in person, possibly even a ride.

Thanks for reading and even more, thanks for the responses that I hope I get in this thread. I'm fairly certain that I will either stay with the Corsas or possibly try fabbing the LT4 stock system up ... no resonance and quiet (but not too quiet) are my goals.

George Jones

Re: Got Corsa?
 

Are you using a stock corsa resonator? Or an X pipe?

Re: Got Corsa?
 

Im using a Corsa system with Hi-Flow stainless RT cats, Jeal Headers and the standard Corsa resonator. Im guessing you are not

Re: Got Corsa?
 

I had the regular corsa setup on stock manifolds with cats- everything normal, and I thought they were too loud. Loud outside, little drone inside. So loud I got pulled over already going full throttle on the last block to the freeway entrance in town. I honestly believe it was the incredible loudness that got me popped, not doing 70 mph onto the on-ramp.

I went back to oem 2.7" pipes with an x-pipe instead of the resonator. I'm using 90 stock mufflers with the twin square tips at the moment, but may change mufflers in the future. it is really nice to be not loud again. it may be down a few hp over 5500 rpm- but it is hard to tell. The oem pipe is amazing as it doesn't resonate- no reason to throw away good engineering- if anything, its a bigger pipe size- kind of hard to argue against that.

Re: Got Corsa?
 

George,

If you're coming to BG, u can listen to mine although not a Corsa. I don't have cats but I do have an Xpipe. =Jeff= has a Corsa w cats I believe. Not sure they made much diff.
What mods to the motor?

Re: Got Corsa?
 

I have SW headers with Corsa resonator/mufflers. I used the SW ball flange adapter on the left side and the SW adapter pipe on the right side. The engine is stock except for intake & injector housing porting.

I have 3" high flow stainless cats that slip fit onto the headers and connect using v-clamp flanges on the exhaust side ... to install the cats with the above setup I need to have the Corsa front pipes shortened slightly and have v-clamp flanges welded on but I don't have access to an exhaust shop that will work with stainless ... so that's why I installed without cats.

No inspection in my part of Georgia and I know a lot of people who run without cats, but I actually prefer to have cats on my vehicles. I'm trying to make a decision on whether to go all the way back to the most free flowing stock system that I can find or go with the Corsa with cats. Today I'm leaning toward the Corsa ... who knows where I'll be tomorrow !!!

I am hoping to hear some good examples at BG in a couple of weeks or so.

Re: Got Corsa?
 

I'm writing my reply as a couple of replies got posted ... thanks, I'm getting some good, solid info. I imagine I'll be talking to several of you at BG as well as listening to your setups.

Re: Got Corsa?
 

There has to be something going on with your piping arrangment air leakage etc. Mine is quiet with no resonance and only gets louder when you hammer it. Not at all like the experience your talking about.

Re: Got Corsa?
 

Yes please stop by for some sausage and exhaust!

Re: Got Corsa?
 

Apologies if I mislead ... I have zero resonance (I tried to induce resonance in the 1500-1900 rpm range & could not) and it's reasonably quiet at idle/normal driving RPMs (altho not as quiet as the Borla). Driving normally with the windows up the sound is hardly noticeable. But at WOT it really wakes up & screams ... this is not necessarily a bad thing, but louder than I expected. I'm curious if adding the cats will tone the sound down any.

Re: Got Corsa?
 

now you're making me hungry ... anything I should bring besides an appetite?

Re: Got Corsa?
 

With 3 inch Hiflow stainless Random Techs or HiFlow 3 inch stainless Magnaflows. NO Thats what Im running now

With a more restrictive brand? Unknown. Sounds like everything is working normal. They bark when bit

Re: Got Corsa?
 

I don't think anybody will tell you Corsas aren't loud.

I have a clip of me speeding with the window down. You can hear the pipes echo off the brick wall 40 yards away toward the end of the clip- its kind of a stereophonic sound effect- just like it sounded in person when I made the clip (I think the statute of limitations apply- sorry about 30 miles north of the Mexican border so I'm not gonna use that disclaimer).

click this and tell me if you think this is mellow-

http://i29.photobucket.com/albums/c2...h_MOV02368.jpg

I took the Corsas off. You could travel on them (I went to AZ twice), but if you want to run hard on the streets, everybody will know about it.

Re: Got Corsa?
 

It will be more quiet with cats and you will lose a few ponies
I have SW headers, RT cats and corsa cat back, yes, it gets loud at WOT and fairly quiet when cruising with NO resonance
Like the rock documentary "It may get loud" with Jimmy Page

Re: Got Corsa?
 

hmmm ... I may have to change a couple of my habits when driving around town. I live in a small town where everyone knows everyone and a good bit is tolerated, but I'm not sure my habit of driving through town at high RPMs is going to fly.

Might have to drive up to the big city of Augusta and set off some car alarms in the parking garages (don't ask how I know that will happen) :wink:

Re: Got Corsa?
 

That is a definite concern

Re: Got Corsa?
 

Yep, that's the sound I'm getting. I guess my surprise was thinking that the sound would have been closer to the Corsas on my totally stock 94 LT1 ... I guess I wasn't really thinking. There's no way that Corsas on an LT5 with headers at WOT will ever be as quiet as Corsas on a stock LT1 that only dreams of revving that high.

Re: Got Corsa?
 

Sounds like mine. Whats not to love ;)

Re: Got Corsa?
 

I have stock manifold and cats with Corsa pipes and muffler.
What I like about it (and the neighbors) is that at idle and low rpm
it's tolerable. But when you're at WOT it opens up nicley.

Re: Got Corsa?
 

What are you running now?

Re: Got Corsa?
 

Quote:
Originally Posted by XfireZ51
Yes please stop by for some sausage and exhaust!


George,

Be careful what you ask for when talking sausage with those FBI guys, especially Pete and you being from the south....................Consider yourself warned. lol!

Re: Got Corsa?
 

Stock 2.7" pipes off of a 90, except the resonator has been replaced with an x-pipe. It is very quiet. Could be losing 10 hp on the top end though with stock mufflers- I will be testing it in the future, but it is really a pleasant change from the last year or so of only having loud exhaust on the car.

I may change the muffler at some point- that was always the plan. I wanted to have a pipe size in between 2.5 and 3". Certainly the oem muffler is quiet, but I also tend to think the odd stock pipe diameter, wall thickness, and bends lend itself to resonance control- no reason to completely throw out acoustic engineering that works.

Re: Got Corsa?
 

I did not sell them- they will bolt right back up if I need them again:p

Re: Got Corsa?
 

Headers or stock?
How quiet, both at normal RPMs and WOT?
No resonance at all?

I have 2 stock systems hanging in the garage ... the original OEM 90 that came with my Z plus a 96 LT4 stock system that was literally "given" to me. Even though our 90s came with the twin pipes each side I tend to prefer the later LT1/LT5 single tip so I'm curious about fabbing the LT4 system to the headers & cats. I'm hoping to find someone with this setup, especially if I could hear it.

Marc H. has a write up on his website with flow characteristics of several exhaust systems ... to summarize, the early LT5 stock exhaust cost about 20 HP, the later LT5 stock cost about 10 HP, Borlas also -10, Corsas & early B&B cost about -5. If I'm interpreting this correctly I can run Corsas and lose only about 5 HP or I can run the late stock (which should include the LT4) and have 5 HP less than the Corsa. At this point in my life (and what's left of my hearing after playing in loud bands for too many years) I'm leaning toward quieter and definitely no resonance, if any of this makes sense.

Re: Got Corsa?
 

If your motor is stock or top end ported, I would still recommend using the MagnaFlow cat back for LT-4. Overall I thought it was a very good system, good quality (albeit the hanger needs to be reinforced). It put out a great sound, very mellow, no drone and I was still able to put down 400rwhp thru it with headers. I alos liked the 4" rolled tips. Again apologies if I am hijacking the thread.

Re: Got Corsa?
 

I'm running stock manifolds with functional catalysts. It is stock quiet with just a small bit of rumble at full throttle due to the resonator-ectomy. It was silly quiet- I laughed when I started it up at the muffler shop. I could rev it up in the garage and still hear myself laughing.

If it can pull the same mph on my sooper secret test area, I will leave it, but most likely there is 5-10 hp being lost on the muffs. My longer term project is to get headers on it so I can realize more gains on my plenum/IH porting. The muffler seems to be a little less important than the stock manifolds at this point. I will change it later as needed.

The mid range punch seems pretty good despite going up in pipe diameter. For the money spent (not much) I'm having fun with it. On my car, the black twin square tips match my limo tinted windows and blackened tail lights (car is black too) for the complete Lord Vader type of look.

Re: Got Corsa?
 

Hey, it's OK ... when they come & visit me in Georgia I can always serve up possum on the half-shell ... and besides, I'm really from Texas, not far from the Mexico border.

Re: Got Corsa?
 

You will definitely enjoy the headers ... don't wait, get 'em soon.

Re: Got Corsa?
 

As a benchmark, I would tell you that my stock ZR trapped 111. Then came the headers w 3rd Gen B+B and it went 114. Porting the top end brought a
118.6mph best. That configuration dyno'd at 399+ rwhp.
The GVD ported heads and Pete intake cams w MFlow resonator and muffs
dyno'd 415. Replacing the Mflow resonator w SW Xpipe got the motor to ~430rwhp.
Haven't dyno'd the car with the re-porting of the top end and the
Dynomax Ultraflows + Z06 tips/flappers. That's up next. Right now I have a June 4th date w the dyno.

Re: Got Corsa?
 

Oh, I dunno.... Maybe it's that tinny ricer sound Corsa makes, no? :p

Real men love resonance!

JK! ;)


P.

Re: Got Corsa?
 

What? I can't hear you !!!