Re: exhaust
 

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.

Re: exhaust
 

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?

Re: exhaust
 

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...pictureid=2641

http://www.zr1.net/forum/picture.php...pictureid=2642


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

Re: exhaust
 

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?"

Re: exhaust
 

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

Re: exhaust
 

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.

Re: exhaust
 

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

Re: exhaust
 

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!

Re: exhaust
 

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.

Re: exhaust
 

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