O.... M.... G....

[Paul Workman]

Originally Posted by rhipsher

That makes sense to me. My car is totally stock minus the borla. When I had it dyno'd at Coreys last month it ran 341.75rwhp 335.50 ft lbs torque. I asked Corey if that was normal for stock. And he said that was a little better than stock. They typically are around 325 for a 375 LT5. Weather those straight pipes that only cost me $30 bucks made a 16hp difference? I just don't know. But the resonator did have a much better sound than the straight pipes. But amazingly the straight pipes don't produce any drone at all which really supprises me.

Mine to is a stock 90 except for a Borla cat-back. Recently it dyno'ed at 339.x rwhp with the resonator, for what it's worth.

Speaking of Borla, w/ the resonator did you get a loud, narrow resonance up around 3300?

P.

[Pete]

Originally Posted by jonszr1

so what is petes setup ? i have a 21/2 in set up done by spin tec with a dr gas xpipe i picked up from the flowmaster set up i had , it went from 117.50 best mph to 119.85 best of each system . cars on u tube @ famoso. i wonder if using the factory 23/4 in tubing with 3 in turbo muffler with a 3 in x pipe might be the perfect size. just thought to share

Brad,i have Jeal headers,SW X-pipe, two 3" Dynomax bullits and Gen I B&B mufflers.
This is a full length 3" system.

Pete

[Aurora40]

Originally Posted by rhipsher

Weather those straight pipes that only cost me $30 bucks made a 16hp difference?

Well, it could have been any of the exhaust, not just the resonator replacement, right? But anything has got to be better than the 375hp exhaust system. If you look at the stock resonator, it is horrible. It necks down to less than 2" going into it.

[jonszr1]

pete thanx for the info. we have a private track day set for nov 22. i have a desert developement 3 in ,i will try to get a x pipe added to it and ssee if it will make a little more power . will try to have it set up so i can take both and change them between rounds and see how it works on my car .it may be though that i need your wonderfull ported heads to see an improvement . also am going to try some 18 in bfgs against the mt et street radials . will post the results on the 23 rd

[cward]

I doubt if I am the right person to comment on exhaust systems as noise level inside the Z was not a concern to me. Or to my most frequent passenger, Bob. I said BOB. Both of us are deaf so neither of us try to talk to each other when we are in either his Z or mine. This being the case, I went thru 4 iterations of exhaust combinations. Each was louder than the last. The final system was headers, X-pipe and straights in 3" SS. That last system was quite loud when you hit the go pedal. It also produced the highest hp. It also lowered my torque a few lbs. No back pressure moved my rpm range up several hundred rpm. My Z was over 390 rwhp 6000 to 7500. That is a long flat curve for hp which is one of the reasons my Z had some success against higher hp cars. When racing, I was in my power range nearly all the time. Finally, I'll get to the point, it is my opinion that an exhaust system is like BBQ: Everyone has their own idea of "best". Any system that can be driven on the street legally (straight pipes considered not legal ) is a compromise when compared to a non-legal straight pipe system. So go listen and ride in Z's with different systems and chose the one you like the most. I imagine that most of the aftermarket systems are all within a few hp of each other unless you have a stroker. So don't worry about a couple of hp and do what you want. If a few more hp is your only consideration, then a few of us ran my type of system on the street. But be warned, when you hit the go pedal, especially at 2 am, you can hear that exhaust for miles (and so can everyone else including the cops). A Cup car was not any louder than mine at full throttle.

Curtis

[cward]

I am sorry, I probably should not have commented on this thread. I was listening to some music: "Radar Love", "Hot Rod Lincoln" and the one my wife thought was most appropriate "Livin' on a Prayer". So I commented without much thought. I was in the mood.

Curtis

[rhipsher]

Originally Posted by jonszr1

did they put a crossover or x pipe in the system when they did it ? if not there is a few xtra hp in doing that

No cross over. They look like two side by side 2 1/2 ugly conduit pipes where the resonator use to be. The exhaust leaks were getting on my nerves so for $40 I took it to a muffler shop and had them weld up the leaks. As soon as I can I am going to get jeal headers and a B&B system with X pipe. And if I can't find any jeals I'll get something close. Then do the next most popular mod-port and polish plenun+injector housings. I'm the supervisor/CNC programmer/Machinist/Bosses whipping boy etc at the shop I am at. So I'd like to do my own porting and polishing. But first things first getting the exhaust squared away.

[Aurora40]

Originally Posted by cward

I am sorry, I probably should not have commented on this thread. I was listening to some music: "Radar Love", "Hot Rod Lincoln" and the one my wife thought was most appropriate "Livin' on a Prayer". So I commented without much thought. I was in the mood.

Curtis

I'm glad you did, and you make some good points!

I just wanted to provide my opinion of the Corsa, and how it differed from what I had previously. Certainly there are different strokes for different folks though!

Originally Posted by rhipsher

Since we are on the subject of exhaust I have a question that I have still not had a good answere for. I have a Borla system. And almost a year ago late one night I went over some railraod tracks and could kiss my resonater goodbye. You want to talk about drone! My Z sounded like a Southern Pacific frieght train comming down the road. So I measured the lenth of the res and went to midas and had them cut me two 2 1/2 inch pipes and flared one end just as a temporarely fix until I get another resonator. So my question is does running straight pipes instead of a resonator make for better breathability?

What you will find is the Borla resonator necks down to a 2.5 on the inside. Not exactly great. Adding straight pipes to the system will definitely help the flow, but you will pick up some horrible harmonics with the straight pipes.

[-=Jeff=-]

Originally Posted by Jeffvette

What you will find is the Borla resonator necks down to a 2.5 on the inside. Not exactly great. Adding straight pipes to the system will definitely help the flow, but you will pick up some horrible harmonics with the straight pipes.

Actually more like 2.25 or smaller and that is on the Challenge system as well