Exhaust gurus step inside
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,699
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From: The Black Hole LA
Exhaust gurus step inside
I was just wondering what is the best set up for an L98. Currently I run true duals 2.5" with only precats and no name performance mufflers. Is this system better or worse than say a cat-back system? I know that the lt1 needs that back pressure, but not sure on the L98. I was also thinking about putting an X-pipe on right behind the tranny, is it worth the time? And if I go to headers should I do away with the precats? If anyone has some actual dyno numbers on different setups I would really like to see them. Thanks.
Team Owner
Joined: Sep 2001
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From: Athens AL
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Re: Exhaust gurus step inside (hz900)
The best setup would be full longtube headers, either 1 5/8" or 1 3/4" depending on the HP you are making from the motor. Either should give about 15hp on the L98 over the manifolds and the precats. LT headers delete the precats (hooker, Tpis, LPE ceramic coated are all popular brands)
If your exhaust catback is some cheapo one, it may or may not be a help over the stock catback, i dont know. Most of the popular catbacks give 10hp over stock, but i dont know about yours. (flowmaster, Borla, B&B, Power Effects)
If your exhaust catback is some cheapo one, it may or may not be a help over the stock catback, i dont know. Most of the popular catbacks give 10hp over stock, but i dont know about yours. (flowmaster, Borla, B&B, Power Effects)
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,699
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From: The Black Hole LA
Re: Exhaust gurus step inside (ncider)
Don't know about the back pressure thing for sure, just what I've heard, and read here a few times.
Yeah live in Ruston, did not know anyone on here was from Ruston too. Shoot me an email, maybe we can grab a beer some time.
Yeah live in Ruston, did not know anyone on here was from Ruston too. Shoot me an email, maybe we can grab a beer some time.
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From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
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Re: Exhaust gurus step inside (hz900)
I'm a firm believer that on a stock LT1 you need the backpressure. This is based on my own results in my car.
Le Mans Master
Joined: Oct 2001
Posts: 5,302
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From: Atlanta GA
Re: Exhaust gurus step inside (hz900)
Where did you get your true duals from? Are they the ones out of Mid America, or did you have a muffler shop make them for you? If they are custom made, how much did they charge you and what type of pipe did they use (stainless, alum. steel, etc). Thanks.
Oh yeah, I've been to Ruston a few times myself. :seeya
Oh yeah, I've been to Ruston a few times myself. :seeya
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,699
Likes: 2
From: The Black Hole LA
Re: Exhaust gurus step inside (dtorc4)
Got a real good deal on the pipes. Muffler shop back home where my parents live charged me $100 "cash" for the pipes and labor and I already had two mufflers and tips so they put those on at no extra. They are not mandrel bent though. They are steel, but not stainless unfortunately. I have had the car for 5 years and only replaced them once, only this time at a different shop where I live now for $150 for same thing. The only problem I have had is that I have broken a number of hangers due to the weight. I just had them redone about 6 months ago and have been meaning to see if I can put another hanger somewhere.
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From: Hillsboro OR
Re: Exhaust gurus step inside (hz900)
No exhaust system needs back pressure. What you do need is a system that is sized so it keeps exhaust velocity up to keep the exhuast moving and has smooth curves.
Get rid of the precats since you don't have the cats anymore. Put the X crossover after the trans. It will reduce the exhuast noise, and improve lowend performance. The best exhuast system has smooth mandrel formed bends with no sharp kinks. A set of good flowing mufflers is desireable but it becomes a trade off between flow and noise at some point.
Get rid of the precats since you don't have the cats anymore. Put the X crossover after the trans. It will reduce the exhuast noise, and improve lowend performance. The best exhuast system has smooth mandrel formed bends with no sharp kinks. A set of good flowing mufflers is desireable but it becomes a trade off between flow and noise at some point.
Racer
Joined: Jan 2002
Posts: 322
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From: ruston la
Re: Exhaust gurus step inside (AquaMetallic94LT1)
No exhaust system needs back pressure. What you do need is a system that is sized so it keeps exhaust velocity up to keep the exhuast moving and has smooth curves.