Let's talk exhaust and Prochargers.
#1
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My current setup is a D1SC, 4.00" blower pulley, ATI 7.65" crank pulley, FMIC, 3" charge pipe to the throttle body. FAST 90mm intake, PI (MAST) heads, QTP original style long tubes, 1 3/4", Kooks 3" ORY, Magnaflow catback. Right now I'm seeing ~195kpa at 6800rpm, and was wondering how much of a gain in power, and drop in boost pressure I'd see going with a set of 1 7/8 long tubes. I'm stock cubes, forged of course.
Ideally, I thought about going to the 1 7/8" longtubes, 3" ory, and then a 3.5" or 4" intermediate pipe. But I've heard debates saying that as the exhaust moves away from the motor and starts to cool, you need less exhaust volume to keep the velocity up.
If I go with the larger long tubes, I'm going to have them ceramic coated to keep the temps in the headers and the velocity up.
So is it worth it?
Ideally, I thought about going to the 1 7/8" longtubes, 3" ory, and then a 3.5" or 4" intermediate pipe. But I've heard debates saying that as the exhaust moves away from the motor and starts to cool, you need less exhaust volume to keep the velocity up.
If I go with the larger long tubes, I'm going to have them ceramic coated to keep the temps in the headers and the velocity up.
So is it worth it?
#2
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I have a similar setup but have 1 3/4 going into a custom true dual setup. I have asked this question to myself several times is it worth changing. I'm really interested in hearing feedback.
How much power are you putting down?
How much power are you putting down?
#3
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I am going with kooks 1 7/8" headers, 3" y and a mufflex 4" with a magnaflow muffler. I think going with larger headers will net you a decent gain. I am making that assumption based on what people gain when switching to larger headers on na setups. Combine that with a 4" intermediate pipe and you should pick up quite a bit.
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#12
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You'll probably see a gain on the dyno after tuning, you MAY see a gain at the track... I doubt you'll notice anything in the seat of the pants.... So if you're never gonna dyno the car to see where its at, and not going to run it at the track to benchmark it, I think you're wasting your money.... If anything, get rid of the single 3" Y pipe and go 3" duals... I'd do that for sure, regardless whether I changed headers.
1 3/4" headers on a 346@6800 is plenty, especially at only 14 psi of boost.. I mean you MAY gain 5-10rwhp but...i'd be surprised..
We just made 815rwhp on a buddy's C6 with 1 3/4" Breathless headers and 3" pipes (duals ofcourse). That was with a D1SC, 4" pulley and 8" balancer. 15 psi on a 402".
A pulley swap and a meth kit would net you WAY more gains and more seat of the pants gain for sure...and way cheaper.
***NOTE***
This is coming from someone with 2" ARH...
1 3/4" headers on a 346@6800 is plenty, especially at only 14 psi of boost.. I mean you MAY gain 5-10rwhp but...i'd be surprised..
We just made 815rwhp on a buddy's C6 with 1 3/4" Breathless headers and 3" pipes (duals ofcourse). That was with a D1SC, 4" pulley and 8" balancer. 15 psi on a 402".
A pulley swap and a meth kit would net you WAY more gains and more seat of the pants gain for sure...and way cheaper.
***NOTE***
This is coming from someone with 2" ARH...
#13
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You'll probably see a gain on the dyno after tuning, you MAY see a gain at the track... I doubt you'll notice anything in the seat of the pants.... So if you're never gonna dyno the car to see where its at, and not going to run it at the track to benchmark it, I think you're wasting your money.... If anything, get rid of the single 3" Y pipe and go 3" duals... I'd do that for sure, regardless whether I changed headers.
1 3/4" headers on a 346@6800 is plenty, especially at only 14 psi of boost.. I mean you MAY gain 5-10rwhp but...i'd be surprised..
We just made 815rwhp on a buddy's C6 with 1 3/4" Breathless headers and 3" pipes (duals ofcourse). That was with a D1SC, 4" pulley and 8" balancer. 15 psi on a 402".
A pulley swap and a meth kit would net you WAY more gains and more seat of the pants gain for sure...and way cheaper.
***NOTE***
This is coming from someone with 2" ARH...
1 3/4" headers on a 346@6800 is plenty, especially at only 14 psi of boost.. I mean you MAY gain 5-10rwhp but...i'd be surprised..
We just made 815rwhp on a buddy's C6 with 1 3/4" Breathless headers and 3" pipes (duals ofcourse). That was with a D1SC, 4" pulley and 8" balancer. 15 psi on a 402".
A pulley swap and a meth kit would net you WAY more gains and more seat of the pants gain for sure...and way cheaper.
***NOTE***
This is coming from someone with 2" ARH...
#14
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I think you would notice a gain once you go to a 3.40 pulley, but I doubt you would feel a difference at your current boost level. Bob
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I'm new to the FI realm, and I may be thinking too general or old school on this, but isn't it always beneficial to "cross over" your exhaust flows at some point instead of coming straight out the headers and out?
I understand the whole aspect of the path of least resistance, but I've always heard a crossover, or Y pipe uses the Venturi principal advantageously to use flow to "pull" away exhaust gasses from the opposite bank.
Just curious how that plays in here?
I understand the whole aspect of the path of least resistance, but I've always heard a crossover, or Y pipe uses the Venturi principal advantageously to use flow to "pull" away exhaust gasses from the opposite bank.
Just curious how that plays in here?
#18
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I started to change my exhaust over. Just picked up a used 4inch mufflex and waiting to find a deal on some 1 7/8s headers. anything has to make more power then the crappy pacesetters and ypipe that's on the car now. I thought I read awhile ago that a supercharged car doesn't require a lot of back pressure, that you want as free flowing as possible.
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I started to change my exhaust over. Just picked up a used 4inch mufflex and waiting to find a deal on some 1 7/8s headers. anything has to make more power then the crappy pacesetters and ypipe that's on the car now. I thought I read awhile ago that a supercharged car doesn't require a lot of back pressure, that you want as free flowing as possible.
You're gonna think I'm a liar, but about a year ago, I bought the 1-7/8" version of these headers for my 2000 SS off of Amazon for $399
![Amazon.com: BBK 16940 1-3/4" Silver Ceramic Coated Full Length Header for GM LS-1 F-Body: Automotive](https://ls1tech.com/forums/images/misc/amazon_icon.gif)
Seems the price has went up - BIGTIME! But, I'll attest to their quality and fit. They look and work great! Sound awesome, too!
Might keep your eyes peeled on Amazon to see if they run a good deal like the one I got.
And, I thought I'd also mention...I'm usually not a fan of white cars, but yours look freakin' amazing! Awesome ride!
#20
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FWIW I see 180 kpa with a 4.25 blower pulley at 6500 rpm. stock motor/heads with a cam. 1 7/8" TSP longtubes and TSP true duals. Car made 638/538 on a dynojet and traps 102-103 in the 1/8th