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Old 01-25-2007, 03:54 AM   #11
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Quote:
Originally Posted by corvettecrazy
only reason for a 3inch DP on a L36 is if there is a turbo sitting between the downpipe and motor because at that point the back pressure doesn't matter much
Or if theres some weird looking metal thing with a pulley sitting on top of or near the engine.
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Old 01-25-2007, 03:57 AM   #12
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Quote:
Originally Posted by 95naSTA
Quote:
Originally Posted by corvettecrazy
only reason for a 3inch DP on a L36 is if there is a turbo sitting between the downpipe and motor because at that point the back pressure doesn't matter much
Or if theres some weird looking metal thing with a pulley sitting on top of or near the engine.
then it likely wouldn't be a L36 :P
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Old 01-25-2007, 04:08 AM   #13
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True It wouldn't fully be with the heads and stuff on there unless its csc'ed.
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Old 01-25-2007, 08:28 AM   #14
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Mike, I changed my DP to a 3" before the headers. I noticed a decrease in low end. No doubt. It takes a lot to outflow your stock 2.0? downpipe. I say 2.0? because the inner diameter is closer to 2.0" than 2.5". I haven't precisely measured though.

The difference from what we call a 2.5 DP to a 3.0 DP is really nearly a full inch.
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Old 01-27-2007, 05:22 PM   #15
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I'd say stock is about 2.25" if you account for the sleeve.
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Old 01-28-2007, 03:37 AM   #16
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I think a built L36 should have long tube headers with small primaries and 2.5" exhaust the rest of the way back. That would be the ultimate exhaust setup on my car.
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Old 01-28-2007, 04:28 AM   #17
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I played around with formulas, a couple calculators, and contacted a local gn shop about pricing and dimensions. For a higher reving L36 you would want the primaries to be about 30-33" with a 1.5" diameter. Since my headers were destroyed, I am going to make a set like this.
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Old 01-28-2007, 04:33 AM   #18
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Mike, that would kick a serious amount of @ss. Boy, I wish I could do a set of headers right now! I hope you can do all the cool stuff you're planning on your next 3800 build.
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