Should I use 2.5 or 3" exhaust?
01-22-2004, 01:45 PM
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Should I use 2.5 or 3" exhaust?
I was talking to my nearby muffler shop and the guy said I should go with 2.5 because of backpressure I was wondering what you guys think if I should go with that I have a 3" DP all opinions are highly appreciated!!! 
Set up:
d16z6(stock internal 9.2.1 comp)
t3/t4b
rev hard exh manifold and fmic
tial wg
greddy type S BOV will be changing to type R
3" DP
AVCR
all kind of guages
hondata
450cc inj
aem fpr
bbk fuel pump
Set up:
d16z6(stock internal 9.2.1 comp)
t3/t4b
rev hard exh manifold and fmic
tial wg
greddy type S BOV will be changing to type R
3" DP
AVCR
all kind of guages
hondata
450cc inj
aem fpr
bbk fuel pump
01-22-2004, 01:48 PM
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Re: Should I use 2.5 or 3" exhaust? (booscivic)
01-22-2004, 02:54 PM
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Re: (booscivic)
2 1/2, 3 would lose too much back pressure and affect low end on a sohc from what i have heard from other people who have already done it.
2 1/2 w/ N1 style muff, there are no flow issues.
im going to run 2 1/2 on mine.
2 1/2 w/ N1 style muff, there are no flow issues.
im going to run 2 1/2 on mine.
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01-22-2004, 03:07 PM
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Re: Should I use 2.5 or 3" exhaust? (booscivic)
why would u want 2 1/2inch piping when ur car should produce the most power open DP? So with that said i would keep it as free flowing as possable and get 3inch all the way back.
01-22-2004, 03:47 PM
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Re: (darkracer)
backpressure? on a FI'd car...nope...don't worry about backpressure it doesn't come into play.....it depends on how much lbs your boostin and how much noise you want to deal with
01-22-2004, 05:55 PM
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Re: Should I use 2.5 or 3" exhaust? (red cx)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by red cx »</TD></TR><TR><TD CLASS="quote">3" brother</TD></TR></TABLE>
01-22-2004, 07:30 PM
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Re: (RedTegLS)
There was a guy with a 1st gen DSM here and he ran a 11.70 with stock o2 housing and 2.5" it had stock cams even and ran 25 lbs that is why i see no use in running 3"
01-22-2004, 08:15 PM
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Re: (Rain_man)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">There was a guy with a 1st gen DSM here and he ran a 11.70 with stock o2 housing and 2.5" it had stock cams even and ran 25 lbs that is why i see no use in running 3"</TD></TR></TABLE>
huh???
what board are u on???
turbos don't need backpressure, N/A does..... go read!
**** DSM's!
mike
huh???
what board are u on???
turbos don't need backpressure, N/A does..... go read!
**** DSM's!
mike
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01-23-2004, 12:34 AM
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Re: (righteyeblind)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by righteyeblind »</TD></TR><TR><TD CLASS="quote">There was a guy with a 1st gen DSM here and he ran a 11.70 with stock o2 housing and 2.5" it had stock cams even and ran 25 lbs that is why i see no use in running 3"</TD></TR></TABLE>
i dont think anyones saying you can't run good times with a diameter smaller than 3", Everyones argument is that it's BETTER to run 3", quicker spools, more power, better times. and who knows, maybe that dsm guy could've ran an 11.20 or faster with a 3"? but we could sit here and speculate all nite..........
i dont think anyones saying you can't run good times with a diameter smaller than 3", Everyones argument is that it's BETTER to run 3", quicker spools, more power, better times. and who knows, maybe that dsm guy could've ran an 11.20 or faster with a 3"? but we could sit here and speculate all nite..........
01-23-2004, 04:23 AM
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SOHC plan
Why not get the best of both worlds.
2 1/2 dp
2 1/2 high flow cat
3" cat back
I figure this way, you save a little pressure so that tq doesn't go to hell, which probably would suck in daily driving.
2 1/2 dp
2 1/2 high flow cat
3" cat back
I figure this way, you save a little pressure so that tq doesn't go to hell, which probably would suck in daily driving.
01-23-2004, 04:46 AM
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Re: (b18b1hmtlove)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18b1hmtlove »</TD></TR><TR><TD CLASS="quote">3" crushbent.</TD></TR></TABLE>
I learned a long time ago.....dont post when you dont know jack! 2.5" mandrel bent would be better than 3" crushed
I learned a long time ago.....dont post when you dont know jack! 2.5" mandrel bent would be better than 3" crushed
01-23-2004, 07:33 AM
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Re: (RedTegLS)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RedTegLS »</TD></TR><TR><TD CLASS="quote">
I learned a long time ago.....dont post when you dont know jack! 2.5" mandrel bent would be better than 3" crushed </TD></TR></TABLE>
Dont assume based on my post count that i am unaware of what im talking about. a 3" crushbent exhaust at the bends is approx 2.5" ID, somtimes even larger depending on what type of pipe bender and who it is bending the exhaust. Also if DSM's can run 350whp or more on a 3" crushbent exhaust, i think he can run his little 200whp D series. If you have any assine comments you would like to share with the group, please dont refrain, i love to throw people misconception in their face.
I learned a long time ago.....dont post when you dont know jack! 2.5" mandrel bent would be better than 3" crushed </TD></TR></TABLE>
Dont assume based on my post count that i am unaware of what im talking about. a 3" crushbent exhaust at the bends is approx 2.5" ID, somtimes even larger depending on what type of pipe bender and who it is bending the exhaust. Also if DSM's can run 350whp or more on a 3" crushbent exhaust, i think he can run his little 200whp D series. If you have any assine comments you would like to share with the group, please dont refrain, i love to throw people misconception in their face.