Here is the deal, I am piecing together a turbo kit for my civic (jdm b16, t3/t4e). I have the option of spending a lot more money for a 3" downpipe and 3" exhaust, or just get a 2.5" downpipe and stick with my mandrel bent 2.5" exhaust.

I plan on making 260-280whpish if that helps.

So do you think the extra money for full 3" is worth it?

 

yes

 

yes it is, just get the setup from kteller, its like $200 for the full 3" piping in sainless.

 

I'd say stick with 2.5" for your power goals.

 

my 3 inch is quiter than my nasty farts.

 

If it were me and I already had a full 2.5" exhaust, I'd save my money and stick with it for that power level. The 3" may give a slightly better spool time, but I doubt it will be too noticeable. You could always get the 3" downpipe now to attach to your 2.5" exhaust and upgrade your current piping to 3" later on if you decide to run more boost.

 

If you have a 3" downpipe you will loose power by stepping it down to a 2.5" exhaust, i would go 3" , you will be better off

 

i would run 2.5 inch on a daily driver because its really quiet....but get an e cutout so when you up the boost for a race...you can run open 3 inch downpipe

 

For your power goals 2.5" is enough. You should be able to make 280whp with no sweat.

 

stick with what you got if its just gonna be stock motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hotimportcrx &raquo;</TD></TR><TR><TD CLASS="quote">i would run 2.5 inch on a daily driver because its really quiet....but get an e cutout so when you up the boost for a race...you can run open 3 inch downpipe</TD></TR></TABLE>

I vote 3" DP with 2.5" exhaust and a 3" cut out.

 

cut outs arent the most reliable things out there. I've went through a couple.

 

i have the same setup and i plan on using a cutout

 

me too. i have a 2.5 exhaust already and i'm getting an ecut out.

 

yup

 

i'm running full 3 inch.....i just got tired of having the downpipe dump down. its a whol lot quiter now....but you could always do a e-cut out.

 

say you were boosting a stock b16 with 2.5 DP to 2.5 Exhaust , how much power would you gain going to the 3in set up DP and exhaust....like hp? i'm trying to make about the same choice

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DBL &raquo;</TD></TR><TR><TD CLASS="quote">say you were boosting a stock b16 with 2.5 DP to 2.5 Exhaust , how much power would you gain going to the 3in set up DP and exhaust....like hp? i'm trying to make about the same choice</TD></TR></TABLE>

that all depends on other stuff, like size of turbo, what boost level, etc.

 

on my dyno at 14psi i made 360 on open down pipe andthen we bolted on my 2.5 hks hi-power i made 325 goes to show the difference