ok, i know theres a lot of exhuast threads on here, but so far they all seem to be about types, not pipe sizing, so here we go, i have a mostly stock ls in a crx, i have an ES Oval for it, but i need suggestions on custom pipe sizes, im not goin boost any time soon, and i want it fairly quite, i think im lookin at 2.25 with a res, but not sure, any advice is helpfull, thanks guys!

 

just bolt the muffler onto your stock tubing. When you boost, depending on your boost level, the optimum size is 2.5-3" 60-70mm

 

no stock exhaust with an ls swap is a power killer

sounds like you got yourself made already though, 2.25 is what I went with after researching because you still keep your low end torque and still get the h/p number in the high rpms (compared to 2.5)

If you want all top end go 2.5, more torque but not as much top end 2.25

Resonator always helps though

 

Dumb question, but does the resonater replace the cat and is it smog legal for my yearly check?

 

resonator does NOT replace the cat, just add it in between the cat and the muffler somewhere.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crx_88_si &raquo;</TD></TR><TR><TD CLASS="quote">resonator does NOT replace the cat,</TD></TR></TABLE>

Looks can be deceving

 

ok, i guess its cutsom 2.25, next thing is the cat.... cuz i know stock cats arent that size, what is recomended, and are they (what ever they are) easy to find, pretty much basic info btw thanks for all feed back

 

i used my stock cat, I even went to the junkyard and grabbed another stocker that was all plugged and rammed a bar through it and got rid of all that mesh, I use that cat on weekends and for races

 

sounds good, big sound difference between the stocker and the punched out stocker? and, please excuse my retardation, but when i go to the piping shop to get my exhaust done, what should i tell him about the cat??

 

crush bent tubing from the muffler shop is as bad as the stocker.....

 

i know a guy that does manderel bent

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StealthEF &raquo;</TD></TR><TR><TD CLASS="quote">i , I even went to the junkyard and grabbed another stocker that was all plugged and rammed a bar through it and got rid of all that mesh, I use that cat on weekends and for races</TD></TR></TABLE>

This is making your loose power. Exhaust gases swirl up inside and actually restrict flow more then a stock cat.

The PROPER way to do it if you want the 'look' of a cat but no restriction is to find one of the cats with the bolts in each corner that hold it together.

1)Take apart the cat
2)Take the stuff out
3)Get a piece of straight exhaust pipe that just fits in the opening of the cat
4)Cut it to lenght and weld it inside
5)Close the cat back up
6)Bolt onto veichle

-Enjoy

 

i think that would loose sight of the quiet part of my exhuast, i dont want something that attracts the law from a 1/2 mile from my car, so.... on that note i think i may try to find some way to tone it down... any after market cats for 2.25 piping that keeps things quiet?

 

So i can use my stock exhausat with my b18b swap....sorry if its a lil off topic

 

Just go buy a 2.25" cat from Checker... They've got to look it up in thier catalog by size, not by application. They're like $80. I had a 2.5" for my old system and I picked up a 3" ID Cat for my new system (3" mandrel bent from Dr. Gas... )

 

If you are worried about it being too loud, then just get a larger resonator.

 

would you consider there to be too much back pressure with a 2"?
i ahve a B16a in my EF and i'm keeping the stock exhaust manifold and downpipe.. so is it worth getting 2.25"?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by v8hunter03 &raquo;</TD></TR><TR><TD CLASS="quote">would you consider there to be too much back pressure with a 2"?
i ahve a B16a in my EF and i'm keeping the stock exhaust manifold and downpipe.. so is it worth getting 2.25"?
</TD></TR></TABLE>

Its usually smart to keep the same size as your header/downpipe flange, if you plan on upgrading to a header with a 2.25 or 2.5 flange, then change the pipe.