alrite on my 95 ex i am redoing all the exhaust and im wondering if i should go high flw cat since im doing header and cat back. now ive herd that cars w/out F/I run better with back pressure or sumthing. i am getting Greddy SP2 and it has a muffler on it, unlike the RS*R Exmag GT-II i used to have on my teg. i loved that exhaust. but n e wayz, the SP2 has a muffler unlike the straight through design of the GT-II. so if it alredy has a muffler, would a high flow cat benefit me or should i leave it for more back pressure? or is this whole thing i herd about back pressure not even true? o yea my friend who has a 1.8T said to me the other day when i told him i wanted a high flow cat "you no you actualy lose power with a high flow cat becuase of back pressure". so that brings me here with this question: high flow or stock?

p.s. is it the same to just gut a cat instead of buying a high flow one?

 

The higher flow will hurt on the low end if any or at all but will cancel out any power loss on the top end. Which means you will gain overall power.

 

I have a high flow cat on my b18c hatch with a full 2.25 inch exhaust system, and I notice more gain in top end than loss in low end. And actually my high flow was cheaper than an O.E. replacement, so I thought WTF? Right?? I am happy with it, I would go with high flow.

 

If you are looking for good prices for a high flow cat check this site out
http://www.performancepeddler.com/default.asp

 

High flow cats try to remain emissions legal (at least they should by law if they're for legal street use), and just have a much larger catilyst grid inside. Gutting a cat typically consists of cutting a big hole in the grid, which allows the gases to avoid going though the catilyst. Basicly, a legal high flow cat removes bad ****, and a gutted cat does jack **** for emissions.

 

If your in an area where they don't do emissions testing i'd just go with a test pipe. Your friends comment about needing backpressure in only half-true. What you ideally want is low backpressure but high exhaust velocity. Make sure your "high-flow" cat is not just a gutted design becuase that will cause a loss of HP.

 

I would go with a test pipe.I have a 94 ex when i put the test pipe it made a diff.
in top end. Con- made it a little louder

 

the cost of gaining 1-5 hp isnt worth killing our environment. just stick with the OEM cat.

 

im gonna run a test pipe at the track, but for daily use it's too loud and i smell like unburned exhuast every time i drive.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Iceman05 &raquo;</TD></TR><TR><TD CLASS="quote">im gonna run a test pipe at the track, but for daily use it's too loud and i smell like unburned exhuast every time i drive.</TD></TR></TABLE>

thats the way to do it

 

I ran test pipe with Apexi N1 for over a year.. it sounds damn good, but sometimes just anoying.... for daily ride. I'd say a high flow cat

 

dont mean to thread jack but does a high flow cat or test pipe affect gas mileage?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EK-TSOHCV-TechRider &raquo;</TD></TR><TR><TD CLASS="quote">If you are looking for good prices for a high flow cat check this site out
http://www.performancepeddler.com/default.asp </TD></TR></TABLE>

Damn those ARE some good prices!

 

i have a stock header, cat back, and hi flow cat and it runs great.

the hi flow cat will make the exhaust louder and be less restrictive but i dont know how well it runs with a header attached too.

with hi flow or any other performance mods will affect gas mileage. varys per application. i lost about 5-8 mpg with hi flow cat and cat back

 

i have a test pipe and no muffler. so its just header and straight pipe all the way through the back. its really loud. especially on the freeway. its good on the top end and all right in low end. but i like it though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D21X &raquo;</TD></TR><TR><TD CLASS="quote">the cost of gaining 1-5 hp isnt worth killing our environment. just stick with the OEM cat. </TD></TR></TABLE>
amen.