...Guys this may or may not sound like a noob question, but I figured it cant hurt to ask right? Whats the worst that can happen? Oh, thats right ,I could get flamed viciously on HT...lol...

...Anyway...Im lookin into getting a new exhaust for my 95 hatch that has a b16 sir-ii...My options are a complete hks hi power catback (2.25 exactly, as stated on various websites) or a custom piping setup mated to a Apexi n1 n/a muffler tip (60mm)...I also plan on getting/running a test pipe to run w/ the exhaust, so ill be running a greddy 4-2-1 stainless steel header/test pipe(skunk2 or omni)/2.25' exhaust system...
...My question is, when Ive researched the test pipe size and fitment, they come in the options of 2.25 or 2.5', for the jdm and usdm sizing it says...fine, but ive read for both the skunk2 and omni test pipes that the 2.25' sizing is actually designed for 60mm exhaust systems , which as we know, is not technically 2.25, its like 2.36 or somethin...I believe 55mm is exactly 2.25...

...I currently am running an apex ws2 which is 60mm size piping...So would the test pipes (the 2.25' version) fit my 60mm ws2 fine, and have problems w/ the 2.25' 55mm hks hi power? or is the difference so minute that there will be no problem using them on the hks exhaust? ... I realize I may have made this sound more confusing then it really is, but it was kinda hard to relay exactly what im trying to say...can any1 help?...I want to make sure that there are absolutely zero fitment issues with anything...

 

get a cat.

 

...I appreciate the suggestion, but can I ask as to why you say that?...Any reasoning, for the cat, or against the test pipes?...

 

well, because the catalytic converter reduces pollution WAY more than it restricts power, and it sounds like it would solve your problem because the testpipe is the problem right?

 

...Well the testpipe isnt really a problem, not yet anyway, it will be if it wont fit my 2.25 55m piping yes, in which case I may go with a cat, but if it wont be a problem, and the test pipe will mate up to the rest of the exhaust fine, then ill be good, thats what im tryin to find out tho, I am still open to suggestions tho so keep them comin...thanks...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by professor poon &raquo;</TD></TR><TR><TD CLASS="quote">well, because the catalytic converter reduces pollution WAY more than it restricts power, and it sounds like it would solve your problem because the testpipe is the problem right?</TD></TR></TABLE>
didnt you ever see tractor trailers blowing out huge clouds of black smoke? hmmm isnt that considered pollution?


To the OP ive had that same question while ive been searching around the internet looking at test pipes.

 

Go with a 2.25" piping if you're N/A, no need at all to go bigger.

If you like the way your car sounds now, I wouldn't lose your cat. I thought it would be a good idea to use a test pipe, and now I almost can't wait to get my stock header and stock cat back on. The cat is the main resonating source in your N/A exhaust system, take it out, and your car sounds like **** with that "tin can" sound.

I even have the WS2.

 

I have the 2.25in skunk2 test pipe and it fit perfectly to the rest of my 2.25in exhaust so I would suggest just getting that one.

 

bump anybody else?...

 

bump anybody else?...and just for general suggestions...like I said i have the greddy 4-2-1 SS header now...Go Greddy Header/Omni test pipe/ Custom piping 2.25' to Apexi n1 slanted...??.......Or Greddy Header/Omni Test Pipe/ 2.25' Hks Hi power Exhaust complete catback (gonna run about $100 more overall)...?...I know its my car my decision, and trust me, ill make my own, but Id like some opinions...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by cockerkid008 &raquo;</TD></TR><TR><TD CLASS="quote">
didnt you ever see tractor trailers blowing out huge clouds of black smoke? hmmm isnt that considered pollution?


To the OP ive had that same question while ive been searching around the internet looking at test pipes. </TD></TR></TABLE>

well despite the visible black smoke, diesel engines are cleaner and better for the environment. I'd much rather have some black soot in the air than a bunch of carbon monoxide... Plus your point is invalid because the government regulates pollution, and the "tractor trailers" aren't illegal due to pollution as a cat-less car is.

 

if you are gonna use a header with a 2.25" collector then get the 2.25" test pipe. if you are gonna be using a jdm type header with a true 2.5" collector then go with the 2.5" test pipe. the flange for the header connection is more important because it is a donut style gasket. the 2-bolt flange on the other end is probably the same on both pipes. a 1/4" isnt gonna matter with that kind of flange.

cliffs: get the omni test pipe that matches your header collector design.

 

Bump....thanks for the info guys...especially dpetro...its pretty much just what I need...but any other suggestions as to which route I should go?...

 

...Alright guys ive made my decision...Im going apexi n1 na muffler mated to custom 2.25' piping...question is now, i dont want to get just the piping itself, w/o a resonator or cat because ive heard a couple similar setups and theyre just too too loud, I want some volume to my car (and i know ill get it w/ the n1) but not unbearable...

....My question now is, guy down at the shop where Im probably getting it done at suggested I get a high flow cat to help limit the noise level slightly, and make it sound better overall...Im about to get a magnaflow stainess steel high flow cat...Question is, am I better off getting the actual high flow cat? or should I just get a resonator instead?...Will either one of them make the exhaust/piping sound better? or worse?...At the moment im goin w/ the high flow cat but I wanna make sure Im making the right decision...

 

bump any help?...

 

Save your money, use the stock cat. I was supercharged running a DCsports header, stock cat, and APEXi exhaust. When I switched over to a Kami and test pipe, I gained 4whp with a full 2.5" header + test pipe setup... that's it. You will be lucky if you see all of a 1whp gain.

Getting rid of the stock cat will not net you anything, so don't bother replacing it. The stocker will also keep your volume down to a bearable level.

Trust me, been there, done that, wasn't happy with the results.

 

...I feel you on the cat, and understand the explanation and appreciate it...

...Reason im lookin into the magnaflow stainless steel aftermarket cat is because I drive a lovely cx hatch...Light as she is, us CX owners were blessed with the d15b8 which incorporated the cat into the stock header, and not the actual exhaust piping...

...I doubt I wouldve been able to use that cat anyway since it was in the headers, but regardless I dont have it anymore since I got rid of the d15b8 when I got my b16 (shoulda kept that damn thing, just in case)...So I dont have a cat period...Figured Id get one to help lower the volume a bit when I get the N1 tho...

 

...Bump for more advice and suggestions...Hi Flow Cat or Resonator?...

 

...nothin else?...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by QualityMaterial &raquo;</TD></TR><TR><TD CLASS="quote">...Bump for more advice and suggestions...Hi Flow Cat or Resonator?...</TD></TR></TABLE>

BOTH

It will be good to your ears and sanity in the long run.