this muffler shop said that 2.5 for NA is too big for an integra and that i will lose torq. he said to stick with 2.25inches. is this true? he said that if i am running nos, turbo or supercharger, than a 2.5 or 3inch will be good.

ok here comes the editted post:
i already have short ram intake. i want to get header with 2.5 inch collector, change the cat and exhaust system to 2.5 inch mandrel bent. i want to gain top end power ( so gain at after 5k to redline), i do not mind sacrificing low end torq. future mods MIGHT be skunk2 stage 2 cams and a VAFC, or nos lol.

coming mods: light weight flywheel, lsd, brake lines, ATE super blue, engine damper or engine mount insert.

mods already: just suspension with a subtle drop.

u guys can tell i m trying to my car for the track. other than the NOS which is just for kicks


Modified by tekstyle at 4:49 AM 5/16/2004

 

depends on the state of your build

bigger piping will support more power, but if the header on your collector is only 2.25 inches, it won't make much difference if you have a 2.5 inch exhaust anyway

also by your muffler shops logic the JDM type R header would loose power, when it in fact provides a gain over the USDM type R header

just a couple of thoughts

 

most muffler shops will think 2.5 is is too big for an integra. they also believe backpressure is needed in a car which is not true car loses hp from too big of a system due to exhaust velocity being too slow. what your goals for the car built all motor 180-190whp+ id stick with 2.5. what header are u using?

 

thanks guys... i was planning on 2.5 anyways but i just wanted to make sure he was talking straight from his *** or actually using some brains when i was chatting with him.

 

it depends on what you are planing to do for the future. If you are going to keep your car stock, and only want a exhaust system for the sound, then 2.5" will only cost you more, and make you lose power. If you are going i/h/e, a 2.5" catback won't help you much either, because the cat is a bottle neck. If you go the FI route, or get bigger cams and a racing cat or test pipe, get the 2.5" or bigger.

 

Well, I can see why muffler shops would recommend going 2.5inch because unless you have a extreme NA setup, 2.5 will not be beneficial. Some guy even told me 3inch was too big for my turbo setup

 

2.25" -


2.5" -


same car, same setup, same ambient temperature, same dyno... fairly similar result

 

2.5" isn't going to gain you much power for a stock GSR over a 2.36" cat-back.


Modified by Calsonic180 at 5:07 PM 5/16/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Calsonic180 &raquo;</TD></TR><TR><TD CLASS="quote">2.5" isn't going to gain you much power for a stock GSR.</TD></TR></TABLE>

Compared to?

I see your other post that you are going crush bent. You're going to have bottlenecks at the "crushes" which will decrease your performance. It might even put you at the level of a mandrel bent 2.25".

 

i editted the post.. i hope this helps a lil bit more and clear things up.

 

Anybody who doesnt know about import performance will tell you that 2.5" exhaust is too big for a honda. The guys at the domestic shop I went to today told me that BS when I asked for a 2.5" resonator.

 

I don't think crush bending the piping is going to hinder the performance. At the local exhuast shop here said that if your not putting high horsepower over 200 getting crush bent piping isnt going to hurt you. once your reaching High horsepower, getting mandrel bend piping is some what beneficial. I'm sure im not totaly right on this but this is what i heard. Correct me if im wrong. so I can learn the real truth.

 

What is the stock piping?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by grn4drgsr &raquo;</TD></TR><TR><TD CLASS="quote">I don't think crush bending the piping is going to hinder the performance. At the local exhuast shop here said that if your not putting high horsepower over 200 getting crush bent piping isnt going to hurt you. once your reaching High horsepower, getting mandrel bend piping is some what beneficial. I'm sure im not totaly right on this but this is what i heard. Correct me if im wrong. so I can learn the real truth.</TD></TR></TABLE>

mandrel bent piping is getting what you're paying for, piping the diameter of the PIPE

crush bent pipe, reduces the ID of the pipe, as long as you take that into account get whatever you want

but it depends on other factors, like your header and collector

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96dc2 &raquo;</TD></TR><TR><TD CLASS="quote">

Compared to?

I see your other post that you are going crush bent. You're going to have bottlenecks at the "crushes" which will decrease your performance. It might even put you at the level of a mandrel bent 2.25".</TD></TR></TABLE>

I agree!
I had 2.5' at first and then I switched to a catback exhaust system.

 

shoot now that you made things clear. Go with 2.5" mandrel bends, to either a chambered or stright through muffle.

 

I would check this site out
Kteller.com
Id get piping from them. 2.25' if you go through them. make sure to pick up some resonators and then grab maybe a magnaflow muffler or es oval
if you have a shop crush bend it; i would go with 2.5'

 

when i went to the muffler shop they told me 2.5" was too big but i demanded thats what i wanted,turns out he only had 2.25" piping. thats y he said 2.5" was too big. my civic before the turbo had 2.5" with the stock 1.5 motor with i/h and after the piping was done i dint feel no low end loss in power. everythign in low end felt the same but mid/high def improve. and if this is on a little gas saving monster motor then it ll def be ok for the gsr.

 

if you want top end in your n/a beast, definately go w/ 2.5"

if you are like most people you will keep building your engine bit by bit and you dont want to have to get a new exhaust to accomidate the more power you will be making.

2.5" gets my vote for high end n/a, 2.25" for a daily streeter who doesn't care about top end, and 3" for boost no matter what

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RedStarGsr &raquo;</TD></TR><TR><TD CLASS="quote">if you want top end in your n/a beast, definately go w/ 2.5"

if you are like most people you will keep building your engine bit by bit and you dont want to have to get a new exhaust to accomidate the more power you will be making.

2.5" gets my vote for high end n/a, 2.25" for a daily streeter who doesn't care about top end, and 3" for boost no matter what </TD></TR></TABLE>

exactly what i was thinking.. i think i'll go 2.5 after i get some headers, but until then, still saving up.. thanks redstar as well as everyone else.

 

i have 2.25 on my 91 rs if and it has headers and intake and its perfect i think if you are not going to upgrade yor engine any further than 2.5 is ok