oversize exhaust

[tazman_tn]

this is my first post... 95 talon 420a n/t with only cai so far... i have tried doing a lot of research with no similar posts. here is my situation... everyone does 2-1/2" exhaust cat-back with good results, especially with a header. unfortunately i am unable to get a header. i am thinking about going 2-1/2 from manifold back. i work at a muffler shop, so it will basically be free other than time spent. i will be using a new flex section and resonator and 02 simulator and no cat so the entire system behind the manifold would be 2-1/2. i wanna hear opinions although i already know some people will say "no backpressure will hurt low end". thats ok ### its rev happy anyways.

 

[cs82685]

so what's your question? Sure you can do it, no you won't see much of a gain from it (if you say you can feel a difference afterwards, you're fooling yourself), also it'll probably sound like crap unless you throw in some resonators.

 

[rstare]

http://www.dsmtuners.com/forums/fre...8578-exhaust-straight-scoop-backpressure.html

 

[viperlp01]

That car isn't for speed anyways so if you can make it sound nice its a plus

 

[silver-2g]

i dont mean to sound dumb or anything because i simply do not know anything about these types of cars but....why cant you get a header?? do they just not make them for the 420a or what??

 

[PCD_RS]

i dont mean to sound dumb or anything because i simply do not know anything about these types of cars but....why cant you get a header?? do they just not make them for the 420a or what??

There are plenty of headers out there for the 420A motor.

2.5" should be good for the 420A application, also is good for a turbo set-up (although 3" is better). There is a power-gain but it won't be that much noticeable at all, honestly.

also it'll probably sound like crap unless you throw in some resonators.

I agree. I threw a resonator in the placement of my catalytic converter and it sounded like crap. So I put my cat back on.

 

[tazman_tn]

i guess i forgot to say that i cant get a header right now because of money situation..... my main thing was wanting opinions about going 2-1/2 all the way instead of just behind the cat

 

[silver-2g]

ohhhhhhh alright that makes perfect sense to me now i feel ya on that! i think you should go 2.5" and either like your cat in or totally delete it...i think that all high flow cats are crap because if you think about it isnt it just more free flowing and has a spot for your o2 sensor...cause on a test pipe you can have the o2 bunge and just have complete free flow but yes would will deff need a resonator maybe even 3 idk ive seen it on celicas why not eclipses

 

[rstare]

Well here is what is going to happen. The OEM manifold is very short meaning your going to put about 4 foot of pipe just to get to the cat. (Just a rough estimate)
I would keep the cat or get a high flow cat. I would also recommend just doing your exhaust from the cat-back because it sounds like you would like to get a "header" eventually, which would in turn replace this "front exhaust pipe" (the pipe after the manifold and before the cat). That's just my opinion though.

 

[tazman_tn]

well..... after thinking and talking to friends, i think i just gonna eliminate the cat and go 2-1/2 behind the downpipe and leave the downpipe alone