What is the best size mid pipe to get on a N/A setup? I have searched all over the forum but nobody gives a clear answer. I curently have Injen CAI, MMW header, TRD Exhaust, and i have no plans for F/I if that is of any benefit.

 

2.5 in.

 

2.5 in.

 

i have 2.5 from the cat back and its nice

 

2.5 If you plan on ever getting spray or head work done, otherwise 2.25 is the best for NA. I personally put on a 2.5 so it was ready for when i upgrade. I did loose low end torque thoe being NA. Just remember when you are not forcing induction you want some back pressure.

 

QFT, and I have the proof....

 

So 2.25 is the best across the power band. That means i should just stick with the oem mid pipe since it already is 2.25 right?...

 

Well yes and no.....The size is right but the stock pipe is heavy and incorperates a secondary cat and resonator. Upgrading to a lighter S.S. exhaust with no 2nd cat will improve performance across the power band. Keep the resonator thoe to tone down the rasp from deleting the cats. Best bet is to have a pipe fabbed up at an exhaust shop. Woun't cost much at all just for a mid pipe. If your exhaust sounds good now I would just leave the stock mid-pipe on. I have the MEGAN mid-pipe and its too loud with my current exhaust set-up.

 

you have a mmw header/s-pipe right? i think that's a 2.5 inch pipe right there, so you might want to consider getting the 2.5 inch.

 

I would agree. im running alpha werks headers, 2.5 S pipe, 2.5 customer exhaust. top end pulls so much harder. I was running stock S pipe for a while and felt that it was choking. once the s pipe was installed, there was a great difference. No numbers as far as dyno slips. but the difference is there. your ___ dyno will tell you Good luck

 

Since you say it pulls harder at the top end did you loose low end tourque and HP.

 

less backpressure usually == less low end torque.

 

Good to know. I guess im gonna stick with my OEM and mybe later get a custom 2.25. Cuz my header sort of stripped my tc of its peppy acceleration, and this way i can keep whats still there.

 

Less backpressure usually = more power in FI engines right?

Im getting ready to install my MMW header and S-pipe and am still kinda worried about loosing that low end torque, even with the s/c.

 

If you are s/c I really wouldn't worry about it. The header and s pipe will greatly benifit you.

 

I'm still N/A at the moment and when I installed my header and exhaust I could notice a change of low end pep. My cars all top end now. Kind of sucks when just crusin in and out of traffic.

 

Once i get it in, im going to have a mid-pipe done by an exhaust shop (2.5in.) to connnect it to my injen axleback. I'll let you know about the change in low end torque.

 

Just remember to have a resonator or two welded in the mid-pipe. I have one resonator and also have the injen exhaust.......still raspy!!!

 

^Yea, Im def. gona have a resonator installed

 

yes i did unfortunately, but it usually picks up around 4k. off the line i get tire spin depending on how i am launching. second gear again spinning. and this is with the stock tires. but i would neve go back to the stock s pipe. you should definitly add a 2nd resonator if you have headers and no cat. it so raspy it will drive you nuts.