2.50 or 2.25 piping, custom catback

[Projex0]

im planning on do a custom catback exhaust into a borla muffler in the end, would 2.50" piping be too much make it to little of back pressure for the gen 2 or would 2.25 be more ideal?

reason why i chose the borla muffler cause i was pleased with the sound it made from the axelback on my old matrix.

[CASTRO]

BAH! bigger is better. Who needs backpressure, go 2.5 or bigger. Honda guys with tiny motors get 2.25, our v6 needs bigger piping than that.

[Projex0]

so 2.50 is fine?

[CASTRO]

yep, 2.25 is just like stock. I dont think you wanna redo piping thats the same diameter as stock. if you wanna compare, the greddy is 2.75

[Projex0]

o ic well i was a lil worried in going into the 3" range which i thought is in the force induction area, but thanks for confirming it CASTRO

[CASTRO]

no problem. I'd say 2.5 is the minimum you should go, I'd go a bit bigger maybe 2.75 to be at least in the greddy range.

[PhreakdOut]

You will be fine with 2.5". Don't bother with 2.75". The tubing is rare and it will cost you an arm and a leg to get it. Besides, very few muffler shops have bend tooling in 2.75". Usually they have 1.5, 2, 2.25, 2.5 and 3" die sets. If you check, you'll see that shops charge less for 3" tubing versus 2.75".

Reality is that you will see little to no change in performance. The acoustics will change a bit. Larger diameter pipes will usually be deeper sounding. Sound waves expand more in larger areas and frequency drops.

If you're serious about changing performance, you'll want to focus on headers (eliminating the mani-cats) and a larger diameter front pipe. The 05+ Avalon pipe will work fine if you cut and weld (rotate) one of the flanges.

Good Luck!
- B

[Duyquach]

i did 2.5, and let me tell you....my gas dies out so quickly now lmao

[PhreakdOut]

i did 2.5, and let me tell you....my gas dies out so quickly now lmao

Please define what you mean:
1) MPG is bad because you leadfoot it everywhere.
2) You lost all low end power.

[Duyquach]

Well at first I thought it was because i was punching the gas just to hear the roar but i kinda got tired of driving like that, so i went back driving conservative. But I get a lower MPG, because my range drops down so quickly it's ridiculous. And the car is actually very quiet at idle, lower RPM = not that loud either.

[RDKamikaze]

for the 2.75" piping, you can always go to a small pipe shop and have them bend and cut it the way you want. If not, it was worth a try to ask.

[dominoSLEV6]

I have a 3" on my Supra and have the low end tq loss. I'd much rather not have it at the moment, but it's not that bad, and it's setup for when my turbo goes in.

-chris