Exhaust size on 3.5 A/C

[mattyfo0z]

In the future, I was thinking about getting a custom exhaust set up from a local shop instead of one of the bigger name brands. Just for my knowledge, does anybody know what size the piping is on a stock A/C?

I'd probably get the piping a little bigger, maybe .5" or so, and I'd be going with a single exhaust setup instead of the dual the A/C has stock. Thanks for any help.

[mmx23z]

your gonna want 2.5'' piping, any bigger & you'll lose back pressure & low end

[mattyfo0z]

And that's with both 2.5 and/or 3.5 motor? I was thinking 2.5", maybe 2.75" max. I'm pretty excited.. I think I'll be the first A/C with a single exhaust (I haven't done much research, though).

Here's a rough Photoshop I did real quick. As you can tell, I suck horribly at making it look like nothing was there.. but it gives me a good enough idea.

[mmx23z]

And that's with both 2.5 and/or 3.5 motor?

3.5 motor only, 2.5 motors should do 2.25
but I only seen turbo'd cars running a single exhaust with usually a 3" exhaust (depending on vehicle), ur pretty safe sticking with 2.5" cause ur not running forced induction but good luck with it can't wait to see how it comes out! wat type of muffler will u be using?

imo I would angle the muffler a little more with the single, I think it looks better

[mattyfo0z]

Cool. I'll probably go 2.5" then.

I think I might just buy a generic eBay muffler, and save some money. The muffler shop here doesn't have anything very aesthetically pleasing, and I don't wanna spend too much on just the muffler. I don't have to worry about rusting or anything like that cuz I live in the SoCal desert.. so no snow or anything for me lol.

At the moment, though, I'm thinking a replica Greddy Ti-C muffler.

[CoupeVQ35CVT]

I would also recommend not going over 2.5" for your exhaust for the length of the mid and axle-back sections.

rant/
As for mmx32z saying a larger size would reduce back pressure which would reduce torque/power.... *FACE PALM* to self It is NOT back pressure my friend, it is the exhaust gas' escape velocity and the scavenging effect the faster moving exhaust pulses have that help the low RPM torque, NOT back pressure. Back pressure does not make power/torque on modern Fuel Injected engines from all the different articles I've read, and also using some bit of applied science/common sense thinking. It DOES help carburated and 2-cycle engines burn their fuel more efficiently (though strictly speaking "EFFICIENT" and carburation or 2-cycle don't go in the same sentence). /rant.


(NOTE: Personally I puke at the thought of single fart can mufflers for sight and sound, when the stock bumper has a diffuser setup for 2 outlets and leaves an unsightly extra "u" with one outlet, AND I hate what it does to the sound (Honda rice car) especially more so on our classier V6 VQ35 equipped cars, unless there is a turbo setup and then I can partially overlook the disgusting sound and retarded angled muffler.)

[downedzephyr]

(NOTE: Personally I puke at the thought of single fart can mufflers for sight and sound, when the stock bumper has a diffuser setup for 2 outlets and leaves an unsightly extra "u" with one outlet, AND I hate what it does to the sound (Honda rice car) especially more so on our classier V6 VQ35 equipped cars, unless there is a turbo setup and then I can partially overlook the disgusting sound and retarded angled muffler.)

[Oilsink]

do a single, just dont f*** it up lol

[mattyfo0z]

^ Haha... I won't. At the moment, I'm just trying to find a muffler that I like best.

[mmx23z]

It is NOT back pressure my friend, it is the exhaust gas' escape velocity and the scavenging effect the faster moving exhaust pulses have that help the low RPM torque, NOT back pressure.

i was pretty sure it wasnt bak pressure but i couldnt think of the specific name, & when while tryin to explain it i thought to matty it would make sene.

@matty: id run a greddy evo2 muffler! or have u tried looking on Craigslist see if you can find anything cheap on there, once u get the piping done id assume it'd be easy to just cut & weld any new muffler if you dont like ur 1st setup.