integrate

[QUOTE]Originally posted by NFRs2000NYC
I unbolted my exaust AFTER the CAT, and it was just deeped than stock.

DancingFool

I'm no expert, but isn't there a certain amount of back pressure (from the cat/mufflers) the engine needs in order to run optimally? I've heard this in regard to motorcycles, not sure if it applies to the S though.

jzr

I once had a single-exit Amuse R1 and I've also run the car with a side exit straight pipe from just past the cat (no resonator or muffler).

The car is UNBEARABLY loud with no exhaust. So loud you can't even think, much less drive well. With the Amuse the car sounded like a Camry in comparison. I have a couple mpeg's, will post them in a minute...

S2k426

Thats what i was thinking, but my friend has to have gains in his celica the car runs 15.4 stock and hes pullin a 14.7 with unbolted exhaust. I am hoping the S has gains cuz i am plannin on unbolting my exhaust as soon as i drive it off the lot.

jzr

I wouldn't unbolt the whole thing - just replace the big and heavy dual system with something single and lightweight that flows well.

Amuse R1
JZR-style straight pipe

The best bang-for-the-buck system I've run was a single Borla XR1 with some custom mandrel bent piping, all for $300. Saved about 35 pounds over stock and was still quiet enough to run at Laguna Seca with their 92db limit.

S2k426

Any power gains with the JZR-style Straight pipe?

HI SPEEDR

Don't do it. When you shut down your engine with your pipe opened at the head and fresh cool air rushes in when your engine is shut down YOU WILL BEND THE VALVES.

jzr

Probably, but it really isn't worth the headache. I decided it was just way too loud for my purposes.

FWIW I saw a peak 8whp gain from the Amuse.

Rapid cooling can bend exhaust valves when you run with no header at all, but that's not what we're talking about - we're talking about running no exhaust system past the end of the header. And even on our little 4 cylinders, it's TOO LOUD!

Halo

That second vid sounds like my friend's CBR with custom pipe

SJSHARKS

I have heard that if you remove the exhaust completely, you can overheat the head. The exhaust acts to dissipate the heat away from the head.

Use caution.