I'm hooking up a home job straight through exhaust without cat, muffler ect and just wondering what kind of performance increase (if any) i can expect with a 3k engine. also I'm worried about how loud its gonna be, any ideas?

 

cheers

performance gain = s.f.a

 

noise = LOUD

 

had something similar on a motorkhana car and it did nothing.

Billie (our 55) has effectively got a straight through exhaust, just a huge-ass cannon on the back that I think does SFA to lowering the sound. Gave me quite a shock when I stuck my head under there and just saw a long unbroken pipe running straight from the exhaust manifold to the back of the car. The guy I bought it off said he did it as practice for a project he was working on, and everything has held up fine (plus it passed rego, although I doubt the EPA would like it).

 

As for performance gain, wouldn't have a clue as I haven't driven the car with a stock exhaust, but considering the minimal amount of power in a K series anyway, and the big restriction of the 8V non-crossflow head, I seriously doubt there is a lot of power locked away in the exhaust

so maybe jsut straight through from midway, so keep the cat and just take replace it after it loops over the axle just before the muffler? my mate just got a 84 corrolla and took the exhaust straight off and they rekon the performance increase is amazing, would be a different engine i guess.

don't get performance gain and noise gain mixed up. If its faster against a stopwatch them good luck to you.

 

Running events straight out of the engine pipe (don't ask) did not seem to improve anything either.

 

Best system I had was a set of 4-1 extractors, a 2" pipe that went under the diff housing into a 2nd hand muffler with a 3" pipe welded to it :lock_folder:

 

That gets people scratching their heads about whats in it. Lost count of the "how does the rotary go?" comments

3ks don't have cat converters bro.

yeh i guess I'm used to looking at different cars, but usually i would think running a straight pipe through instead of having mufflers and other restriction would help performance.

It's a 3K. It'll make bugger all difference. I should know, I've built a few.

 

Put a straight through muffler on it, that way it might end up somewhere near legal.

mines a 4k with 4 - 1 extractors and 2 inch with resonator and cannon.

 

dunno if it makes any more power but it reached 110dB on a radioshack dB meter at roughly 3 feet away lol

wank factor :lock: :lock_folder:

Well said Robert.

seriously as people have said, its only a 3k motor, no point in doing it.

 

probably the biggest waste of time since night shade on tail lights.

lol, yeh like i said before, I'm not used to these engines.

I'm only intersted in doing my exhaust to achieve a certain sound I'm chasing..

 

you know how some exhausts have a bit of a "bubble" (probably the wrong word for it) as they go up the revs?

 

i originally thought it was a cannon that did this, but all that does it make it loud, and much

deeper than i want it to be....how do i get that bubble?

^^like a gurgle? from my experiences cannons arnt good for anything but drone.