exhaust question (not in exhaust faq)

[sd88supra]

i have an 87 n/a and i wanted to upgrade the exhaust. i was thinking of gutting my cat, sticking with the stock 2.25" piping and putting in a flowmaster 40 muffler. would using the stock piping work well with the n/a? i read in the "exhaust systems researched" thread that 2.25" pipe without a cat is the equivalent to 2.5" with a cat. since i am a starving college student, i wanted to stick with the stock piping since i dont wanna spend too much $$$ on a new custom exhaust. i dont expect a large power gain, but id like my exhaust a little more free-flowing, free up a couple horsies.

as for emissions, ill just throw a cat back on to get it smogged

would there be any issues to look into (engine-wise) when not using a cat?

[mrnickleye]

You should be ok with just 'gutting' the old cat. Or you could get a 'test pipe' to stick in place of the cat.

Either way, the exhaust will be louder.

[rnoswal]

BUY A HEADER!!! That will be the best thing you can do for the exhaust. If the engine is stock and N/A then keeping the system close to stock size is best. I gutted the cat and put on a nice free flowing muffler on the back of my daughters 87 N/A and it sounds real good. I have the same system on my Turbo and it is quite a bit quieter due to the turbo muffling the exhaust note. My daughter drives the N/A and I love the sound hers makes when she pulls up and when she leaves.

The straight six has such a nice sound to it. The only thing better is a V12. I would like to hear an exhaust that exits in front of the rear wheels, shorter and meaner sounding I bet.

Russ

[Supra2NR]

wasnt there a video here of an mk3 with a side exit exhaust?

but i love the idea of giving your daughter a loud car
that way
you dont jus love it

I love the sound hers makes when she pulls up and when she leaves

when she comes and goes

you'll also know WHEN she comes and goes

oh, thank you, im gonna keep that in mind when i have mine

[sd88supra]

ive been reading up on mufflers and i was aiming to get a flowmaster 40 which apparently aren't straight thru design. straight thru design i guess is best (helps increase exhaust speed). i was thinking of going with flowmaster for a deep tone (i hate fart can rice mufflers), but how does the tone and volume (and performance) of a flowmaster compare with a magnaflow? a lot of magnaflow guys tell me flowmasters are nothing but name and are better suited for american muscle cars. if the sound is too loud i suppose i could add a resonator (as mrnickleye did). and i remember isphius saying he didn't like his magnaflow... open to suggestions/opinions

[rnoswal]

Don't worry about it sounding like a can of bees. The four cylinder cars almost always sound that way. The six cylinder cars sound more like a really nice tuned exhaust on a large four cylinder motorcycle. Some can be very loud but the six cylinder has the 2 extra exhaust pulses that soften the note. V-8's usually have one side separated from the other and have a nice rumble but still loud. The 180 degree headers for a V-8 race care sounds really nice though with all the exhaust pulses merging together like the cars at Daytona.

You almost can't get too loud with a small six like the Supra, but the exhaust can build up an annoying resonance at certain speeds. I went with a flowmaster on both cars and like I said, I like the way my daughters car sounds the best and that is without the cats on both. We can still get away with that here in Louisiana.

But I really don't even worry about the noise because of how loud most Harley's are around here. If they don't get pulled over for drag pipes on the bikes, then there is no way our cars can get pulled over for noise, just for acting crazy, which can be fun!

Just make sure the rubber mounts are used and not solid mounts. Go solid and you will feel it in the car as well as being too noisy inside the car. A good sound system helps, but not all the time.

Russ

[sd88supra]

would there be a significant difference (performance wise) between the straight thru design (like a magnaflow) and the flowmaster 40? from what it seems the flowmaster sounds better but people like the magnaflow better for performance. i suppose there couldnt be too much power difference since mine is n/a, and ill be gaining a little more gutting my cat.

[mrnickleye]

The exhaust manifold on the N/A was designed to give the engine more low end torque. Street/daily drivers won't gain with a header because it will loose some bottom end torque (what gets you moving from a stop at lower RPMs).

I like having low end power, and very seldom rev past 5k.

[rnoswal]

What he said is true about the stock manifold, but it is weird that Toyota built it that way but made the intake manifold valve open at around 4000 rpms. Just when you start making some high end power, the exhaust restricts it, then it falls flat on its face. I guess it depends on your goals for driving on the street, everyday driver or performance. There is always a trade off.

Russ

[Isphius]

Flowmasters actually completley kill hp on high powert cars, I was reading a test where they bolted some onto a 1000hp supercharged corvette and they choked it down over 200hp over just 3 inch glasspacks. But on a supra, Youd still gian quite a bit of flow over the stocker, But yes a straight through glass core or other type of muffler will flow best, and also be loud. Heres a video for your listening... 2.5 inch meinike exhaust pipe, magnaflow 2.5" fiberglass core muffler (very stright through, you can see out the other side) and a stock 7mge...

http://videos.streetfire.net/video/4...3600db0c59.htm