ramtookrazy

i figure its an exhaust leak or a cracked exhaust manifold or something. my engine could be bad, which i hpoe to hell not but i dunno what else would explain the backfiring.

the smell and eye burning comes when i floor the car in 3-5th gear at low rpms. i have replaced precats with an 2.5in. rb downpipe. everything else is pretty much stock. my car is n/a. there hasnt been hangers under there for a few weeks except from my mufflers which are a bit rusted with holes. could all this be coming from my mufflers and y-pipe or is there something worse up front?

sorry if these are noob questions. searching helped but i kinda need more specific answers. thanks.

SonicRaT

iTrader: (6)

A combo of rusted exhaust/leaks in the gaskets, and probably bad shifter boots (under the leather one), also, exhaust will tend to work it's way in near the hatch area if the mufflers leak)

ramtookrazy

would getting cheap ebay fart cans be a good start to fixing the problem at least a little bit or should i just patch them up for now?

REnoob

i ran my 7 at the track with the exhaust off at the block, and it burnt a total of 11qts of oil upuntil it blew up... and never once did my eyes start burning, and it only backfired around 4k when i let off the trottle

ramtookrazy

would a cracked exhaust manifold cause this to come about this bad? leaking gaskets? sonicrat is right about me not having a good rubber shiftboot but would that have that much an effect on it? cause i havent really had a good one for awhile and this hasnt started until recently

2cute

My guess like someone else said would be a leak of some sort in your exhaust. . It is possible that since you said youi have no hangers that that has caused a newer worse leak than just the previous holes in the piping alone. I suggest you get under the car and see if you can find it and go from there.

vaughnc

If you want it cheap, check the local salvage yards for a used rx-7 exhaust for 86-91.

Sideways7

iTrader: (7)

Why would you ever take off the exhaust at the block? If you have ever seen a pic of a rotary running without the manifold, it shoots flames several inches out the exhaust ports. You prob. cooked several of the lines around the engine bay.

Sideways7

iTrader: (7)

I had an RB DP/presilencer without the hangers, and I had the same problem. How does the exhaust sound? Is it very raspy and kinda metallic, not like the exhuast used to be ? If so, I am willing to bet that you have developed a leak where the DP connects to the exhaust manifold. It starts as a small leak, then gradually vaporizes the gasket (even it you used RTV 650, i found). This leak is directly under the passenger floorboard and will leak up through shifter boot. The holes in the muffler will allow exhaust to leak in through the trunk/hatch, but it is very small compared to the other leak.
If that is the problem, just get a new gasket and put on a little super high temp gasket sealant as extra protection. Also, run by a junk yard and grab a new hanger. Or you could get a new one for not too much at racingbeat.com If you do that, get a gasket from them, too. They seem to be higher quality than the ones you get at parts stores.

2slow4stock

iTrader: (18)

Getting a exhaust from the junk yard from a 7 is a big no no since it would probably be rusted to hell and being stock with the 3 precats/cats, and even then it would probably bad, only thing good would probably be the manifold.

Sideways is right if you ran without the manifold then you probably burnt some wires, since in the engine bay it gets up to 1600'F at the most.

Sideways7

iTrader: (7)

I've got a pic of a 13b running out of a car with no manifold. I'll try to post it once I get home from work.

ramtookrazy

i fount the problem, YESSSS. sideways7 youre right my gasket was burnt krisp



im gonna have to get a new gasket soon with the gasket sealant. for now i used an old gasket i had on before.

Thanks guys.

2cute

i havent seen too many gaskets do that. i would definatly recomend getting some hangers

staticguitar313

iTrader: (2)

i got a two stock turbo exhaust systems for free in good condition, so you should be able to find something fairly easily.