overkill

I was messing around with my greedy boost controller and was reving up my engine to check my boost patterns and found what appears to be thin, pieces of metal that had shot out my exhaust. It was slightly curved , not flat, suggesting that it may have come from my exhaust or resonating MP. One side of the metal was heavily caked with exahaust while the other side was corroded and rusty. I check my exhaust with a flashlight and it was really clean, no evidence of mising metal. I though I remember inspecting my reso MP before installing and it looked intact too. Anybody know what these peices are or had this experience?

Maximum

iTrader: (5)

Sounds like a side seal! haha jk but about what size was it? Also, what type of muffler do you have?

yuichiror

iTrader: (1)

How do you know it came out of your exhaust? Did you see it shoot out, was it in the tailpipe? Isn't a RMP packed with "wool"? Could something from the engine make it past the MP and muffler?

overkill

exhaust is the apexi dual. largest piece was around 1" x 1/2".

overkill

I could tell it came from my exhaust because there was several metal pieces. They all were in a line right behind the exhaust tips. it was pretty obvious where it came from. the only logical explaination is that its either part of the exhaust or mp, but they both looked really clean- not corroded.
btw, I was backfiring a few times, and I'm sure that is what caused those peices to shoot out

overkill

i'll post a picture of some of the debris tomorrow

Cgotto6

iTrader: (8)

Ive shot pieces of my broken down cat out my tail pipe. Im not sure if you even have a cat...Its possible its either the resonated midpipe or muffler though. Ive seen both of those happen.

Haha, yea just read what I wrote...You have a resonated midpipe and not a cat so just forget the first part of my post...

David Beale

I suspect you are overheating the mid-pipe resonator. It's probably designed to go further back where the gas is cooler (it's a small performance muffler, no?). Nothing to really worry about - the car will slowly get noisier. Just note that if it totally fails it could plug. You'll notice that right away as you'll loose power and boost - you may even not be able to transition to the second turbo.

overkill

That sounds like a plausible explaination in regards to the resonator/muffler needing to be farther to the rear. But if for some reason the resonator would clog, its still a 3" straight MP, so yes I would get louder, but there would not be a a difference in flow.

Here are a few pictures of the largest piece. It broke in half, so you are only looking at half. Judging from the curvature and the fact that it only has carbon biuldup on one side, it must be from the exhaust/mp. I dont think it is part of the exhaust manifold, but was wondering if its possible that it came from the hot side of the turbos???

P.S. One last thing that confuses me is that if it did come from my exhaust or MP, I thought that the Apex'i N1 duals were contructed out of stainless steel which should not rust, right? I was told that my MP was stainless as well.

quicksilver_rx7

I would put my money on it being part of the exhaust pipe rather than the turbo hotside.

David Beale

While the exterior of "stainless" exhaust components are stainless, some of the interior baffles etc. may not be. They build them to make money, not stand as timeless wonders of stainless steel. Note as well that the 400 series of stainless will rust, whereas the 300 series will not. The 300 series contains nickle, chromium, and some other elements in trace amounts. The 400 series has much more iron in it. You can see surface rust on it after limited exposure to the elements.

The piece looks like the inside of a pipe. I don't recall any thin steel or iron parts on the turbos. Is the air injection tube still installed? Could be from that or from a baffle in the muffler. The baffles are made of perforated tubes with perforated plates.