FM Turbo Exhaust
This is a comparison of the stock exhaust with the first generation FM turbo exhaust. The FM unit is constructed with 2.5" ID mandrel bend stainless steel pipes into a 3.5" tip. The muffler is a straight through design.
In my experience, this exhaust is surprisingly not very loud. Even running naturally aspirated, this unit is only marginally louder than stock. The quieting characteristics of a turbo in the exhaust path further suppresses noise, that is, until the engine is loaded down. At that point, the exhaust gets a bit louder/deeper but still sounds very good.
After several years of use, the exhaust tip began to tarnish. It developed a blotchy appearance that wouldn't buff away by hand. I tried various metal cleaners and none of them did any good at really removing the surface defects.
I eventually got a wild hair to have the tip replaced. I bought a dual wall resonated tip in the same 3.5" diameter and had it welded on. At first, the tip wasn't on straight but I had the exhaust shop heat up the pipe and they bent it back into position.
I came across a used newer FM turbo exhaust system for sale and decided to buy it. Although my current exhaust is fine, I kinda wanted to get the original look back. I've been hearing a buzz and suspect the muffler has something loose inside. We'll see soon when the newer exhaust goes on...
The newer used system showed up and to my disappointment, the tip had the same tarnishing epidemic... although worse! I wish I had asked for pictures before the purchase.
My loss. Well, not exactly. Instead of hacking off the tip on this one, I decided to give a buffing wheel a spin. I should have done this in the first place. It turned out really well. Time will tell if the buffing will hold up or if the surface imperfections will show up again.
|Left side shows tarnishing; right side shows progress after first pass of polishing.|
I used a spiral stitched buffing wheel with an
emory compound for the first cut, then used another buffing wheel with a
stainless specific compound to get more luster. I could probably spend a
little more time getting it even better, but I think it looks good to go.