Just finished up a big Sami project. I'm running a 1.6 16 valve with a ceramic Doug Thorley Tri-Y header, hi flow cat, and a full 2.5" exhaust with a turbo style muffler. My header is starting to turn a tan color with some blue. Is this normal for a ceramic coating? I know chrome will do it but I'm unsure of ceramic. Just want to make sure my engine isn't running lean.

The other problem is that I'm running a 15 gallon petroworks tank. I've eliminated the charcoal canister on the firewall. I have the vent line going over the side of the tank and down about 6" with a simple fuel filter on the tip to keep anything from going in. I get a really bad fuel smell inside and outside (no leaks anywhere). The other issue with this setup is that I have gotten a few drops of fuel out of that vent line with only 5 gallons in the tank so far. Should I put a smaller tip on my vent line or possibly run it in the frame rail?

Thanks

I am just guessing on the header, but I think they will all discolor. You eliminated the canister that absorbs the smell from the vent line and I doubt the fuel filter will work as intended as fuel can flow both ways in a fuel filter correct? Just not as fast. Do some experimenting to see. The charcoal canister does have a few redeeming qualities.

If your exhaust does not leave the body in the stock location you get a lot of fumes. The samurai has the arodynamics of a brick. Anything exhaust leaving the samurai under the tail gate gets sucked right back into the cab (top or not).

The tank vent is a tough one. If it gets warm, the fuel and vapor expand, so you will get a raw fuel smell from the vent. If there was any fuel in the vent line it's probably compounding the problem.

FWIW,
We always run a cat converter when we can (cuts way back on exhaust smell). The charcoal canister is pretty easy to hookup if your suing any type of stock manifold. I highly recommend that for the tank vent.

I don't have an exhaust smell in the cab. I use a cat and have a downturn pipe after the muffler that extends past the bumper. I haven't noticed any exhaust coming into the cab. I really don't care about the header discoloration, just want to make sure my engine isn't leaning out as I do have a rather large diameter exhaust and a cone air filter.

I am using the stock 16 valve intake manifold but no longer have EVAP purge or EGR usage, all of that plumbing has been removed. I know that the charcoal canister is really the best way of getting rid of that fuel vapor smell. Just curious to see if anyone has a good way of minimizing the smell from the tank.

Yep, all of the D.T. Suzuki headers we have seen discolor, normal. :p

thanks for the tip on the header:D

If you're running a true 2.5" exhaust then it's too big. You need more backpressure. With the GSXR's a 2 inch should be perfect. You can reduce the exhaust size with a 2 inch coupler or a 2" restrictor plate. That way you don't have to change out the whole exhaust system. An exhaust systems diameter is only as large as it's smallest diameter section. Runnning too open an exhaust will cause leaning out of the mixture on off throttle decceleration to the point where you will be getting unburnt fuel in your exhaust. (will also cause the exhaust to smell really strong like fuel) If you are running a cat, then dumping unburnt fuel into it will glog up your cat really fast. A clogged cat well cause the opposite problem of too much backpressure and you stand a good chance of warping the deck or the exhaust valve seats from overheating. The tank vent line should never have liquid fuel in it. The charcoal canister wasn't designed hold liquified fuel. Do you have an overflow bottle at the filler neck to hold spill over from the tank?