Just a follow up from Gingerman - didn't want to start a new thread (hope you dont mind Dan):

Fuel vapors in the cabin is the main reason I pulled off at Gingerman, I would have tried to complete the race had it just been the clutch slipping. REALLY glad I pulled in. Once home I found no reason for the fuel vapor smell and siliconed the rear access panel shut as it had come off during the race.

I took the car to Nelson Ledges/944fest this weekend and got black flagged within a few laps on Friday AM - car was dumping A LOT of fuel out the back (right where the exhaust used to be until it fell off at gingerman) and we found a soft spot with a hole in the top of the tank. Strange!

Huge thanks to Ed Baus who provided the spare tank (and Brian Richardson/Andy Kihm who had it torn apart in about an hour) - we had it back running by Saturday morning.

Clutch slipping seems like it was the adjustment at the pedal, too close to the engagement point likely overheating the disc. Adjusted it to have some free play and It did not slip at nelson ledges, knock on wood.

Real glad the exhaust fell off when it did as otherwise it probably would have been a fireball. Off to buy lottery tix.

Sam, this is bizarre. I've never seen a late plastic tank go bad before. Any idea how this happened from looking at it? I am really regretting not running this car on the track before I sold it work out the bugs. I guess it had never been driven very hard by it's previous owner....

Yup, I was shocked as it was not drilled through or anything, there was nothing rubbing against it. These tanks are thick - and the area that was soft was pushed out - looks pressure related to me and there are signs of stress / fine cracks around the hole. Vent hose was open and not blocked in any way.

Here is a pic, as you can see we tried a quick patch with jb weld and a bolt to attempt to save friday but it immediately leaked so then the tank came out.

That's weird to see as well. I had a clogged vent, and developed so much pressure in the tank, that it distorted the trunk floor, without any leaks or soft spots coming up. I'm glad you got it fixed. It's pretty big job, though!

wow sam. Thats nuts! and lucky. Glad you got it all fixed- before it caught fire! See you at Autobahn?