I have an 85 GSL with some random mods done to it.

All I really want to know is if there is a good modification that I can do to the overflow tank to make it better. Mine has popped its cap off randomly a couple times, and Im tired of it. (I was surrounded by police yesterday because someone called in my car being on fire because of the steam :P I shut down right after it happened, so there shouldn't be any damage) The cap is slightly worn, and stress marks are visible on it. Any ideas are appreciated. My backup plan is to yank the one off my parts car.

 

buy a aluminum overflow.
look them up on the internets, or go around to some performance shops.

 

Yea that cap needs to be snapped on like from left to right with a good amount of force. I always think it's gonna break. Just a poor design. The alum is good idea. I have seen those for C4 Vettes and what not but not custom fitted for FB's. We always get a bad deal from some of the performance parts people.