Plenum chamber??? is that kinda like a flux capacitor??? hahaha, jk.... I honestly have no clue what that part does or how strong it needs to be, but I would suggest using carbon fiber over fiberglass if you need a very strong composite... It will give you better strength then fiberglass but It will cost more... try building one up w/ fiberglass then make the final product in CF.... Then I guess hope for the best... hahaha... good luck!
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...don't crush the weasel...
honestly you would be better off paying to have one made for you, it would have to be realtively thick as well as VERY smooth.
not to mention it would be much heavier and wouldn't withstand heat as well.
IMHO, I'd shy away.
Absolutely not. Don't waste your time.
FG can take a lot of pressure but it is not reasonable designed to work as a plenum for a supercharged motor. The vibrations, heat, and heavy pressures from the SC will make this a unwise choice, particularly over 7 lbs of boost.
Another major concern is maintaining perfectly clear and smooth inner surface to the plenum. Minor flaws and loose particles as time goes on could end up inside the motor and sending you out for a new longblock at the very least.
What vehicle are you planning on, or better yet, what's your motor? There might be someone here who could get you the information you are looking for, if not me.
Ganbatte ne!
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Never send your ducks to eagle school.
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