Slightly related to discussion in "Main jet" thread... Here's some food for thought if you are designing a system for high boost pressure (relative term, I know). It would be a good idea to think a bit about forces that pressure applies on the plenum. So take a largest surface of your plenum, or any other pressurized part of intake system, and calculate how much force planned boost will make on it. You may get surprized if you haven't thought about this before   To get some fun for thi