Slant 6 Turbo 68Dart Project

What does the Wastegate do and how does it work and what does the bov do and how does it work just assume I'm an idiot and put it in lamens terms for everyone else lol
Is a 390cfm holley a good carb to run with the turbo setup?

wastegate lets pressure off before the turbo so it doesnt spin enough to make more boost without one it would just keep spooling until your motor gave out.

bov lets the compressed charge release the pressure between the turbo and the carb.

if you can find a 390 double pumper it would work. cfm doesnt change because of the turbo. has to have mechanical secondaries. the vacuum secondary carb wont work.