How much Boost?


What's An Intercooler
Staff member
May 26, 2001
ok can someone please explain how you determin what the max boost level you can run in your car. i mean i know with my gn i run around 20 but i know my bros tuck is running in the 30's and i know ive seen supras 40+. can some please tell me how this works.

Don't have a formula that calculates it. But the best way to get to high boost is to control knock.

Many stock head/stock gasket/stock bolts cars out there hitting 30 psi boost with water alcohol systems or race gas.

Just keep knock under control. From my experience I've seen 30 psi in a factory shortblock. I know the racers run much more.
93 octane 15-18PSI depends on car, etc

116octane 35PSI ++ depends on car, size of turbo, etc.

Adding alky or water injection can raise the level of boost before knock.