diff between MPFI and Tuned port? - Third Generation F-Body Message Boards

92RSMuscle · 04-24-2002, 10:11 AM

does anyone knowthe dif.?
i have a friend who said MPFI was called TPI, tho i dont believe him

thanks

mike

Drew · 04-24-2002, 10:26 AM

TPI is a MPFI setup.

MPFI = Multi Port Fuel Injection. Simply one injector for every port.
TPI = Tuned Port Injection. Simply each port has a tuned runner.

TPI setups have MPFI cast into them... the same MPFI by Rochester stamp that 2.8's and 3.1's share. However referring to a 2.8 or a 3.1 as a TPI engine would be inaccurate since they don't have the tuned runners. Some other GM engines share the TPI designation.