thunder85

iTrader: (1)

Hey all,

quick question. everyone is well aware of the rpm/power band issues regarding long runner based efi... how much of that is still present after the implementation of a turbo or super charger? does the addition of a compressed air source reduce/eliminate the 5k rpm power wall?

thanks for the input,

Jason

Sonix

iTrader: (1)

It certainly helps, but it doesn't make the intake runners a non-issue all of a sudden.
There are members on here running the TPI runners with a supercharger or turbo going extremely fast. They may or may not be hitting 6500RPM (typically not) but regardless, the power increase means they don't need to hit the high RPM. Meaning.... Who cares?

thunder85

iTrader: (1)

that answers my question. thanks

Dan W

The power band on a centrifugal setup moves the peak hp rpm point up because of how the boost continues to rise through the rpm range. The combination of a long runner intake with a centrifugal is a nice setup on the street in my opinion as it makes for a very broad power band although some peak power will be lost over short runner intake.

Anyway, I think this is less the case with turbos and certainly not applicable to positive displacement units as full boost comes on much earler and you dont have that boost increase with rpm. So I'd be more inclined to use an intake designed for the rpm's I'm trying to tune for in these applications.

thunder85

iTrader: (1)

excellent. thats honestly what i am aiming for... good street power. how often realistically do most of us push the rpms over 5500 in town or on the highway? i'm the kind of driver where i don't speed too much, but i love to get up to the speed limit as soon as i can... =) a good centrifugal on a longtube runner setup with some siameseing done seems to be the answer in my book. the increasing boost profile compensates at the higher rpm ranges for the limitations of the runner setup. Thanks for the input!