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How Much Boost Can The Unopened Rb25 Take?

Torques

By Torques,
in Engines & Forced Induction

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Torques Mentor

Torques

Posted
Posted

Hi there,

Considering there is no knock, or lean-out and so forth, how much boost is 'safe' on the RB25 without risking the head gasket or

other destruction?

I hear people running 20PSI with standard internals .. just wondering ..

bubba Grand Master

bubba

Posted
Posted

WHOLE WORLD

IMPLODE

EVERYONE DIE

But srsly, there is no specific number.. my Neo happily take 15psi through the highflow without breaking a sweat, on the limits of the injectors though. With bigger injectors I wouldn't hesitate to push 20psi into it.

Trozzle Grand Master

Trozzle

Posted
Posted

No magic number, though to put an end to this I think someone should connect a high volume air compressor to the intake right before the throttle body and crank it up until SOMETHING pops - probably intake plenum gasket or valve seals...or something, I don't know.

The Dan Grand Master

The Dan

Posted
Posted

Have seen 56psi on a standard gasket for well over 100 dyno passes and still going.

Depends on your tuner. Depends on head studs/bolts. Depends on what position venus is in the solar system.

It all comes down to how good your tuner is. The tuner we use is the best.....and yes, I will put money on it

tridentt150v Grand Master

tridentt150v

Posted
Posted

Knock is the limiting factor, if you can use high octane, WMI, or E85 etc then you can screw it on. But you will probably hit the knock wall eventually anyway.

And I've got no idea why two identical standard motors with the same power output and one knocks and the other doesn't - I know why there is knock, but why the inconsistency - luck of the build.

Trozzle Grand Master

Trozzle

Posted
Posted

Have seen 56psi on a standard gasket for well over 100 dyno passes and still going.

Depends on your tuner. Depends on head studs/bolts. Depends on what position venus is in the solar system.

It all comes down to how good your tuner is. The tuner we use is the best.....and yes, I will put money on it

I was hinting at BIG numbers :P more along the lines of 100psi

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