Rb20/25 Questions...

[SleepingTalon]

I have a question that I thought some of you could help me with. Im a tuner in the U.S., and I recently tuned a few RB motors, both of which made EXCELLENT power. Anyway, the first one was an RB20DET, it made 350whp (261rwkw) @18psi on pump gas, that's 93 octane here. The one I did last night was the RB25DET, and did even better. It made 395whp (295rwkw) @19psi on pump gas, 93 octane. My question is, how much boost do these motors take without the need for headstuds? Is 21psi safe on the stock head bolts? Does it need a upgraded headgasket with some ARP's? Also, how much power will the stock motor, on each of these platforms, make before having to upgrade the bottom ends? Lastly, how much RPM can you spin on each of these motors with the stock valvetrain? On a final note, both of these engines seem to make power with ease, and are great platforms from what it looks like to me. It's always fun to play with a different platform and see what it can do! Thanks again everyone!

[R31Nismoid]

remember yank dynos read a low more than Aust ones...

something in the types or whatever.

as for how much power they will take etc.

please search, all been covered many times.