Rpm Opinions

[The Mafia]

Hi everyone.

I have a internally standard RB25. Just wondering what a safe RPM is for it.

Standard Cams

GT3037 550hp turbo (.82 rear) 18psi boost

Injectors (555cc)

Excellent Tune that shows no signs of knock at all

Full exhaust etc.

How safely can I rev it, and what would be a good limit? 7500? 8000?

It pulls all the way to 7000rpm, and wants to keep going. (ie, doesn't run out of puff)

Any hints suggestions, weak points etc would be good.

Edited January 15, 2007 by The Mafia

[Angus Smart]

dyno? where it stops making power and about 500rpm above that?

depending on if the engine will hold together!

Edited January 15, 2007 by Angus Smart

[GTRgeoff]

But basically no further than 8K as that is about the limit of the top end. If that thing is making decent power at 3K then you should be shifting a bit shorter to use it instead of revving the ring out of it in the interests of longevity.

[The Mafia]

sounds ok, well, do you think 7500 will hurt it?

I love revs

[R31Nismoid]

I'd be more inclined to worry about the rod bolts letting go or something similar.

I ran mine at 8000 with rods/bolts in the bottom end and it was ok.

But if you want to err on the side of caution i would stick to ~7200/7300

[GTRgeoff]

7500 will be fine Jono unless there is already a fatigue flaw present, and you would no doubt have found out by now. In fact plenty run to 8K without issues but again, that is the limit of the head before the hydraulic lifters start to give problems and float, not a bottom end problem.

So what experience hve you had with rods/bolts letting go in RB25's Ash? It isn't a common failure by any means.

[MR331307]

7500 will be fine Jono unless there is already a fatigue flaw present, and you would no doubt have found out by now. In fact plenty run to 8K without issues but again, that is the limit of the head before the hydraulic lifters start to give problems and float, not a bottom end problem.

So what experience hve you had with rods/bolts letting go in RB25's Ash? It isn't a common failure by any means.

If you want it to last 7500

if not over that

I used to rev mine to 8000 8200

didnt snap any rod bolts

just bent a rod

Like a BANANA hahahaha

[GTRgeoff]

Have you made a note in my thread below? Have you grabbed some photos of the gudgeon and big end? It's not particularly common.