The V8 Owners Forum -

So..

Can someone estimate that how mutch i can rev my 5,2L RV8 bottom end?
Its inc Ross forged pistons, Manley H-Beam rods, Forged steel crank..
Top end inc mechanical cam, and roller rockers..

I estimate that near 6500-7000rpm is absolute maxium..? rev limiting to 6500rpm?

Timo,

You will no doubt get lots of "I rev mine to xxxxrpm no trouble" responses, however that won't be to much help to you will it?

With your choice of bottom end reciprocating and rotating components I would suggest that they will not cause you concern.

Your maximum rpm will be governed either the amount of gas flow your heads can support at high rpm or, more likely, by the onset of valve bounce - loss of valve control.

In which case, if you fitted springs to the recommended fitted load and max lift load as directed by the cam manufacturer your best bet would be to ask them ! Anything else will purely be a guess.

Russ

I have my rev limiter set at 7K. I have diamond forged pistons, Wildcat H beam rods, Cast crank and a crossbolted block, A 256 cam and group A rockers and i have never had a problem through reving it to far. My mate in his manta has a normal block and real steel stroker kit rods (standard ish) and he has his rev limiter set to 7300rpm and not had a problem. Regardless of what anyone else says i know these are true figures and know that there hasnt been any problems due to over reving. P.S. And the manta engine has been running like that for about 6 or 7 years and still no sign of any damage or give.

The question is where is your peak power and how fast it tails off once past the max hp rpm. There is simply no point revving the nuts off the engine if there is no real power in high revs.

I know that my 4,6 engine gives max power at about 5900 rpm but it will rev to 6400 rpm limiter easily, probably higher. There simply is no point in revving higher.

What size cam do you use ??

I have a similar spec bottom end on my chevy (forged pistons and crank and H beam rods) and plan reving to 7800, I've 252inlet 263 exhaust on a mechanical roller cam it should give peek power about 7200 to 7300, the bottom end should be ok beyond this but as is being said above the limiting factor for me is the valve springs, I can go for higher revs with higher rated springs but the valve springs I have now have a life of about 60 hours. I could go titanium valves and ultra light tappets but that is very expensive! There is always a trade off
Mike