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In the head of my rb26 I have only hks cams 272 9.3 !

What is the max safe rpm that I can run it?

My block has everything to run very high rpm I think (nismo oil pump, oil return, ati race pulley etc).

I am thinking to run a T51 SPL BB or T88H-38GK that both is for 1000+ HP so I need some rpms to run it in good rpm!!

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In the head of my rb26 I have only hks cams 272 9.3 !

What is the max safe rpm that I can run it?

My block has everything to run very high rpm I think (nismo oil pump, oil return, ati race pulley etc).

I am thinking to run a T51 SPL BB or T88H-38GK that both is for 1000+ HP so I need some rpms to run it in good rpm!!

Suck it and see - keep reving it until the power drops off or it starts to vavle float either way if every thing is built correctly then you wont hurt anything.

I don't want to test it :rofl:

I would like to tell me if it is safe the head for example 9000rpm. I think that 9000rpm limit for theese turbos is good to give me a satisfactory power range, right?

I read that theese turbos starts at 5000rpm! So 5-9 will be the power range!

How long is a piece of string?

Some heads are in better condition than others, so some can take more RPM for longer than others...

Its really a question that cannot be 'answered' accurately when you want to push something. Every setup will fail at a different point to the next when your talking 10-15yr old heads

Really no point revving past 8ish? Would a T88 still make power after 8k? You'll get a better understanding once you have the turbo installed and find out when your peak power / revs are.

But to answer your question on 'safe' I wouldn't take it above 9000rpm often.

Hi mate, i've got a standard engine in my car with a race head gasket and a big turbo on my Gts-t and all the supporting mods for making bigish power but as it is standard it probably wont do much after 8000rpm without something going wrong. My turbo starts boosting at 4500 and im on the limiter at 7500 so its pretty laggy shall we say lol. If you want to run higher rpm your're going to have to fit forged internals and i lightened, balanced crank as well as solid lifters and probably some porting and polishing too. Thats what i had on my old engine and it used to rev to

10,000rpm all day long, it was much easier to make the big power with the higher rpm.

Regards, Thwish

Hi mate, i've got a standard engine in my car with a race head gasket and a big turbo on my Gts-t and all the supporting mods for making bigish power but as it is standard it probably wont do much after 8000rpm without something going wrong. My turbo starts boosting at 4500 and im on the limiter at 7500 so its pretty laggy shall we say lol. If you want to run higher rpm your're going to have to fit forged internals and i lightened, balanced crank as well as solid lifters and probably some porting and polishing too. Thats what i had on my old engine and it used to rev to

10,000rpm all day long, it was much easier to make the big power with the higher rpm.

Regards, Thwish

Did you even read the OP's post? How does your standard internal Rb25 have anything to do with Greeces13s built 26?

A decent set of valve springs and retainers are a wise investment on any big power engine regardless of revs.

mmmm DeathWish

"If you want to run higher rpm your're going to have to fit forged internals and i lightened, balanced crank as well as solid lifters and probably some porting and polishing too"

The RB26 has solid lifters as standard, agree with zebra on this one - you havent helped much.

To the OP - I would go to your engine builder/tuner to work this out. As its already been said there is no magic number based on a few lines about your car as to it potential.....

I could tell you it will rev to 9,456 rpm but what difference would that make if I havent seen it?.... Get my point?

Hi mate, i've got a standard engine in my car with a race head gasket and a big turbo on my Gts-t and all the supporting mods for making bigish power but as it is standard it probably wont do much after 8000rpm without something going wrong. My turbo starts boosting at 4500 and im on the limiter at 7500 so its pretty laggy shall we say lol. If you want to run higher rpm your're going to have to fit forged internals and i lightened, balanced crank as well as solid lifters and probably some porting and polishing too. Thats what i had on my old engine and it used to rev to

10,000rpm all day long, it was much easier to make the big power with the higher rpm.

Regards, Thwish

*Sigh*

  • 2 weeks later...

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