Jump to content
SAU Community

Max Rpm With Stock Head ?

GreeceS13

By GreeceS13,
in Engines & Forced Induction

 Share

Recommended Posts

GreeceS13 Rising Star

GreeceS13

Posted
Posted

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!!

Link to comment
https://www.sau.com.au/forums/topic/282540-max-rpm-with-stock-head/
Share on other sites
rob82 Mentor

rob82

Posted
Posted
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.

GreeceS13 Rising Star

GreeceS13

Posted
  • Author
Posted

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!

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

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

Parag0n Mentor

Parag0n

Posted
Posted

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.

Deathwish Apprentice

Deathwish

Posted
Posted

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

zebra Grand Master

zebra

Posted
Posted
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.

Sheriff Wan Proficient

Sheriff Wan

Posted
Posted

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?

PM-R33 Grand Master

PM-R33

Posted
Posted
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...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • sunsetR33
      Unpeeling the Orange

      By sunsetR33 · Posted

      Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • Kapr
      What brakes on R34 GTT(Europe)

      By Kapr · Posted

      No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • wizlb
      Who has a Infiniti Q60, Q50 (V37)?

      By wizlb · Posted

      I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Kinkstaah
      Starting again

      By Kinkstaah · Posted

      Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
    • GTSBoy
      What brakes on R34 GTT(Europe)

      By GTSBoy · Posted

      I'm not going to recommend an EBC pad. I don't like them. Just about anything else would suit me better. I've been using Intima pads for a while now.
×
×
  • Create New...