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being on a budget build, I would like to know what's the max HP for OEM internal ?

I'm fitting a crank collar and rebalance the crankshaft with a N1 pump and ATI 1000hp damper. I'm also buying a metal head gasket, I'm running a AEM Water-methanol injection and HKS GTSS. I would like to boost up to 23psi,maybe 25psi.

For the rest, I'm wondering if it's really worth putting the whole set of ARP stud, forged rods,piston, port the head, machine everything when I track the car once a years and do maybe 10-15 drag run per year.

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Depends on the tune,

what fuel are u going to be running?

If u keep the oil and coolant temp down by using oil cooler etc it will help alot.

U can run high boost on a stock moter as long as the peak pressures inside the combustion chamber are kept safe. If there is any detonation then the pressures will sky rocket way beyond a safe limit for the stock pistons, where as forgies u have a little but of a safety barrier.

So keep the tune safe, use a good fuel, and keep the engine temp cool

Depends on condition, number of km's and how hard it has been stressed and serviced over its lifetime.

It also depends on what level of tune you are going to run it at and how well you yourself take care of it, there have been stockers go 9 seconds but generally those are more of an "I told you so" exercise.

I'm disappointed someone hasn't said over 9000 yet to be honest.

well if it's in good nick it will run whatever the turbos will flow at 25psi. having said that on stock pistons 25psi is a fair bit of boost. I'd be looking more like 20psi-22psi with your stock engine with metal head gasket. like the guys said though it's a bit of a lottery. it may last forever if you keep good oil in it and run a good oil cooler etc and keep temps under control, or it may spin a bearing first track day out. only one way to find out.....

yeap, everyone so far is spot on, my motor when i brought it was running 20psi with N1 steel wheel turbos, i drove it on the street for 12months, (its my second car so i dont drive it much) and did one trackday. When i took it to the dyno for Jez to tune, once tail pipe A/F and the A/F guage was put in before the cat, they wouldnt even ramp it up under full load on the dyno, it was too lean.... we didnt even do one run they started adding fuel straight away.... so who no's what A/F ratio it was running and what they did with the tune before i brought it, the night we were tuning was only 20deg too so the engine was nice all cool, compared to the 35deg day i did my trackday at eastern creek, my oil temps where up around 125-130deg and my water temp got to 100deg when i was pulling off the track.... she was deff running hot!

The engine now has been tuned twice, and comp test came in at 150 across the lot, and that was a cold engine. shes a solid 311rwkw on only 18psi. and has lasted 1 night at the drags and a trackday at mdtc, and a far bit of street thrashing, so far, so good, i call it a freak as most rb's would have spun a bearing or shit em selfs in some sorter way. I always run good oils in my enigne (redline) and its changed before and after each and every trackday, i also make sure i do a warm up lap, and a cool down lap if the temps are starting to build. Oh and dont forget the 1L overfill if u plan to use the stock sump.

If its a healthy engine and you look after it, with quality stuff, it will last.... 25psi is a diffrent story but....

im running 22psi in mine with stock internals and N1 turbo's, in my opinion its safer to make more power with more boost but less timing than to run a lower boost and max it out with timing,

like i said in my 1st post its alot about the condition of the tune,

you can kill big end bearings with detonation not just oil starvation

Yep mine dropped a ring on 24 psi so maybe not that much boost, that was on a safe tune as well, car made 280RWKW but the boost was at 24psi through thr mid range and bled off up top as the injectors couldnt keep up.

Id say i was a touch unlucky though, it only lasted 4-5 thousand kms,

  • 10 months later...

I'm gonna give it a shot on mine, everything is changed except pistons and rods (new headgasket, arp headstuds, bearings, rings, etc. etc..).. tune/fuel/oil/cooling will be spot on so we shall see.. i'm aiming for 500whp max.. I had sr20's running 350whp daily with zero problems.. I dont see why this bad boy wouldn't hold more..

being on a budget build, I would like to know what's the max HP for OEM internal ?

I'm fitting a crank collar and rebalance the crankshaft with a N1 pump and ATI 1000hp damper. I'm also buying a metal head gasket, I'm running a AEM Water-methanol injection and HKS GTSS. I would like to boost up to 23psi,maybe 25psi.

For the rest, I'm wondering if it's really worth putting the whole set of ARP stud, forged rods,piston, port the head, machine everything when I track the car once a years and do maybe 10-15 drag run per year.

Given the amount of work you've already committed to, IMO its worth doing the rest and doing a full rebuild (without head porting, which AFAIK its a poor value mod at GT-SS level). Since the motor is out and you're taking the crank out, you'd do the mains and big ends while you're there... might as well just finish the job.

If it were my money I'd just do the balancer (since its a bolt on) and push the GTSS as far as you can (so no set psi figure) with a safe tune. Run an oil cooler/use quality oil/overfill sump. Don't rev the crap out of it.

Also, I assume when you're asking "will it survive", you are asking not specifically if your engine will survive, but something more like "assuming the motor is in good nick and I do all the things necessary to look after it (safe tune, dont let it starve oil etc) will there be a good chance it will handle that power level for a couple of years".

IMO the people in this thread have been too caught up in "every motor is different, we dont know how good your motor is, we dont know how you drive it" sort of thinking, which, while it is all true and valid, doesn't help OP at all.

My best guess is;

-7, -9, GT-SS = ok on a good stocker (with all the caveats)

-5 or more = full rebuild with forged pistons

My Rb26det has been making 475rwkw (638hp) @ 26psi for over 6mths with to4z and e85.

Forged pistons

Std Rods

Nismo bearings

Std short nose 32 crank

std oil pump

std balancer

MLS HG

Std head bolts

tuned by Sean at Efi

OEM Nissan parts are tough.

So many 300 - 350kw engine builds are so over engineered (

workshops and machine shops must be making a killing)

Biggest factor effecting a motors lifespan is the TUNE IMO!

ps currently upgrading, rods,crank, oil pump and going for more power.

Edited by 800KD

There's another thread around with someone making 444rwkw on a internally stock RB26, bar new OEM rings and bearings?

There's also threads of people increasing boost by 2 psi and needing a rebuild....

There's another thread around with someone making 444rwkw on a internally stock RB26, bar new OEM rings and bearings?

There's also threads of people increasing boost by 2 psi and needing a rebuild....

And plenty of stock motors have blown up too. We need know the how many and the how of the failures to be able draw useful conclusions.

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