Rb26 Oil Mods

[duff]

I just done the OP GP and was hearing 2-3 engines have failed. That's 5% of the cars. Now since returning from the track day im hooked and now looking for my next track day. However anyone who is running a modified engine will always have in the back of their mind "will my engine fail because of the oil". I plan on doing more track days in the near future but is it worth pulling the head off and opening up the oil galleries and putting in the restrictions. How much do workshops ask $$ wise for this type of job. Or do i just wait for the bearings to fail then rebuild it with forgies and put the oil mods in at the same time. i know that to do all the oil mods the engine will have to come out. If i can help it i really dont want to ever rebuild my engine (not looking forward to a 10k engine rebuild), but rather take preventative measures. i did overfill it by 1 liter on the track day and installed an oil cooler but that's all i can do atm.

In the near future the car will be tuned for around 270kw if that matters.

[GT-RZ]

prevent failure. don't wait for it.

[R31Nismoid]

270rwkw on what turbos?

with that much power, as long as you overfill the sump by 1ltr you should be perfectly fine.

A stock RB26 wont last forever regardless if your tracking it. It'll last a year, maybe 3... but ye - most have not lasted forever unfortunately.

[NickR33]

tough decision... to do the oil control mods properly it means modified sump (and oil galleries etc) so is an engine out job... to drill the oil galleries will require the block to be stripped and cleaned and put back together with new bearings etc... To do all that is going to cost you several thousand dollars... and while its out you may as well get a new high flow oil pump and check the pistons etc... you may end up replacing piston rings and maybe even the pistons themselves depending on condition... then there is the head which while off you may want to check clearances etc... also a new set of gaskets, studs blah blah will be needed to put it back together... soooooo before long you will have spent over 5K just on 'preventative' measures and maintenance

I reckon you just keep overfilling it, keep the rev limit sane and start saving for a full rebuild down the track... hopefully you get a few years out of it before it cries enough... you WILL be needing a rebuild at some point with regular track work but how long you get is anybodies guess... if it aint broke don't fix it!

oh are you running the standard ceramic turbos? if yes you will want to swap them out when you pull the motor to do oil control mods

[duff]

im running hks 25/40 turbos so they are steel wheels. Holy crap didn't think preventative measures would cost that much. How the hell did Nissan build such a good car and F#@k up the oil part. From what you guys are saying from 50 cars that start the track day, an average of 1-2 will die is the norm. Now that sucks. Oh and now i know why my 3 instructors were trying to get me to change gears earlier and not drive to red line.

[STATUS]

remmeber with a 26 if your turn the bearings the crank is toast (most of the time).... they bend like a slinky.

Prevention is far better than cure.

Run an extra litre in the sump and start saving for a build.

[R31Nismoid]

im running hks 25/40 turbos so they are steel wheels. Holy crap didn't think preventative measures would cost that much. How the hell did Nissan build such a good car and F#@k up the oil part. From what you guys are saying from 50 cars that start the track day, an average of 1-2 will die is the norm. Now that sucks. Oh and now i know why my 3 instructors were trying to get me to change gears earlier and not drive to red line.

standard - the motors are relatively fine .

You could really do with better turbo's if you wanted to track

2540's are the black sheep as they make power, but not responsive at all.

But do that once the motor dies.. i mean... if it dies

[fatz]

lol

pull it appart to put restrictors in

do it when it blow, over fill ect

i run a fair whack of oil im ny rb26's never had a problem

and the old 32 has two driver every track day

oh yea reving to 8500 at the track on a stock motor probably isnt the best

[XRATED]

Add on an accusump.... simple.

[duff]

25/40 are what came on the car and i would rather these turbos than the stock ones for sure

[MrStabby]

Random, uneducated thoughts about what could be risky for oil starvation;

- High revs, especially during long sweeping corners

- High grip suspension/tyres (the oil will be sloshed up the side of the sump harder in corners)

- High volume oil pump (more oil out of the sump more quickly)

- Thick oil (will take longer to drain back down)

So if i were you;

- Overfill the oil to the bottom of the top hump on the dipstick

- Dont use R-spec or slick tyres

- Dont rev too high, maybe change at 7000, and short shift where you cant use full power out of corners. This will be more of a problem with laggy turbos that need revs

- Use a good synthetic 0w-40 or 5w-40 rather than a 10W-60...

Also some people say that adding an oil cooler will help with oil starvation - i'd love someone to explain how that works to me.

Why not PM the guys that lost motors and ask what, if anything, they did to stop/resist oil starvation (assuming the motor wasnt lost to through some other reason)

[SiR_RB]

i think oil coolers are used as it adds another litre or so of oil in the system without overfilling it on the dip stick.

[Beer Baron]

oil cooler doesn't really help with oil starvation directly but it helps keep RB26 engines alive on the track. without one a hard driven GTR will heat it's oil well past it's useable temp. then the oil stops lubricating properly, film breaks etc and it becomes very thin. hence engine failure. the extra volume in the system compounds the cooling advantage too as there is physically more in the system but again doesn't really help with the pick-up getting starved during cornering etc. but it's a must have none the less.

[MrStabby]

i think oil coolers are used as it adds another litre or so of oil in the system without overfilling it on the dip stick.

Think about it - that extra oil is not available for the oil pump pickup, because its already been pumped. Coolers make no difference to starvation AFAICT.

[bozodos]

Out of interest, are RB25's prone to oil starvation in these sort of circumstances as well?

[R31Nismoid]

Think about it - that extra oil is not available for the oil pump pickup, because its already been pumped. Coolers make no difference to starvation AFAICT.

2nd'ed.

You need to add TWO litres if the oil cooler sucks up one litre

[GT-RZ]

yea. all RB's. poor design and the sump is too small.

[bozodos]

I would have thought the 4WD sump on the GTS-4, Stagea and GT-R would be big enough for normal sort of hard driving - mine takes 5.1 litres!!

Obviously not in the case of the GT-R at least.

[GT-RZ]

nope. they all take around 5 litres. street driving is fine, the problem is when ur in high revs for a longer duration, oil is in the head and not on the bearings then it's time for new rings if your lucky.

[blk180]

I was one of the GTRs that did the bigend bearing and i have all the mods BAR the oil return from the back of the head.

Mods done

: Larger sump with tomei sump baffles

: Tomei oil restrictors with returns enlarged

: I over filled on the day

I would say Revs and the frist sweeping turn did me in i was holding it in 4th down the straight maybe 8500rpm or so as my 4wd was playing up and getting power done was more wheel spin the grip lol.

But it still gave up the ghost so i say fit it when it breaks.