I Killed My Rb25... Again:(

[NickR33]

rightio then... as some of you are aware I had an engine 'issue' at Sandown last week ... well the motor is almost out again as we are pretty sure its a big end bearing...

it seems that even though my car is pretty stock (stock turbo running 10.5psi) and I run on Azenis (basically street tires) I have managed to starve the bottom end of oil and spin a bearing... sooo just want to send a warning to the RB25 guys who are thinking of tracking their car, DEFINATELY overfill the oil by at least a litre... my oil was filled right up but I neglected to overfill it as I always assumed it was the GTR guys who had to worry

so yeah Nissan did not intend the RB25 to sit high in the rev range whilst throwing it round corners!

The engine is almost out again and I thought I would post what I intend to do to stop this happening again and see if all the gurus think my plan is kosher... most of my research has been SK's oil control thread in FI

the motor has been rebuilt previously after I had destroyed all the piston rings, run it low on oil and spun a bearing (on the street)... the whole thing was reconditioned, crank was fixed up as it was scored, stock rods were retained, Arias pistons 20thou over... water pump was replaced but stock oil pump remained (this may not be performing 100%)

my plan of attack this time is to replace the bearings with some ACL (any recomendations on brand here?)... clean up the crank... install GTR rods (insurance for later on)... install 1mm restrictors in both oil feeds to the head and grind out the oil galleries for better flow... replace oil pump (need guidance here, are there any bolt on solutions)... install oil cooler... bolt it all back together and hope for the best

is there anything I have overlooked? I don't want to go to an aftermarket sump because of the cost... trying to keep the costs low as possible on this one, just want the car to be reliable at the track and to be able to cope with around 250rwkw when I upgrade the turbo.... any help from people doing or have done a 25 rebuild recently is most appreciated

[SXR]

Sorry to hear about your motor.

I would think about changing cranks.....you may have internal cracks.

On the first time did you have grind it or linish it?

[evil_weevil]

Ouch mate not good to hear

In regards to the oil pump - if doing track days/events say once a month - is it worth getting a better oil pump?

What types are out there?

Hope its a speedy recovery mate

Cheers,

Chris

[NickR33]

Sorry to hear about your motor.

I would think about changing cranks.....you may have internal cracks.

On the first time did you have grind it or linish it?

hmm good question, I think it was ground but I will ask... I will definately send it off to get inspected first

[Roy]

Bugger, sorry to read you have hit problems

[paulr33]

sorry to hear nick, hope u sort it out

[NickR33]

thanks guys... haha Roy 'problems' is one way to put it!

[mid life crisis]

THE FIRST THING I WOULD BE DOING IS BAFFLING THE SUMP AS TO KEEP THE OIL AROUND THE PICKUP . USED TO DO THIS WITH EVERY SPEEDWAY MOTOR WE BUILT AND HAD VERY LITTLE TROUBLE

sorry caps opps

[Roy]

Yeh, not a bad idea, But you don thear of too many rwd RB spinning bottom ends. What oil were you using? Any idea of temp at the time you spun the bearing? At what part of the track were you on when th eproblem surfaced? Did you have any misses up until that point?

[R31Nismoid]

Get a 33GTR crank and use that with the rods.

Better off in all respects.

Then give it to Racepace to assemble, and you'll never have a problem with motors again

[NickR33]

Yeh, not a bad idea, But you don thear of too many rwd RB spinning bottom ends. What oil were you using? Any idea of temp at the time you spun the bearing? At what part of the track were you on when th eproblem surfaced? Did you have any misses up until that point?

Using your standard Penrite HPR stuff, 15W I think... oil was 4,000km old and really should have been changed (had done a DECA on that oil)... oil temp was okay, in the high 80's low 90's at the time... no misses car was running great, I was coming out of the 3rd last corner, going under the bridge, high rpms in 3rd gear and it just let go

yep Ash seriously considering that option... I really don't want to have to take it out again

[R31Nismoid]

Yeah, taking it out a 3rd time im sure wont make you happy hehe

[Al]

Hey Nick, i'm building my motor: it's a little different but same principles apply.

Basically doing what SK has listed in the thread you refered to.

Fitting a H.E.(High Energy, circuit type) 8.5L baffled sump and an N1 oil pump.

I am also using GTR race bearings (ACL, i think). The block has to be modified to fit, but the gtr's have groves in the middle of the bearing to improve lubrication to the crank (and possibly rods).

Oil is the blood of your engine, the cost of the sump is cheap insurance and eliminates any possibilty of oil starvation.

Good luck buddy, hope to see the beast back on the road soon.

[R31Nismoid]

The sump is a waste of money.

I'll freely say there is absolutely no point.

If its good for a 350+rwkw GTR to use the stock sump, then its ok for a much slower RWD car.

There is even a RWD car that comes to mind, that TURFED a H.E. sump and went back to a stocker

[Roy]

But are we sure that the rebuilt GTRs in Vic are usign completely std sumps?

Either way, i dont think modified sumps for rwd Skylines is a must.

What would be more of a concern is the Penrite. There was a whole lot wrong a while ago when i picked up my car after a tune/service. The next day the engine let go at PI when only making 210rwkws. The fact that it was using Penrite is another thing i added to the column of "probably didnt help" list.

[Ronin 09]

yes i'm not so sure about the stockness of sumps.

would be worthwhile asking the question to someone who knows... eg benno

[LTHLRB]

id recomend a sump first.. its not always ur oil temp but starving the engine of oil. a trust sump has baffles to control the oil while throwing it around corners. if u dont see much track work and its mostly a street car a sump would b a better solution because it has 1L more oil than standard which in turn will keep the oil cooler.

ACL race series bearings are good but with a good tune and standard nissan bearings it should do the job for the power u have.

with a good tune and good oil u shouldnt have a problem.

cheers Phill

use good oil!! motul turbo light is perfect and its not to bad on the pocket

Edited June 18, 2007 by LTHLRB

[Al]

The sump is a waste of money.

I'll freely say there is absolutely no point.

If its good for a 350+rwkw GTR to use the stock sump, then its ok for a much slower RWD car.

There is even a RWD car that comes to mind, that TURFED a H.E. sump and went back to a stocker

You "freely say" alot of things Ash; many of which alot of people disagree with

[Al]

yes i'm not so sure about the stockness of sumps.

would be worthwhile asking the question to someone who knows... eg benno

Ben is very secretive about his builds, and fair enough, he has invested alot of his time and effort to sort out the common rb26 issues. So i'm not too sure he would give an honest answer, if one at all.

But it's not too hard, or expensive, to fit a Tomei baffle or even make one of his own.

[Al]

ACL race series bearings are good but with a good tune and standard nissan bearings it should do the job for the power u have.

I wouldn't think you would fit race bearing for power, but to accommodate/protect for extended periods of higher reving.

At the end of the day, i would prefer an "overkill" setup, just for piece of mind.