Jump to content
SAU Community

Recommended Posts

That looks the same as my rb25 oil pump.

The drive is on the actual crank. I haven't seen a R33 GTR+ crank so I really don't know how it differs.

I assume the motor is now dead? :S

What rev's were being pulled to damage the oil pump?

I heard a loud snap, checked rear view to see if i ran over anything, saw oil pressure wasnt there, shut the engine off, pulled over and waited 1hr for a tow truck to take me home.

I was doin 60km/h, down a hill, maybe 1500-2000rpm at the time when it let go.

Now after looking at this... are ALL crank snouts too short? or is it just when you fit a twin cam oil pump onto the rb30 crank?

Id appreciate it if someone could lay down the short crank snout, crank collars, oil pump problems once and for all so we can add it to the PDF or at least have an article on SAU, after ~2hrs of searching i havent found much info at all.

Link to comment
Share on other sites

The R32, S1 R33 GTS-T's & R32 GTR's all have the same small crank engagement.

I've got a couple of pics of an apparently R34 GTR crank but I've since found the same pic and it was named a R33 crank with the Jun adaptor attached so I really don't know what the pic is of. :)

I need pics. I can't remember if I took any of the rb20det when I had it out, I'll have to scrounge around.

Link to comment
Share on other sites

I've dug through some pics and found a pic of the rb30e crank drive and the rb25det oil pump crank drive.

Looking at the RB25DET oil pump really makes me wonder if the oil pumps differ at all from the newer ones.

Could it be that only the crank drive differs?

Edited by Cubes
Link to comment
Share on other sites

I've just found some other pics.

RB30e oil pump internals.. note the small crank engagement.

And this is a suspect pic... I'm unsure if its a R33 GTR crank or another earlier crank with a Jun adaptor.

Link to comment
Share on other sites

Skyrine Dave,

Looking at your stuffed oil pump pic.

I think whats happened is its first cracked where the crank drive touches the oil pump, then jammed then stripped the drive.

The crank and oil pump is not a really tight fit, as a result the direction of rotation will have the crank drive place a greater load towards the front of its direction (clockwise). .if that makes sense.. You can see the crack begins from this greater load point.

Have a look at this pic.. You can see where the crank drive has previously wore the oil pump gear slightly.. The mark towards the inner of the engagement looks the exact spot where yours cracked.

You didn't miss a gear any time prior by any chance OR using a R31/VL/VLT Harmonic balancer?

Edited by Cubes
Link to comment
Share on other sites

Nah didnt miss a gear. I am starting to think harmonics may have been the key factor in actually cracking the gear in the first place.

Im using an RB20DET balancer from an R32. Which ive noticed has a nice chunk of metal taken out of it, which wasnt previously like that. Im considering taking it in for a re-tune once its bolted back together and lowering the rev limit to 7000rpm, was previously 7500rpm and it can hit that limit in the blink of an eye given the opportunity to spin

Link to comment
Share on other sites

That is scary... For me... :P

The N1 gears apparently run a tougher gear, I remember some one did a metal hardness test on the N1 and non N1 quite a while back and that was the result. N1 = harder. BUT N1 does run higher oil pressure so that in its self places more strain on the crank drive. I might do a little looking in to a crank collar, its not hard to fit especially if one is pulling bits off to replace a headgasket and oil restrictors in the future.

Totally unrelated - Where does yours make its peak power?

Link to comment
Share on other sites

Would be interesting to find out how the collar is installed and if its an at home or workshop only job!

peak power is when ever the rev limiter kicks in... when it was at the dyno they told me they took it to 8000rpm and the power was still climbing. this is after i said 7500rpm only.

maybe an ATI balancer is on the cards :P

Link to comment
Share on other sites

WTF... Power still climbing at 8000rpm?!? :D

What sort of cams and exhaust manifold/turbine housing have you got on that thing?!?

Sky30 with his stock exh. manifold must be really sucking the rpm's out of it. His makes its peak of ~312rwkw at ~5800rpm.

With regards to the collar... I remember someone stating its held in place by a little screw of some sort.. That makes me nervous just in its self, especially knowing the vibrations that travel through the crank. :P

Edited by Cubes
Link to comment
Share on other sites

Yeah who knows what they did to the car.

I just looked at the dyno sheet. No RPM just KPH :D But it seems to reach peak power at ~160km/h in 4th..

I am with you Joel, Im wondering if the only thing that varies between the RB cranks is the oil pump drive, rather than the actual oil pump itself.

Id be interested to see if the R32 RB26 crank has a small crank drive or if it completely engages its oil pump drive... hmm

Link to comment
Share on other sites

I've found the origin of the pic I posted earlier

http://rbmotoring.com/gallery/album36/abf?full=1

Its apparently an R32 GTR Crank with the oil pump drive collar to widen the area of drive. There's a nice 1024x768 pic. From what I understand one must first machine off the origional small crank drive then fit up the jun item.

After a bit of looking in to it I am 99% sure that all the pumps are the same, its only the drive collar that differs. I could be wrong.

Edited by Cubes
Link to comment
Share on other sites

Google is my friend. :)

R32 GTST/GTR and R33 Series 1 GTST's have the same short oil pump drive.

R33 Series 2 GTST's have the long drive.

All R33 and R34 GTR's have the long drive.

RB30ET's have the short drive and don't suffer the same problems, BUT they do have a different designed gear, the gear's aren't loaded up as much as the pumps run less pressure and flow less oil + they don't rev as hard. :)

Now trying to find one for a decent price. I remember Nengun wanted $600 for one.. Or something around that mark anyhow.

Edited by Cubes
Link to comment
Share on other sites

peak power is when ever the rev limiter kicks in... when it was at the dyno they told me they took it to 8000rpm and the power was still climbing. this is after i said 7500rpm only.

Nice power your making dave, Which head are you using??

What Cams and exhaust manifold?

What car have you got your engine in, what RPM is 160km/h in 4th gear?

Link to comment
Share on other sites

Nice power your making dave, Which head are you using??

What Cams and exhaust manifold?

What car have you got your engine in, what RPM is 160km/h in 4th gear?

Rb25det head, stock cams, custom work of art exh manifold made by a mate. No idea on RPM, tacho wasnt wired up by the workshop and i havent had the time to find out for myself.

My rb20det 5psd used to show as 1:1 in 3rd gear!

This is an an HR31 passage, R200 LSD rear end.. i dont know how to work out ratios etc

Link to comment
Share on other sites

i have the tomei pon cams, so they are 256 degree duration..

bought them before deciding on going for the 3L..

have been thinking of running 264 degree's but still con entirely sure they would work ok on the hydrolic lifters..

i have no problem with getting the "machining" done to clear the lobes, wont have to do as much prep as Gary as the head will already be off the engine.

would solid lifters be better with 264 deg cams? or if im not revving past 7500rpm the hydrolic ones be up to the challenge?  is this the same with the valve springs? trying to keep the costs down as far as i can :P

you thinking of selling the Poncams ?

Link to comment
Share on other sites

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



×
×
  • Create New...