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Hi guys

As i approach the next part of my build i yet again need to ask questions research etc

Im going to slap on my oil pump tomorro and setup the front end of the motor but i have a question about the shimms supplied with the pump , not knowing what the oil pressure will be what is the suggested amount to put in if any? I read a fiew topics in other forums and they say run non and chek and put in as you need but this seems not to practicle since how do pumps like the trust one do this since its in the sump?

Instructions are in jap no mechanic will lend info without getting paid so i ask u guys...

Oil related info on engine

- tomei pump

- 1.1mm restrictor

- head oil drain (spool)

- 8-9 ltr sump ( not purchased yet)

If any other info is needed ask :)

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https://www.sau.com.au/forums/topic/402075-tomei-oil-pump-for-my-gtr/
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Firstly i hope you have a really good crank collar fitted, even the longer snout drive on the R33 GTR cranks can cause issues.

If you rebuilt your engine did you balance the rotating assembly?

What harmonic balancer are you using? Ross or ATI? If not, at least buy a new genuine one. Torque the bolt up to the correct amount as well. 446Nm or for an RB26.

Start with no shims and see what your oil pressure is like when hot.

Ok i have a 33 series 3 gtr so crank is ok it got balanced and i have a ati 500 hp balancer what colar should i use ive never changed or done it before whats the process?

What pressure am i after ?

The factory crank collars tend to be far too small. Too much clearance between it and the pump gear.

Sounds like your engine is built so your stuck with the factory drive. At least its a long nose one though.

Balanced crank is good as is the ATI balancer.

More oil pressure is better to a point. AS A MINIMUM you want 10PSI per 1,000RPM. Oil pressure also depends a lot on what viscosity oil your using.

But lets say its a street car, you have your rev limiter set to 7,500 RPM, when the oil is hot, you would like around 90PSI at around 4,000RPM all the way through to 7,500RPM. Being an RB26 your rev limiter may be higher.

The more oil pressure you have the better (higher pressure around the bearings prolongs bearing life), but the more oil pressure you have the more problems you have trying to get the oil back down to the sump as quick as possible.

Run it without any shims and see what pressure you end up with and then go from there.

It is an external adjustment with a Tomei pump, so you can add shims after if you need more oil pressure. The old rule of thumb for oil pressure is 10psi per 1000rpm. But its cool if it goes higher. So long as its with in 70psi-100psi hot then its fine. If you are revving it high-ish (over 8000rpm) then aim for a higher pressure closer to the 100psi mark.

Almost every other pump has its pressure adjustment inside the engine where you cannot get to it. Hence why it needs to be set right first up. The Tomei pump is a superior design, you can adjust the pressure accordingly whenever you like :)

Im building the motor myself its my first at the moment i have the long motor assembled but the sump is off still and the nose of the crank is still accessable timing gear is off too tomorro im going in to install some of the timing shit eg idler tensioner water pump do u reccomend the nitto rb series collar? Ill buy one now if u suggest

Yes i'm having a Nitto collar fitted to my crank.

However, you need to have a machinist fit it, crank must be removed from engine and then be machined down, then the collar heated and knocked on. Then grub screwed on as well.

Just make sure a good machinist fits it!

Oh if you HAVN'T grub screwd your crank, have this done at the same time. Well worth the $100 to have it done.

Once the collar is fitted and grub screws done, quick re-balance.

If you have not balanced your flywheel and clutch, do this as well, on its own.

Ok explain this grub screw thing coz I put one in each on the side wall on the big ends I got them supplied did not know they were aftermarket????? I just bought a jun collar for $193 delivered rhd jap

gee u didnt have to pay that much 4 a collar but at least u have peace of mind its a real good one. the grub screws go on the counterbalancers of the crank. std cranks have aluminium bungs which can apparently come loose with high hp/rpm. so a machine shop removes these cuts a thread and grub screws them. also the crank can then be flushed out properly through the journals.

edit, but then your crank collar has to be grub screwed also this is seperate :)

Edited by mico

You could have bought an identical collar from me for $70 delivered!

But I really wanted to say forget the head drain but be sure to drill and tap two 20mm holes as high as possible in the sump for breathers (necessary for an RB30 - don't know if they are for a 26 but you can always plug them if you don't v having to pull the motor to add them later) and I would go 1mm on the restrictors (just one on a 26?)with your Tomei pump.

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