Rb26 Oil Pump Choices

[bubba]

VERY keen to see how this turns out.

[NITTO]

A spline drive collar and inner oil pump gear would be ideal... I chipped in for a set for manufacture by one of the guys on the forum last year, unfortunately it didn't happen....

I firmly believe, an Aussie company would make a killing by manufacturing a spline drive collar and inner gear oil pump set... Especially with a well proven product like Nitto... hint hint.

J.

Have been carrying out field testing on several new designs for a while now. Will let you guys know once final prototype testing is completed and new design is approved.

Aim is to provide end users an option to run the OEM style drive on our pumps or install updated design drive collar on the crankshaft and we will supply our pump with inner gear machined to suit the updated drive suface on the collar.

[bubba]

Have been carrying out field testing on several new designs for a while now. Will let you guys know once final prototype testing is completed and new design is approved.

Aim is to provide end users an option to run the OEM style drive on our pumps or install updated design drive collar on the crankshaft and we will supply our pump with inner gear machined to suit the updated drive suface on the collar.

What about a set of gears to suit OEM RB26 and N1 pumps?

[Beer Baron]

I have already got design drawings for the N1 profile as I make the billet gearsets for the factory pumps but I agree that the spline idea is worth trying. I have a very reputable wire cutter that can cut any drawing you want to absolute perfection (as a spline will need to be wire cut, not CNC machined I believe)

If anyone wants to have a crack at it and talk to the wire cutter for quotes, I would be happy to sell the drawings already digitised and ready to go in the correct format. I say sell as I had to pay a fair bit of money in set up fees and digitising.

Shane (I think) still has the drawings for spline drive too but they may still be at the old dodgey machinist that he was going through.

I can also lend a doner collar made by our machinist.

I just lack the time and motivation after trying to sell the normal billet gears. They don't sell like hotcakes, I can tell you that

yep, have to be wire cut.

if shane has the designs I have a buyer who will pay for them and he has the motivation and the money to see this project through and get them made in aus. if shane or whoever wants to contact me I will get it done.

[Beer Baron]

Well if it help here is a photo (from Serge at NextGen Photography - he does awesome work) and a data log. Trim puckering moment at about 176 seconds when the thing spat sideways on the exit of the chicane at Collie. Which may or may not have been shortly after Serges photo.

For what it is worth none of the options I listed teamed a high volume pump with a stock sump. For the very reasons teh Baron explained.

The hard part is, as ever, deciding how much is enough. There is no data and can be none on how much flow is sufficient. For what it is worth I think I will be going a Tomei pump & larger sump. Just hope the people at Visa understand.

yeah I think tomei pump, crank with collar and big sump along with enlarged oil returns and an oil feed restrictor (i'd go 1.2 or 1.1mm with a tomei pump) is probably a good solution for your car. and I knew there was no way you'd consider an upgraded pump on a stock sump. your name alone tells me you are far too smart. lol. but it was mentioned so I just responded to that.

[Beer Baron]

Does anyone know conclusively what causes the pumps to fail, or is it mostly guesswork and hearsay?

The only possibility that comes to mind is that if the crank is wobbling side to side (and up and down) at the pump end, that at a certain point in its rotation the crank drive collar might lean (hammer)on the inner gear with sufficient force that it is striking the outer gear which is hard up against the pump housing. What starts as a hammering eventually creates a crack in the inner gear.

So you’d have to be pretty unlucky to have one fail, but what would make the probability that it could happen worse would be loose main bearing clearances combined with a poor balance on the crank, flywheel/clutch and harmonic balancer.

To me this also makes sense why the Tomei pumps tend to survive a little better. It wont just be the metalurgy, but also the splined drive in the pump gear allows for a little more movement. It would be interesting to see how tightly the drive spline on a 2JZ holds onto the crank. Im guessing there is a fair amount of play, enough to tolerate ~4 thou of movement.

Im really just guessing though...

mostly guesswork and hearsay to be honest. including on my part. though I ahve looked and plenty of broken pumps and considered what those engines were doing, what power they made, who built them, did they have collar etc.

crank whip is part of it. I mean RB26 crank is a long I6 crank with all the inherent harmonics problems and balance problems. it's rare (but not unheard of) to see pump failures amongst guys with good balancers and well balanced rotating assemblies.

what you described is the common failure. pump drive hammering the inner gear which pushes against the outer gear hard against the case causing one or both to crack. there are usually witness marks on the collar and the inner gear.

rev limiter abuse comes into it too.

it's been a while since I pulled the tomei pump apart but from memory the inner half of the inner gear is a very tight fit on the outer part of the inner gear. they are splined but not much play there if any.

poor balancer, poor balancing of the engine, poor (none) balancing of the flywheel and clutch and large bearing clearances definitely add to the failures.

a 2JZ style arrangement with a coolar that fits the crank with the spline drive on the outer to drive a splined inner gear is definitely the way forward.

[bigmikespec]

yep, have to be wire cut.

if shane has the designs I have a buyer who will pay for them and he has the motivation and the money to see this project through and get them made in aus. if shane or whoever wants to contact me I will get it done.

It is the best way but it is expensive; the tighter the tolerance, slower the cut, more $$$.

Seems like someone has already done it but the offer is still there. If someone has a set of old gears and a crank or a crank collar I can do the design and also FEA (for s**ts and giggles).

[Beer Baron]

well I have a guy here in syd who 100% wants to go ahead and have these made. neither of us are confident enough in our CAD skills though so we need a design. he has access to the right materials and a machine shop that can wire cut the gears etc. and plenty of motivation to do it.

[dato$2nv]

i had a n1 pump fail on , as far as ive researched it seems a n1 pump is just a standard pump with a better spring in it ?

i now run a nitto pump with a oil restrictor, i chose nitto as its australian and just as good as jun so might aswell keep the money local...

[djr81]

i had a n1 pump fail on , as far as ive researched it seems a n1 pump is just a standard pump with a better spring in it ?

That isnt right.

Here is a photo of an N1 pump rotor assembly (on the left) and a stock one (right). Thanks to SIR R32 for the photo to clear it up.

Of note:

N1 internal gear as 11 teeth, stock has one more.

The outer diameter of the outer rotor on the N1 pump is SMALLER than the stock pump.

The tooth profile (particularly of the outer rotor) is markedly different between the two.

Not shown on the photo but when pulled apart the casings are also markedly different.

[dato$2nv]

i believe they are different , but since failing and spinnign bearigns which cost me $$ i wouldnt trust one with 350rwkw again

[SIR-032]

That isnt right.

Here is a photo of an N1 pump rotor assembly (on the left) and a stock one (right). Thanks to SIR R32 for the photo to clear it up.

Of note:

N1 internal gear as 11 teeth, stock has one more.

The outer diameter of the outer rotor on the N1 pump is SMALLER than the stock pump.

The tooth profile (particularly of the outer rotor) is markedly different between the two.

Not shown on the photo but when pulled apart the casings are also markedly different.

Your welcome djr81

Billet gears in the N1 oil pump go along way to solve the problem of gear sets failing

any pump with billet gears is a great solution Really

With TOMEI addressing crank to gear clearance issues also

Happy RB26ing

Pic attahced Billet gear installed Stock gear to the left

[DVS JEZ]

3posts up. The pic of the stock vs n1 gears. No wonder the n1 outer gear keeps breaking. There is not enough meat on it.

[djr81]

Attached is the info sheet that comes with the Tomei pump. (I bought one).

Couple quesries if anyone can help with the translation.

1. There are three tiny disc shaped shims and a washer(In the box on page 1). Cant make out from the manual where these go other than under the external bolt shown on the pump on p3. Is that correct?

2. Basically what is written on the table on page three?

[XRATED]

Have been carrying out field testing on several new designs for a while now. Will let you guys know once final prototype testing is completed and new design is approved.

Aim is to provide end users an option to run the OEM style drive on our pumps or install updated design drive collar on the crankshaft and we will supply our pump with inner gear machined to suit the updated drive suface on the collar.

I'm realy pleased there is some development going into the drive arrangment!! and that it's an Aussie crew that are doing it.

yep, have to be wire cut.

if shane has the designs I have a buyer who will pay for them and he has the motivation and the money to see this project through and get them made in aus. if shane or whoever wants to contact me I will get it done.

I'd still love to see shanes design refined and manufactured.

I can't see any other way to get a more reliable/robust pump and drive arrangment than a splined drive similar to the 2J design.. we just have to get the tooth profiles rright!!!

Bring it on- the market is here!

[GTRNUR]

I thought i'd revive an old thread to see if Nitto has made any developements that they would care to share.

While meandering around the internet I stumbled across this on the BC website for the 2JZ as an upgrade.

http://www.briancrower.com/makes/toyota/2jzgte_misc.shtml

I cant see why one of these couldnt be fitted to an RB crank. This is 1/2 the battle won right there.

[Beer Baron]

Attached is the info sheet that comes with the Tomei pump. (I bought one).

Couple quesries if anyone can help with the translation.

1. There are three tiny disc shaped shims and a washer(In the box on page 1). Cant make out from the manual where these go other than under the external bolt shown on the pump on p3. Is that correct?

2. Basically what is written on the table on page three?

1, yep follow the pic. They are used to shim up the pressure valve.

2, the last 3 columns show pressure at rpm points using 1 shim 2 shims or 3 shims. First column is with the weak spring installed, second is both spring then both springs with shims.

[Beer Baron]

Actually I might have the springs ass backwards but the last 3 columns are 1,2or 3 shims.

[XRATED]

I thought i'd revive an old thread to see if Nitto has made any developements that they would care to share.

While meandering around the internet I stumbled across this on the BC website for the 2JZ as an upgrade.

I cant see why one of these couldnt be fitted to an RB crank. This is 1/2 the battle won right there.

I've been saying it.. been saying it for years....

I just don't have the time, expertice of cash to develop it. I do hope that nitto or another aussie company get onto it and produce a quality, spline drive rb oil pump and drive soon. I've got an engine to build damn it!!!

[NITTO]

Hi guys.

Finishing off some finial revisions to the spline contours and re-testing at present. Should be good to go very soon.