Rb26 Oil Pump Choices

[GTRNUR]

cany find real info mation on this damn round about of a way site you wanna know my experience PM me all ill tell you REAL life engine touching blowing up fixing INFO

My head hurts when I try to read this!

On topic though...

The other benefit worth considering is that it takes longer to heat up a larger oil capacity. This is useful for sprints where your at consistantly high rpm and not necessarily getting a lot of airflow. Its been my experience that cooling systems dont work well until your above 80km/h (and in a tall gear, not in 2nd and 7000+ RPM, at full load). Below 80 your cooling is predominatly fan derived.

Im with Steveo with the higher flow and smaller restrictor option too. I like the idea that my bearings area getting plenty of oil flow to keep them cool. I also like that 7 litres of oil stays cleaner for longer compared to a smaller pump.

[bodge]

I know of 2 guys both using n1 pumps and over filled there sumps by 1 litre and still managed to smash there pumps. If money is not a concern I would go for the tomei pump for peace of mind as it has been proven that they can take alot more punishment and being based on a 2jz style of pump you don't hear of them having any problems.

[R31Nismoid]

^ The way that is worded - it comes across the wrong way. So i hope it's just wording as overfilling the sump has nothing to do with breaking a pump. They are totally independant of one another.

[bodge]

I'm not saying that over filling the sump caused the pumps to fail. I just thought l would mention it as it was brought up in this discussion.

[The Dan]

Most of the failed N1 pumps I have seen are accompanied by an equally failed harmonic balancer. At 8000rpm, if you have even the slightest harmonic imbalance, you are going to hammer the living f**k out of that gear. They get larger, they cease to fit in the round hole they are designed to turn in and they start to grab, then they crack or break.

I have seen many people successfully run N1 pumps and standard capacity sumps at the track and not have a problem. I have seen guys with Tomei pumps at the track have problems. It works both ways and it's not always about having the absolute most oil flow you can possibly imagine and all your problems will just waft away. The fact is, the N1 pump flows enough to cope with any amateur type racing events, but is your oil up to the task?

If you are going to run the N1 pump, make sure you are using an extremely high pressure resistant oil that has a film strength higher than any other oil on the market - Royal Purple

It never hurts to have a larger sump capacity and it never hurts to have more flow, at the end of the day, fuel and oil are two of the most important things you need. Who really cares about cost? Another engine rebuild is going to cost you a frig load more.

Another fact is that the materials used to make the Nitto and Tomei pumps are much stronger than the material used to make the N1. They WILL handle more punishment and not break. They have a longer fatigue life due to the material they are made from.

It's the same as the forged conrod argumement - yes the factory rod can handle a shit tonne of hp, no it will not last forever. The fatigue life of a forged rod is much much much longer than the factory rod, and for $600-$800 for a set, why would you stuff around putting old (possibly tired) parts back into your new engine?

If it were me, and I was going to spend 2-3 days a year at the track and 80% of the time it will be a daily, I would leave the sump and put on the N1 pump. If I was going to be spending a day every 4-6 weeks at the track, I would invest the money into a Nitto item. They aren't that expensive and will take a hammering for years

[The Dan]

and +1 on overfilling the sump slightly (0.5 - 1L) at track events. But make sure you have a good catch can setup and check it every 5 laps or so if you can. You'll get to know what your car can handle once you have spent some time out and about

[The Dan]

Yours are working?

We thought they were still broken...

Yes, mine are working

[SIR-032]

Obviously with added oil/larger sump the oil temps and similar are beneficial to the cause depending on use.

Snowman & Scotsman both ran stock sump'd GTR's for 2-3 years no problems in that department. Motors were stock too and eventually the died but that's what happens @ 330-360rwkw over a hard life. Since then they've both used N1 pumps, as have pretty much all Vic cars. Not one has broken a pump yet. Most motors hand together fine as well (failures are not pump related).

So if you are a bit worried then swap out the gearset. They aren't too expensive and if you get piece of mind then that's covered off.

Comes down to cost really:

Option 1 - 1500 Closer to $750 if savvy Billet gears from JPC.com.au $350 can be used

Option 1.5 - 2300

Option 2 - 3200-3500

I'd also suggest if you are going to go all out on a pump, that you use the Tomei one. It's the only one that utilises a different gearset arrangement similar to that of the 2JZ (never hear of them breaking pumps). It's something I've never really worked out why the other aftermarket pump makers don't use the Tomei/2J style as for a bolt-on pump, it's the way to go.

Thank you R31 Nismoid for the answer above its a very valuable and credable answer

[R31Nismoid]

Have trouble finding your test results?

[The Dan]

Have trouble finding your test results?

He hasn't looked under his ego yet. Get a couple of fellas to help him lift it

[SIR-032]

WOFTAE

[Supa Steve]

I would invest the money into a Nitto item.

Well said mate. The Nitto will save you the additional expense of having to pull your engine later when the other pump dies. Its the only pump on the market that has not suffered gear failure and each pump is assembled/clearanced checked by the engineer who designed it not some monkey on an assembly line.

[Deano 1]

you can get a tomei pump out of japan for freakin 1400bux these days, why would you even waste the time on a N1, i mean, you have already spent 6-9k on parts, machining costs, the time pulling it all out, whats the big deal with the extra bit of coin. its not really that much when you think of it, and when it comes down to it, its the rb's weakest link, so why not just put down alil more cash for peace of mind

[ACTIVE-LSD]

Most of the failed N1 pumps I have seen are accompanied by an equally failed harmonic balancer. At 8000rpm, if you have even the slightest harmonic imbalance, you are going to hammer the living f**k out of that gear. They get larger, they cease to fit in the round hole they are designed to turn in and they start to grab, then they crack or break.

This man speaks the truth.

[DCIEVE]

I know you explicity excluded the dry sump option but it's worth considering an external oil pump with wet sump. Cost effective, and you can avoid the ^^ guys getting emotional over your oil pump choice.

People just spout a lot of what workshops feed them without knowing any better.

This made me laugh.

[XRATED]

Nitto pump and collar, tomei sump baffles and an accusump... would have to be the best set up for the money and ease of fittment....

Otherwise, add a sump extension with pickup.

I wouldn't piss about with an N1 pump on a built engine... Saying that, I have an N1 pump (with no collar) on my thrasher rb25 and have had no problems yet- I do have an ATI ballencer though.

I'm not a massive fan of external oil pumps... the only thing that stops total failure is a thin little belt, with little or no guard...

J.

[djr81]

Pharkk, this turned into a pile of less than helpful vitriol.

The point of the thread was to get some determination on the relative merits of flow rates & sump volumes not to get all the monkeys chucking sh!t at each other.

I don’t want the worlds greatest anything for the sake of having it. It’s like having the worlds hardest clutch which will last forever but destroy three gearboxes during its life. Useless. The point is to get a well balanced set up that works harmoniously over the life of the motor which will, eventually, end up dead. Like they all do.

So far to the best of my understanding:

A stock pump will flow 47litres/minute at 6000rpm.

Various aftermarket pumps have claims to have greater flow rates.

The Tomei pump claims to be 20% higher in volume. To be honest I am not that enamoured with the three piece design.

The Jun pump is claimed to be 25% higher in volume.

The Nitto pump (going on their published figures) is 40% over stock however their number for the standard pump flow rate is lower than the one quoted everywhere else.

The downside of a higher flow rate is the need to have a much bigger sump volume, the knock on effects to the head in terms of getting rid of the oil, the pumping losses, the longer period needed to get the greater volume of oil up to a decent temperature.

The upside is it may give you better bearing life longer assuming you don’t get pump cavitation issues.

Oh and lastly there is nothing wrong with sintered metal. It is just a process used to form steel. Hell BMW used to use it for conrods.

Anyway if anyone can help out by way of confirming the Nitto Flow rates I would be grateful.

[GTRNUR]

Do you mean this data from the website:

http://www.nitto.com.au/products/oilpump-RB.html?category=engineblock

Jun pump data is here:

http://www.rhdjapan.com/jun-high-flow-oil-pump-rb26dett-rb20det-rb25det-16702

Tomei information seems to be all over the place.

Data varies from 56-57 lt/min at 6000 or 7000 rpm depending on what supplier website your looking at.

Or were you chasing actual test data performed by an independant?

[djr81]

Do you mean this data from the website:

http://www.nitto.com.au/products/oilpump-RB.html?category=engineblock

Jun pump data is here:

http://www.rhdjapan.com/jun-high-flow-oil-pump-rb26dett-rb20det-rb25det-16702

Tomei information seems to be all over the place.

Data varies from 56-57 lt/min at 6000 or 7000 rpm depending on what supplier website your looking at.

Or were you chasing actual test data performed by an independant?

The data for Tomei was on volume 22 of new release information from Tomei in Seppoland. Put the flow rate for a stocker at 6000rpm at 47L/min & the Tomei pump at 56L/min.

I wasnt necessarilly looking for independent data just confirmation or otherwise of the Nitto flow rates as the listings they use for stock pumps is at a variance to everyone elses.

Edited March 28, 2011 by djr81

[Beer Baron]

I'd also suggest if you are going to go all out on a pump, that you use the Tomei one. It's the only one that utilises a different gearset arrangement similar to that of the 2JZ (never hear of them breaking pumps). It's something I've never really worked out why the other aftermarket pump makers don't use the Tomei/2J style as for a bolt-on pump, it's the way to go.

I wouldn't say the tomei pump uses a gear arrangement similar to the 2JZ style pump? 2jZ pump has a splined gear on the crank, driving the oil pump gear. the tomei pump as a 2 piece inner gear but it still uses the same 2 small flats to drive the pump gear just like any other 26 pump which is the weak point. the gears 'teeth' are slightly different but they are still a gerotor type pump just with much bigger gears with a more suitable material. they are unique in the 2 piece inner gear set-up but still no where near as good as a 2JZ pump. the best option for RB26 is still getting a set of splined gears made up with the inner gear permanently fixed to the crank.