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I've just started my RB26/30 build and i'm looking for advice if its worthwhile enlarging the sump and adding the rear head drain.

The engine is primarily a street engine with very occasional 1/4 mile and track use. I plan to limit the revs to 8250-8500rpm. I already have sump baffles, oil restrictor and a N1 oil pump, and a large oil cooler. I was going to add the sump and head drain but now i think the money could be best spent on other things.....HELP

For the $300 or thereabouts the rear head drain will cost why not? If that was the one thing that prevented your engine spinning a bearing would the $300 be well spent? Shit yes!

With the sump, cheapest you'll get out of it is about $800 for a "proper" extension. Again, a small price to pay compared to the price of rebuilding an engine!

Preventative measures (as opposed to performance boosting mods) are a bit like car insurance, you hope to never have to use it but FK you're glad you had it when shit turns bad!

Money spent on oil system is never wasted. I smashed my N1 pump first time I drifted my RB30/26.

I made my own head drain from 1inch bsb brass pipe fittings (local hardware store, just needed to borrow a tap to thread the head) and 1inch ID red oil line. And upgraded to a Tomei pump (removed one spring to get pressure back to normalish for street). Welded a return into the home made sump and never had another oil warning light again.

Pretty much, everyone ops to go the tomei, greddy, nitto pumps for stronger materials that are used while building these pumps which are stronger then the n1 pumps that are always breaking, on idle and under heavy loads,

I went straight to a nitto pump as I didn't wanna risk breaking a n1 pump and rebuilding my motor again

N1 pumps don't just 'break', more than enough info on the pages of this forum to work that out.

I've run them for 7 years on 3 motors, never broken one and i bash the limiters in them without fear.

Mine "just broke" so I disagree.

And I NEVER limiter bash. My engine had only done about 15,000kms with that pump in it before it went. It had never been on a track and only the odd caning (so I'm told!).

You obviously got lucky. There is some sort of issue with them be it the quality of the material or a flaw in the casting that makes them weak.

There's no way I'd risk a standard N1 pump again, it's not worth it. This time I've gone N1 pump with Reimax gears so fingers crossed......

Mine "just broke" so I disagree.

And I NEVER limiter bash. My engine had only done about 15,000kms with that pump in it before it went. It had never been on a track and only the odd caning (so I'm told!).

You obviously got lucky. There is some sort of issue with them be it the quality of the material or a flaw in the casting that makes them weak.

There's no way I'd risk a standard N1 pump again, it's not worth it. This time I've gone N1 pump with Reimax gears so fingers crossed......

(so you were told), that sums that up - you don't even know!

I didn't get lucky, 60,000kms over the 3 motors says so.

And then what about the rest of the motor? Did you have it checked or just blame the pump?

Was properly balanced? Crank snout and engagement 100%?

Sounds like you don't know that either - so how you can say it "just broke" is... interesting. :)

Ok legend, while there is validity in some of what you say, you need to learn that just becase something hasn't happened to you, doesn't mean it doesn't happen! Whenever someone theorises an issue you have a tendency to ridicule them because "I've..never broken one" etc, etc.

The engine in my car was already built so no, I don't know exactly what was done. It was built by a reputable engine builder/tuner in Brisbane so I can only presume it was done correctly.

I also like how you make your own legendary presumptions- "And then what about the rest of the motor? Did you have it checked or just blame the pump?

Was properly balanced? Crank snout and engagement 100%?

Sounds like you don't know that either - so how you can say it "just broke" is... interesting."

I could go on but it seems it would be a waste of time. You're the "most viewed admin of all time" so clearly the oracle of the RB. :action-smiley-069:

The problem is the harmonics of the stock 30 crank during fast changing from low to high revs, a billet crank is supposed to be better and will take more revs without trying to lunch the pump.

From what I understand a stock balanced crank will be fine with a Tomei pump up to around 7500rpm on a fast reving motor, over 7500 is possible but you are getting over the happy zone, apparently a billet crank can take alot more abuse, how much I dont know but Ive "heard" of 30's being reved to around 10 with one, fact or fiction, I dont know.

I have a 25/30 with a Tomei pump, limited to 7500, I shift at around 7200 though as this keeps me in the sweet torque range and limits the abuse, I donot race for sheep stations so reving beyond that on a stock (albeit balanced) crank is something that does not interest me.

Ok legend, while there is validity in some of what you say, you need to learn that just becase something hasn't happened to you, doesn't mean it doesn't happen! Whenever someone theorises an issue you have a tendency to ridicule them because "I've..never broken one" etc, etc.

The engine in my car was already built so no, I don't know exactly what was done. It was built by a reputable engine builder/tuner in Brisbane so I can only presume it was done correctly.

I also like how you make your own legendary presumptions- "And then what about the rest of the motor? Did you have it checked or just blame the pump?

Was properly balanced? Crank snout and engagement 100%?

Sounds like you don't know that either - so how you can say it "just broke" is... interesting."

I could go on but it seems it would be a waste of time. You're the "most viewed admin of all time" so clearly the oracle of the RB. :action-smiley-069:

Of course there is validity - I wouldn't be saying it if it wasn't there.

Because a pump fails - does not mean it's the actual pumps fault. Think a bit bigger than what you see before you. It's like saying it's a tyres fault for blowing out, but the actual cause was a nail that deflated it, leading to a blow out.

Given you have no idea of the motor build and it's treatment before you got it, sounds like you didn't have it properly inspected afterwards... And as a result cant confirm with any reasonable certainty there is nothing else at play here - you cannot for a second say it's exclusively the pumps fault. The entire design is flawed, hence the Tomei is the "best" solution on a budget... EVen then you can even kill a Tomei pump if you try hard enough or the build overall is poor (users have here before).

Yes to the bigger sump. There is no evidence that the "head drain" actually does anything. If you are still at the building stage drill out and relieve the oil returns and drill and tap one or more holes as high as possible for sump breathers (running to a catch can, not the head. 8,500 is a lot for an RB30 - they can be made to rev to 10,000 but even at 8500 you will need a quality damper and everything well blueprinted and balanced.

N1 pumps don't just 'break', more than enough info on the pages of this forum to work that out.

I've run them for 7 years on 3 motors, never broken one and i bash the limiters in them without fear.

Have you looked at the inside of one?

Compare it to the inside of a brand name upgrade... its very easy to see why they "Just break."

When an engine that normaly rev's underload from 3000 to 7000 rpm in a few seconds suddenly does it in one second but still moves the same thickness and volume of oil with the same thin cogs that a stock oil pump has (N1 or not). Having the right oil restrictions to the head is always a very important thing and enlarging oil return paths is definatly going to lessen the requirement of a head oil drain.... However if you look at the budgetless big race RB's in Japan you'll see many combos of oil drain and even bigger pumping systems. I'm yet to see a pro car with a stock or N1 pump.

This is a street engine, its not going to be a 1000hp pro car. I have read that running a crank case evac system is more benifical than a head drain ( which seems to be fashionable these days ). I understand that N1 pumps are a O.E mass cast item but if the weak point is the gears then a crank collar and billet gears should fix or lesson the chance of breakage. i will also drill tha pan to allow oil to drain back to the pick up area

Crank collar and billet gears will definately help, mandatory as your car is a 32 with no doubt a short snout crank drive.

I would highly recommend getting the collar custom made or at least try to get one that is matched to your pump. Every 26 crank snout I have seen has wear on the leading and trailing edge of the drive suggesting that there is clearance between the snout and the pump drive. No doubt with the harmonics causing a "rattling effect" of the pump on the drive this speeds up the wear on both the drive and the pump.

interesting shoota_77 i was thinking all off the shelf parts are the same, but having one machined to suit my specific parts makes sense. Do you have any recomendations on how to use? i'm located in W.A but i can freight my parts through work if needed.

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