Rb26/30 Oil Pan & Head Drain For Street Use

[Shoota_77]

Every company that makes the collars has their own method and measurements that they're working off so will all vary to a degree. It only needs to be a few thou different to make the difference between being an interference fit and "loose".

In an ideal world you would take your intended pump drive inner ring to the machinist and have him match the new crank collar to the inner ring to be a perfect fit. Even to the point of having to slightly heat the oil pump inner ring when re-installing the pump it so it slides on. This would potentially cause issues though when time came to remove the pump as it could get pretty well locked onto the crank collar once a bit of rust formed. Theoretically you shouldn't have to pull it apart too often though.

That's entirely my own logic so feel free to rebuff!

[SiR_RB]

I've started my rb30/26 build (well sorta) and I'm going stock (new) 26 oil pump but with reimax billet oil pump gears/nitto crank collar

90% street driven we don't see the need for anything more

[coopeR32]

is there a difference in the N1 pump and the std pump if you change the gears to billet items??

[Shoota_77]

Yes. The N1 pump has smaller gears than the standard pump.

I can't recall the actual measurements but it's about 5mm or so difference.

You need to order the right gears for the pump you have in other words.

[r33_racer]

Spend your money on a good set of pistons with good rings that will actually seal...The RB oiling problem is 90% excessive crankcase pressure (too much blow by) and 10% too much oil flow to the head. You need to fix the problem at the heart of it all!

Putting on extra crankcase breathers is only another band aid fix. Which does work fine though. If your engine is already built or bought, then adding the appropriate breathers is your only real choice.

[XKLABA]

Spend your money on a good set of pistons with good rings that will actually seal...The RB oiling problem is 90% excessive crankcase pressure (too much blow by) and 10% too much oil flow to the head. You need to fix the problem at the heart of it all!

Putting on extra crankcase breathers is only another band aid fix. Which does work fine though. If your engine is already built or bought, then adding the appropriate breathers is your only real choice.

exactly, the problem isn't getting the oil to the sump it's letting the air out and in an ideal world piston rings that seal perfectly would be lovely but not everyone can afford them, so crank case/sump breathers are a good solution/alternative

given the design of the head (26 anyway) the "rear head drain " is more just a breather and even though some oil does go down it the air it releases from the bottom end is its main benefit

as Shoota_77 has said the gears in the stock pump are bigger and IMO would be the choice of OEM pumps if you are going to change the gears to the Reimax ones and shim it for a bit more pressure

[SiR_RB]

Can anyone confirm if the cp piston kits come with optional upgraded "high boost" piston rings??

When my mate did his rebuild they asked if he wanted the standard rings or better ones for extra $150 or so

I cannot find much info on these different rings