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For both above, I believe the block mount squirters release oil that should go to the bearings, and as much as I know the amount is not enough to make a big deffernce it's still oil released to put oil on something that already has plenty getting put on it, there is enough oil getting thrown from the big ends to coat everything with oil anyway

FFS if they needed to be there dont you think they would wither be there or there would be threads on here littered with people who have bought nitto rods and have then had engine failures.

I told you they are there to squirt a little oil at the piston on the oppoaite side to the block oil squirters to give more even cooling. Its only a small amount of oil and doesnt make a huge difference. Plenty of people running nitto roda and spool rods with no issues

They do however have the half moon slots in the conrod side faces to direct oil up and around. The argo rods I mean.

If you want to improve your Nitto rods, just get your machinist to cut the slots into the rod faces, its not very hard to do. Any chump with a mill and ball nose cutter can do it.

fat32gtr - Our RB26 rods do not run the oil squirter gallery from the big end like our RB30 rods do. We only use this feature on our rods where there are no oil squirters in the block for reasons mostly related to oil pressure. There is no need when the oil squirters in the block are already lubricating the pin area, cylinder bore and cooling the piston crown.

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Its not needed. The majority of aftermarket rods don't even have a feed to the pin bush.

The rod itself has more surface area than the OEM rods and flicks oil up off its surface. Its meant to spray into the piston to lubricate the oil rings.

Put your Nitto rods in your motor and forget about it mate.

In my experience it is a little more complicated than this. It depends on what the engine is used for.

I'm not an RB expert, but have built many (way to many) Datsun L series performance engines.

The oil squirter on the big end of the the conrod is for oiling the cylinder bores and the piston small end. Thus (at least in Datsun engines) it must be aimed towards the thrust side of the block.

That said, I have run engines with and without them. Here are my thoughts / things to consider:

1.) If you are running too high an oil pressure the amount of oil aimed on the cylinder wall / piston will be too high and lead to smoking / oil consumption. In my experience, up to about 75~80psi in a Datsun engine is ok, 80~100psi = too much oil on the bores. I'm guessing RB's would suffer from this too (although not sure of the pressure at which this would occur)

2.) If the engine is a race engine and the squirters are peened shut (or not existent) the cylinder walls / piston pins rely on the oil thrown off the crankshaft. Peening the oil squirter shut helps with big end oil pressure as none of it is lost in oiling the walls / pistons. In this case I did not run a windage tray, as I wanted that oil to be thrown around.

3.) If the oil squirters are closed or not existent, you are relying on the motion of the crankshaft to throw oil onto the pistons / bores. This works ok in a race engine where the RPM is normally sitting between 5000 and 9000rpm (at least on my Datsun engines) but does not work that great at low RPM (ie a city driven car)

4.) On teardown / inspection of various engines I have found the big end bearings have less ware when the squirters are closed, however there is more bore / piston wear on the thrust side, especially on engines which I have driven on the street.

So, in all the engines I build now, I add two groves (as suggested) to the big ends. Offset slightly so oil is aimed at the piston pin and also the thrust side of the bores.

Attached is a picture of a Datsun conrod for comparison (as well as a custom conrod and custom JE piston I am about to use.)

Just my 2c - think about what the engine is going to be used for. Street - notch the conrods. Race - leave them out.

Edit - and don't forget to re-balance the rods end for end after they are notched (if it's going to see any high rpm)

post-59782-0-11151200-1377032538_thumb.jpg

Edited by datsun_1600
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