Oil Control In Rb's For Circuit Drag Or Drift

[fast_cav]

How far do you actually have to drill them??? Drill bit went down a few mm easily then seemed to stop ...Would not go any further???

[Duncan]

The restrictor from factory (and aftermarket ones) is about 3mm deep. Generally people just push any new restrictor on top of an old one, so you need to drill 3 to 6mm. But you should drill it out of the block and then push it in later, you don't need crap in the oil galleries.

[JonnoHR31]

only problem with that is some restrictors get a bit smaller when you put them in. myne went from a ~1.5mm hole down to almost nothing just from tapping them into the block, then had to drill them out again once they were in

[pie21]

The guys at duncan foster in south sydney fit all those drain back fittings to the end of the head for external oil drain back.

They also fitted to mine a fitting to the exhaust side next to the standard drain ,an external fitting there as the engine leans that way so the oil does not pool up

Makes sense i guess???

[pie21]

Not talking about oil restrictors that are fitted to block ,but oil drain back fittings fitted EXTERNALLY as well

only problem with that is some restrictors get a bit smaller when you put them in. myne went from a ~1.5mm hole down to almost nothing just from tapping them into the block, then had to drill them out again once they were in

[TiTAN]

we checked my oil restrictors just recently they were 1.5mm before being installed after pulling the head off and checking them out a 1.3mm drill bit wont fit into the openings

[r33_racer]

A grubscrew restrictor wont have that issue.

Who ever made those ones that are closing up most likely made them too big in the OD. Too much crush!

[TiTAN]

A grubscrew restrictor wont have that issue.

Who ever made those ones that are closing up most likely made them too big in the OD. Too much crush!

they were the tomei ones, but i sent you a long email with far more detail.

[r33_racer]

Farkin Tomei!!!!!!!! lol

Sweet! Replied mate!

[JonnoHR31]

pretty sure myne were the tomei ones too and closed up a fair bit

[Simon-S14]

Quick question. I have a neo rb25 which pushes 350 rwkw and sees a lot of track thrashing and limiter action. Never once has catch can seen oil so oil control is pretty decent. Anyway it's all apart now and I'm getting a crank collar fitted and was going to go n1 oil pump. Will I need restrictors in the block? If so what size do ppl suggest. Cheers

[FineLine]

The best advice anyone here could give you would be to avoid the n1 oil pump like aids.

[Simon-S14]

Are they still no good even with crank collar? From the reading I did the broken ones were used in stock cranks

[FineLine]

They are no good period Simon. Particularly if you are a slider.The constant banging on the limiter will crack the gear as sure as theres shit in a cat.

The last few i saw fail all had the snout extension in place.

[TiTAN]

for someone like you that sees a lot of limiter action stick to the stronger pumps, tomei, jun and nitto or invest in changing the oil pump gears in the N1 to something stronger.

[Simon-S14]

So billet gears in oem housing could be a go then?

What about the restrictors? To be honest the thought of running the oem pump is sounding more appealing with all the research I've done

[Dale FZ1]

A season or two of competition would surely have identified setup weaknesses for the engine.

If you've got no evidence of oil supply/delivery problems, then it sounds like the OEM pump design is ok for the application. Whether that particular pump should be replaced might be an issue to resolve after good inspection.

Are you freshening the engine, or planning on development work and spinning it faster?

[FineLine]

A set of billet gears is a worthy investment. I've seen good results from them.

I cant advise you what oil restriction setup works for the neo as I've had no experience with it.

You still need an oil supply to drive the vct but unlike the 33 head you dont have to feed hydraulic lifters. Surely someone on here has had experience with this setup.

[R31Nismoid]

I've lost count the amount of times I've hit my limiter with my N1 pump. Hell @ the drags i even flat change just for a laugh.

Virtually 12 months on, no issue at all.

Guess you northern people get different N1 pumps to us down here.

[Simon-S14]

Dale. I spun bearings as a result of an oil cooler connection failure. So replacing crank. Bearings and getting crank collar done also. Haven't pulled my pump apart yet but there was very little in the way of bearing material so I may be lucky. However I kinda doubt re-using it is a smart move. Was leaning toasted cleaning and inspecting housing and fitting billet gears. I don't think I'll run restrictors if I go down this path as pressure and flow should remain the same