Oil Control In Rb's For Circuit Drag Or Drift

[lazyboi444]

Thanks guys for the help.... Can't wait to get this done to mine....Because my motor is out for Top end build and re-assembly and i might as well do that and the restrictor while its out.....This is a good as thread. lol. Thank god for the Aussie's.

[Duncan]

I did the same charlie, and it also fouls on the standard lines that run around the back of the head (boost lines I think), but you can sort it all out

[lovethatboost]

So would there be any issue welding the plug below the oil level for the external oil return?

I bought the rear drain kit from Dane at Densynz and he instructed to weld the plug below oil level because high crankcase pressure would cause the oil to stall inside the line..

There are two takes and i'm confused which one is the more functional route..

[lazyboi444]

BUMP

[Cubes]

So who's blocked off the rear oil feed of their RB20 or R32 RB25DE non-vct head? (i.e only one restrictor feeding the head)

I've tried to see if the two feeds within the head are joined and be buggered if I can feel any vac through the rear feed. :S

Maybe its the way I'm testing it. I've blocked off everything there is to block and there is a good deal of vac on the one oil feed yet the other see's nothing.

[r33_racer]

I believe you can probably run it above the oil level so long as its on the exhaust side i think(could be inlet, have to check with someone who knows exactly) so the crank vacuum helps pull the oil out of the return. I would think exhaust side, as the factory scraper breaks the vacuum from the inlet side so it also being the low point of the sump would be coping all the oil and broken windage. Need gary to cross check my thinkings, he would know for shizzle.

[Cubes]

I've been putting it off for a very long time.

Finally bit the bullet put faith in SK, closed my eyes blocked off the rear, 1.5mm up front and there appears to still be plenty of oil flicking around in the cam covers. I'll put a few hundred kays on it and check it out but I'm certian it will be all good.

R32 RB25DE head.

[Cubes]

I think an Apology is in order for Gary (Sydneykid).

I doubted his suggestion that a 1.5mm restrictor up front and rear blocked off was perfecty fine for the R32 RB25DE head with no VCT.

So I went and did it anyway and it is 100% percent fine.

Plenty of oil up top; top ends nice and quiet; no tapping when it comes off a rev; its all good.

So my apologies Buddy!

-----

I've checked catch cans and there's absolutely no blowby; completely dry.

[Guilt-Toy]

he wasnt the only one who told you..

/me goes through his sent PM's. =)

works good... mine still has lots of oil up there as well.

[Cubes]

Yours doesn't count as you have an additional feed via the VCT to the head.

My problem was I didn't know of any one with an Rb20DET or R32 Rb25DE non vct head that had run with 1 restrictor blocked and a 1.5mm up front. The R32 Rb25DE and Rb20 heads are near identical apart from slightly larger ports and the larger combustion chamber/valves etc. So I wasn't completely comfortable using the R33+ Rb25 VCT head as a comparison that it really did work without problems.

But yes.. Still more than enough oil floating around; I've noticed I can now see the top of the bucket where as prior oil was constantly filled 1/4 up the base of the cam so impossible to see the top of the bucket.

[Guilt-Toy]

wooahhhh.. thats alot of oil up there you had.

[Behind Horizon]

Hello guys, i think it was already mentioned but do you have any sources for the block off and 1.0mm oil restrictor for my RB25DET ? Where can i buy them ? Tomei is only selling the 1.5mm oil restriktor and no block off plug. Thanks in advance.

[r33_racer]

machine one up to about 6.05mm and bash that in...or you can tap it and use a grubscrew instead.

[humz]

can anyone confirm with 100% certainty whether the oil drain from the rear of the head is on the LSH (ex side) or RHS (in side)

seen all the pics and read everypage, and have come across conflicting info.

SET IT STRAIGHT

[Craved]

oil drain is on both sides of the head/block

[T04GTR]

one thing i dont get is.. all the machining etc etc. lining up the gasket etc.. just how much oil do you think will have to "build up" to flow down the standard oil drains. all 18 of them. i rekon mayby 2-300ml at most..

i mean its all a good idea but is it really that efective? has anyone done any tests to back this up? like on a circuit car with the standard sump with and without the drain?

or is blowby the issue here, where it all blows up the oil returns slowing the return of oil back to the sump?

[femno]

OMG where is SK?

He hasnt posted for ages and his inbox has been full for like the last month!!

[humz]

oil drain is on both sides of the head/block

i think i may have worded that question in correctly. when the oil drain is ran from the back of the head do you put it on the left side or right side of the sump???

[GTRgeoff]

Dave, watching the amount of fumes/smoke exiting the catch can vent at high rpm on the dyno I'd suggest there is some resistance to the head return flow but not massive. Still not entirely convinced a return is necessary but if you are considering fitting one then at build is the only time that is sensible.

hans, it doesn't really matter but most go left as that is the natural lean of the engine and run it into the sump.

[Duncan]

we tapped the left of the head and run it aroudn the back to the right of the sump in front of the diff - just enough room to fit it, although the fitting in the head will foul the standard boost lines that run around the bacl