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heya people..

anyone know the diameter of the crank at the main bearings and big ends? just to be able to check the block/crank for wear, only picked it up today .. trying to get a guage on the things needed.

Joel , you mention that the RB25 water pump has a different bolt pattern. this mean its not usable? or just that the one bolt doesn't bolt up and you can leave it?

as anyone played around with the teflon style paints for the interior of the blocks to assist with oil draining back to the sump?

Edited by Craved

I'd like to hear about fatz tight arse also. :)

On the note of block -> head oil restrictors, can't remember if I covered it in here.

RB20/25 - 2 x 2.4mm

RB26 - 1 x 2mm

RB26 N1 - 1 x 1.8mm

RB26 Tomei - 1 x 1.5mm

RB30 - 2 x 1.8mm

Be sure you block one off fatz.

As I'm running the rb25 head I'll soon be running 2 x 1.5mm tomei restrictors. They pin punch down on top of the origional ones.

Running 2 x 2.4mm restrictors my rocker covers are being filled with oil even though the return had been honed to improve oil return. :laugh:

BUT I am running a rb25det pump that sees ~6.5kg/cm2 or what ever it is at high rpm.

I know some one who has a spare.

New from tomei, I believe they are worth ~$30. There is a mob in australia that makes them up also. I forget who they are but they are well known. :

ahh ok, will look around, might also ask my mech if his engine builder can fabricate or locate them for me..

pretty sure he'll want to know about it, think he is building an RB30 for majanal's r33 ..

Joel, your guide says you need to adapt another oil return line from the head when using the R33 RB25 head

is this just a modification of the existing return from near the power steering pump? to return into the turbo return line rather than back into the block direct as standard on the RB25?

will check it all out tomorrow. i have my S2 block at home now finally..

see if there is a related return point on the block like the RB25 ..

http://img68.imageshack.us/img68/8546/untitled1ko.jpg

is a pic of the RB25 return... see if something corresponds on the rb30 block.

i'll have a look tomorrow, im at work at nights so i can check when i get home ..5am :)

but by the look of that pic i posted before.. it looks like it connects to the white rubber hose just below the exhaust runner from Cyl 1..

had a long google search.. found these 2 shots that show the return for the head

eng4.jpg i know its small link http://www.japimports.com.au/products/jap/...images/eng4.jpg cos pic wasn't showing for me

272.jpg

Edited by Craved

i would only suggest running that oil drain on your 30DET if you have re-routed the VCT line so you can use it. the VCT oil feed (via the front cam bearing face trench) is quite a large one, much larger than the other cam bearing oil feed holes.

in addition to this, it does not matter if the VCT is ON or OFF, all that oil still gets dumped back into the head somehow, so you're ALWAYS getting a fair bit more oil in there.

thinking about it logically, any RB25 head that doesn't run VCT from the factory didn't have that extra drain. so if you've disabled your VCT, don't worry too much about the extra drain.

Another concern is the rb25 heads that don't run vct also ran lower pressure oil pumps.

I've seen this already with regards to bl4ck32's motor. Its identical to mine apart from the oil pump (rb20 for him, rb25det for me), literally identical as it was built at the same place at the same time.

Higher oil pressure at high rpm does squirt more oil in to the head, possibly one reason why the N1 motors with their slightly higher pressure oil pump ran a smaller oil restrictor.

I don't think its black and white, there are many variables. :D

double checked on a mates R33 while on lunch, there is a fitting tapped into the block just behind the power steering pump, have to look to see if there is a flat surface on the RB30 block that matches that can be drilled out to supply the drain location..

found a side on pic of the rb30 block on meggala's site

exhman.jpg

doesn't look like there is an available point to tap into for the return line...

perhaps just straight into the sump itself, or into the turbo return.

Edited by Craved

Im also interested in the whereabouts of the restrictors..got a 25det head going on rb30e block.

As for that oil return I would say maybe into the top wing of the sump somewhere. Though the guide says T'ing into turbo oil return, if its not a great thing to do maybe add that to the guide joel and when we come up with a solid 2nd solution it can be added.

Cheers.

I know of a couple people that have T'd in to the turbo oil return, they are having no problems.

I know of one person have problems and they are T'd in to the return. It could very well be something else, they are running the N1 high pressure oil pump without modification of oil restrictors. Possibly the real issue.

just got the g/bos off the rb30, checked it out, there is definately no where to tap into on the rb30 block for the return line on the rb25det head..

also noticed that the heater line connectors (the green agrden hose type fittings) from the rb25 have the screw points but are not open, im guess you have to drill those out to get the water feeds.

anyone be interested in better side shots of the 2 engines next to each other for comparison? can take some once i go get another engine stand.

I know of a couple people that have T'd in to the turbo oil return, they are having no problems.

I know of one person have problems and they are T'd in to the return. It could very well be something else, they are running the N1 high pressure oil pump without modification of oil restrictors. Possibly the real issue.

i'll flip the rb25 block i have over and see where that taped line goes to, if its just into the sump then im guessing it would be fine direct into the sump on the RB30 ..

just thinking about the volumes of these return lines, if the volume gets too high it might cos a block

in the system and not allow the oil to return fast enough.. just a thought.

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