Rb30 Block

[The Dan]

Not confused...that is the line I am referring to.

I think in his original question he may have been referring to the oil return gallery on the drivers side front of the head where the NVCS oil feed is usually situated.

The oil return on the passenger side can be run back to the turbo return...yes, but not necessary if you have extra oil returns on the back and restrictors in the feed galleries.

[r33_racer]

for a road car that is probably correct, for anything track related you need em all, even with back return and restrictors.

Either way an extra oil return required or not can only be beneficial. But obviously as always these things depend on application and setup.

[r_speedfreak_r]

i will have oil feed restrictors. I heard they are essential to stop all the oil running to the head and leaving the sump dry. Thanks for your help guys. its still all a little blurry to me atm but my engine isnt yet ready to go back together im simply asking due to comments ive heard from others. I'm sure once im putting the two engines together i'll be able to relate what your saying to whats infront of me.

[The Dan]

i will have oil feed restrictors. I heard they are essential to stop all the oil running to the head and leaving the sump dry.

Yes, well there are a couple of theories regarding that little nugget.

[r33_racer]

application will determine everything you do with your build up.

[R33S2]

So let me get this straight,

1. there is no oil supply for the 25 head VVT on the 30 block but you can supply it externally by drilling and tapping a fitting into the oil gallery for the VVT on the head?

2. There is a water jacket that needs sealing on the 25 head?

[r33_racer]

1. correct.

2. no water jacket that needs sealing up completely, if thats what is meant. If there is, we havent done it on either of the two 25/30 weve built for our race car. There is the waterjacket which doesnt have much sealing area for the headgasket, so we built that up with weld to match the headgasket. However alot of people get away with doing nothing for that one.

3. there is no front head oil return fitting in the rb30 block, just the turbo oil return. You can either block that off like Dan suggests, 'T' it into the turbos oil return, not the greatest way or weld a fitting to the sump somewhere for it.

[R33S2]

1. Allright!

2. "There is the waterjacket which doesnt have much sealing area for the headgasket"

So this is an area of concern that requires attention, as I would want a good sealing surface on the head gasket esp. I take it the edge doesnt match the edge of the gasket? ie is behind that line with extra gasket.

3."there is no front head oil return fitting in the rb30 block'

Is it possible to drill and tap in the same place as the 25 block?

[r33_racer]

2. from memory the gasket protrudes into the water jacket so you build up that section of the jacket so it seals on it better.

3. it could be, but the webbing and block design is different to that of the rb25, we looked at doing that but it was going to be going straight through a web i think. From what dan is saying if your running the correct restrictors and rear head return, that you can block off that front one and not worry about it.

Edited February 17, 2007 by r33_racer

[R33S2]

Thanks Michael just one more question.

Where is the best place to use for the VVT oil supply?

[r33_racer]

Oil pressure sender feed. 'T' piece into that feed and run your line upto the fitting welded off the gallery, or if your running the std rb25 heat exchanger then you can run ops off that and your vct feed off the block.

These should help. In the first motor we used the heat exchanger and ran std ops, mech gauge off that and vct off the block. New motor has std ops, vct and mech gauge all off a 'T' piece off block.

[r_speedfreak_r]

hey i just had a thought. If i'm building an engine from scratch would it be worth buying an rb26 head and bolting that on instead of the rb25 head? That way i would have as good of an engine as any gtr just rwd. Is it worth the money and does anyone what you need and how much it costs to make it fit?

[R33S2]

Just so happens some one was asking this in the RB30 thread. http://www.skylinesaustralia.com/forums/in...p;st=4880

[r_speedfreak_r]

going off that thread it sound like the rb26 stock head is better because you dont have to do anything to it. but what do you need to make it fit on the rb30 block and where can u buy everything you need

[shanef]

going off that thread it sound like the rb26 stock head is better because you dont have to do anything to it. but what do you need to make it fit on the rb30 block and where can u buy everything you need

theres a fair few bits of fiddley sh!t that needs doing. everythings posted in the R33 RB30 thread in the forced induction area, so instead of posting repetative questions in here, maybe go have a squizz in the other thread.

[R33S2]

Outa the 123 pages which do you recomend for said research?

[shanef]

prolly the later ~20 pages, basically when i started posting in there (for info on the 26/30)

[r33_racer]

or have this thread with concise and accurate information which answers all the important questions without all the crap.

[shanef]

yeah a fair bit of the posts in there are fairly useless...maybe we should try and get cubes to update his document he has. maybe even offer him a hand in sorting trhough all the posts