RB30 Which block?

[leeroy_25]

Just a thought on the blocks. I gather the end face needs to be a machined smooth finish to mount the second belt tensioner. do all the series 2 VL blocks have this? And if not is it just something I could do on a mill?

Thank you
Lee

[fletch.rb30]

Originally Posted by leeroy_25

Thanks for the info guy's!

Fletch if you find those CAD drawings let me know as it will save me having to redraw/model them myself! I was intending a DIY job if I go this route! How Did you get the drawings? A bit of trial and error on getting the correct profile? reverse engineer something? What does the 'complete kit consist of? what other bits are needed exactly? crank collar? How is this fitted by the way?

Cheers
Lee

i spent hours with a rb30 block, rb26 block and a 4wd sump, autocad, and a ruler.

The drawings are long gone, i got them laser cut from 8mm plate and the holes cut with the laser also. you need a modified pickupm you can do it without the external pickup. and a bunch of 6mm countersunk and 10mm cap screws of varying lengths.

the crank collar is to make the oil pump drive wider and prevent damage to the oil pump under high loads, look on skylines australia forums, there is a thread with like 300 pages about rb30 conversions, you will find out everything you need to know, also do a google for rb30dohc.pdf. it has a lot of good information in it including drilling for the front tensioner, i have done it with a battery drill, 8.6mm drill bit and a 10mm tap, just make sure its square

[leeroy_25]

I have been told that the non-turbo RB30 bottom end is different in that it has different internals and compression? is that correct? So that would mean the block I require must be a turbo motor if I plan on trying to use the same internals?
Can someone please fill me in.
Thank you
Lee

[fletch.rb30]

they have lower compression pistons only i think.

for example if you ran the 25 head on the 30e bottom you would get around 8.3:1
the 30et bottom end will give you something in the mid 7's

plus the na motor is waaayyy cheaper

[hytech]

Originally Posted by leeroy_25

I have been told that the non-turbo RB30 bottom end is different in that it has different internals and compression? is that correct? So that would mean the block I require must be a turbo motor if I plan on trying to use the same internals?
Can someone please fill me in.
Thank you
Lee

I run the RB30 non turbo block in my GTR, and as fletch said they are a dime a dozen.

[leeroy_25]

okay.. I will be running an Rb26 head. So are you saying I can run the non turbo higher compression bottom end without it going bang?! With the high compression pistons? Surely not? on the other hand if you say I can run the higher compression bottom end then why would anyone bother getting the low compression turbo motor and give away a handful of horses for no good reason?!
Thank you
Lee

[hytech]

Originally Posted by leeroy_25

okay.. I will be running an Rb26 head. So are you saying I can run the non turbo higher compression bottom end without it going bang?! With the high compression pistons? Surely not? on the other hand if you say I can run the higher compression bottom end then why would anyone bother getting the low compression turbo motor and give away a handful of horses for no good reason?!
Thank you
Lee

So you are running the std cast na pistons? Thats fine. We build a lot of drift RB30/26/25 engines with what you have discribed. Just don't put to much boost into it.

Nobody I know of uses the turbo motor.....In fact never seen one.

[leeroy_25]

Thank you for that. Currently I am just exploring my options and doing some research before I dive into it! When you say not too much boost how much can you get away with? My aim at the end of the day was 600bhp. Keeping a stock bottom end and putting suitable cams, single turbo and supporting Mods on my RB26 head. Am I dreaming or being realistic? Last thing I want to end up doing is blowing the bottom end up! I presume you could mahcine the standard pistons a bit to lower the compression if need be> However I always that the turbo pistons are normally a bit more heavy duty to take the boost in the first place?
What compression ratio is a standard RB26 motor?


Thanks again..
Lee

[R.I.P.S NZ]

600hp is no problem for a well tuned stock internal RB30 bottom end.
The stock N/A pstons are just fine with the 26 head, the CR is perfrct for a pump gas, street, 1.5 - 1.7 bar motor.

There's a bit more to it than some will lead you to believe but it is a very common thing you are wanting to do.

Best of luck to you,

Rob

[leeroy_25]

Cheers for that Rob..

Can you elaborate on the complexities of the transplant?! I currently have been informed of the following requirements when going to an RB26 head:

Spacer plate for 4wd sump
Oil pick up pipe mod require
Must have oil feed and return in block
Water feed required
block requires smooth machined finish above water pump to allow for fixing position for additional belt tensioner.
Is a special cam belt required?
Headbolts are a different size. (block needs tapping with bigger threads or sleeve head??)

So far that is all I am aware of.. i haven't finished reading through a couple of build threads yet so I expect there is more.. but as long as it's not too much more involved than any of the above I'm game!!

[gibson]

lee good to see you are still on the trail of info. But just to point out to you all the info you are seeking was on the SAU build sheet that was e-mailed to you. I have done my RB30 and i'm just a tall wavey haired stud ( i wish ) with little knowledge of any thing. Its only an engine there is no voodoo about it. The Rb30 E series 2 ( which had the oil and water out lets that we need ) block will be fine and you can run standard internals replace teh bearings hone new rings and off you go a few holes and moving a few things about easy job done. To my knowledge the RB30et was no different the Rb30E engine was just treated with more respect (not had the ass scr**ed out of it)
Just My 2P

A famous singer once said " don't believe the hipe" well its true

[fletch.rb30]

RB30 DOHC Guide

there is most of the info here, basically its an normal engine rebuild, eg, rb20/25/26 hone out, new rings and bearings etc, but with rb30 block. you have to drill and tap the front of the block for the tensioner, its already flat, just need a ruler and a dot punch.
For a few dozen beers i could be convinced to draw a new adapter plate and with the use of a tig or oxy set, mod your stock pickup.

I have fitted a rb25/30 to a r32 gts4. it was pretty easy, i did it all myself to keep costs down, only engine work was the usual hone/acid bath/frost plugs/head and block surface/valve grind and stem seals(thanks hytech ). Its making 300kw at the wheels on 18-20psi and hasnt missed a beat.

I have a few mates running rwd rb25/30's all with stock internals,new rings and bearings, none have failed yet... and they all get a hard time. I will try and find some pics

[fletch.rb30]

gts4




Its pretty hairy under the hood, but it has been tidied up since these pics were taken. greddy copy inlet manifold, stock 20/25det exh manifold, turbo spacer with 46mm gate, gt35/40 1.06 turbo


Clint's 318 bmw e30.


its a tight fit but its in, runs a manualised auto, xr6 falcon irs rear end, and some really big feet
stock rb30 internals, honed and acid bath, new frost plugs etc, stock 25 vvt head, greddy copy inlet manifold, t3/t4 turbo


Ray's 69 datsun 2400, factory h190 diff shortened a few mm each side, r32 rear brakes, 600sel merc discs up front with r32 front calipers.


Its on its second motor, the first is still running, but was thought to be sold so removed and another built with knife edged crank and otherwise stock internals. Rays a machinist and saw a friend knife edging a crank so he gave it a go and turned off the counterweights. This motor was literally assembled with a rattle gun and a hammer and its pretty mental.
Fancy steampipe manifold, twin 38mm gates, gt42 sized turbo, modified rb25 inlet manifold, straight thru 4 inch exh



Apart from rays crank, all the engines are stock rb30 with new rings and bearings and are driven pretty hard and are all still running mint. Must be due to hytech's top quality machining

[gibson]

Really nice.. fletchRB30 .. The rattle gun and hammer approach i'm not sure on, but get the idea.
The RB30 Is the way forward
What oiling additions where done on these RB30 builds.??

[fletch.rb30]

the first motor in rays car i brazed some steel onto the block at the front water gallery to make it accept the vvt head gasket. i think it ran a stock rb25det gasket. after it was welded we got it skimmed and im pretty sure we didnt block off the oil gallery in the head face as it was blanked off by the extra metal in the block.
After that we got the engine builder to give the heads a shot with the welder (then skim the head) to block off the vvt oil feed and also make the water gallery slightly smaller to mate better with the rb30 block, im running stock 33gtr gasket and the others are running stock rb30e gaskets.

External feeds made out of 1/4 stainless tube were made up for my engine and both of rays, drilled into the oil gallery behind the cam pulley and fed from a tee in the oil pressure sender.

i blocked the front oil feed and restricted the rear feed down to 1.5mm, and also welded the fitting up for the vvt feed and drilled it out to the factory 1.5mm to restrict the flow there too, otherwise when the vvt is off, there is an open 2mm drain from the vvt solenoid directly into the head and oil pours in.

On clints motor, there is no vvt feed. There is a brass plug blocking the inlet side lifter gallery. we removed that and put a shorter one in with a 1.5mm hole drilled into it so the vvt is fed from the main lifter feed.

oil pumps are either stock used gtr or n1. whatever was cheap all have crank collars