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Starting the build of the Rb30, just picked up the RB25 det head (already modified for larger lift cams)

just looking at camshaft options atm..

currently have tomei poncams in my std RB25, but was looking to upgrade to other cams in the rb30/25.

was looking at cams around the 270 to 272 degree mark, but can only find the tomei procams of 270 degree for the S1 RB25.. hks dont seem to have a listing for the pre '97 head .

also need some confirmation of what types of solid lifters and valve springs are required with cams of this size, with revs limited to about 7500-8000 rpm

been reading through a lot of threads and seem to have figures on people use of them but not much detail .. any and all info would be great.

cheers

Chris

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Poncams work well with a 3540 on a Rb30/25 motor.

Tomei sell a solid lifter conversion and type B valve spring kit to go

with there 270 procams.

I am guessing but would like to know aswell, if you buy Tomei solid conversion

it should open the Rb25 head up to use all aftermarket Rb26 cams in theory.

cheers

darren

Edit:don't Tomei sell there solid lifter conversion anymore,,,aaarrgghh, who

else does it??, makes it cheaper to buy a RB26 head then

Edited by S3_Girl

http://hioctaneracing.com.au/eshop/product...&products_id=67

http://hioctaneracing.com.au/eshop/product...&products_id=39

these are still being advertised by hi-octane.. but thats alot of cash ontop of the cam purchase ...

are these the kits mentioned earlier?

http://hioctaneracing.com.au/eshop/product...&products_id=67

http://hioctaneracing.com.au/eshop/product...&products_id=39

these are still being advertised by hi-octane..  but thats alot of cash ontop of the cam purchase ...

are these the kits mentioned earlier?

Yep , they are the ones, that's why i thought you could still get them,

give them a call maybe???

If you are going to be reving it to 7500-8000rpm and want it to be reliable seriously consider having Proengines slap one of this oil pump drive snouts on the crank.

Also consider an ATI balancer, prevention is much much better than a very expensive cure. :S

If you are going to be reving it to 7500-8000rpm and want it to be reliable seriously consider having Proengines slap one of this oil pump drive snouts on the crank.

Also consider an ATI balancer, prevention is much much better than a very expensive cure. :S

yeah i chatted to BU5TER about his when i picked up the head .. just seeing rev limits etc..

might not need to rev that high, but thats the aim.

alot of pages in that rb30 thread .. will search it for the pump snouts, remember reading about them.

aim is as close to 400rwkw as i can get .. due to the 1.12 rear housing im looking for as much flow as i can get it to widen the power curve .

well the bonus i guess is that i can use the poncams that i have already and see what results i get, then decide later if an upgrade is required.

the head has been modified already (bretts old RB25) so it should have the clearance for the larger cams already so the head wont need to come back off ..

The crank collar is only $150 or $300 fitted.. Something along those lines, drop Proengines a PM directly, much quicker and accurate. :P

this collar is to run the N1 oil pump? are they in SA ?

The collar is to distrubute the weight over the whole of the oil pumps internal gear.

The R32 RB26/rb20, R33 S1 and RB30's all run a small crank oil pump drive gear. Basically a missed gear or a little bit of harmonics it causes the internal gear of the oil pump to crack, loosing all oil pressure instantly destroying your motor. :O

All the oil pumps are able to be used with the larger oil pump drive gear.

Also DO fit up a tomei oil restrictor kit other wise you will have the head flooding with oil soon filling your catch can with oil, especially if you run the N1 pump.

Another option is blocking off one of the oil feeds to the head BUT this is a little bit of an unknown.

I consider it safer to simply grab a rb26 tomei stopper headgasket and restrictor kit from nengun. For the price you really can't go wrong.

Proengines are interstate.. not SA. I would post the crank, well worth it compared to the $600 JUN collars + fitting. :S

If its done by some joe blow there's the worry due to lack of experience it hasn't been fitted correctly.

Proengines appear to love the RB's. Can't get better than that. :P

The collar is to distrubute the weight over the whole of the oil pumps internal gear.

The R32 RB26/rb20, R33 S1 and RB30's all run a small crank oil pump drive gear. Basically a missed gear or a little bit of harmonics it causes the internal gear of the oil pump to crack, loosing all oil pressure instantly destroying your motor. :O

All the oil pumps are able to be used with the larger oil pump drive gear.

Also DO fit up a tomei oil restrictor kit other wise you will have the head flooding with oil soon filling your catch can with oil, especially if you run the N1 pump.

Another option is blocking off one of the oil feeds to the head BUT this is a little bit of an unknown.

I consider it safer to simply grab a rb26 tomei stopper headgasket and restrictor kit from nengun. For the price you really can't go wrong.

Proengines are interstate.. not SA. I would post the crank, well worth it compared to the $600 JUN collars + fitting. :S

If its done by some joe blow there's the worry due to lack of experience it hasn't been fitted correctly.

Proengines appear to love the RB's. Can't get better than that. :P

have already spoken to my mechanic about the oil issues within the head . basically honing out the return lines for the oil has the same effect .. he has doen this with a mates CA18DET after it blew the bottom end with that issue.. might also try blocking one of the feed lines. also a process like port matching used on the oil galleries/feeds to assist in the oils movement through the block and head.

probably would keep the RB25 oil pump though, still street driven and might still have the lower revs.. but 7500rpm would be nice due to the size of the housing.

have read a bit on those harmonic issues cracking the pumps in the rb30 thread ..

got some details from another thread with the picture of the crank collar ... good news and would be worth it!

Craved,

When building mine up I questioned the engine builder regarding flooding the head with oil and using oil restrictors.

He said he would prefer to clean up the oil return, basically as you said hone and improve oil return back to the sump.

I checked the amount of oil sitting around in the head last dyno run, unfortunately simply improving oil return back to the sump was not good enough as I could see quite a bit of oil pooling well above what it should be.

God help me if I ran the N1 pump, I am considering pulling the head off and dropping a tomei restrictor kit. :S

I could block one feed off BUT I don't feel comfortable with knowing if there will be enough oil or not.

Do remember the RB30's oil feed restrictors are 1.8mm vs 2.3 or something mm of the rb20/25's.

So blocking off a 1.8mm oil restrictor may indeed starve the head. In the rb20/25 motors you may get away with it due to the larger factory oil restrictors.

Quiz Bu5ter... He's been through it more so than I. :)

The collar is to distrubute the weight over the whole of the oil pumps internal gear.

The R32 RB26/rb20, R33 S1 and RB30's all run a small crank oil pump drive gear. Basically a missed gear or a little bit of harmonics it causes the internal gear of the oil pump to crack, loosing all oil pressure instantly destroying your motor. :cheers:

Cubes, can you elborate on this a bit. When you say missed gear, you dont mean missed gear change do you? Is it worth having this colar fitted for a rb25/30 that will be limited to 475hp and 7000rpm? What about this oil restrictor kit form tomei?

Or is this stuff only neccisary for the more hardcore motors using more rpm and making over 300rwkw?

Cheers

Obviously I can't quote exactly when a oil pump gear will crack as I don't know..

I would have the collar fitted to any 'rebuilt' rb25/30 that I build in the future, the small outlay now (it really is small) will save you $$ in the future should you miss a gear flick it over 7000rpm occasionally.

As a note the vlt/r31 boys do tend to have issues when running the det oil pumps @ ~6600rpm. What is interesting is I haven't seen a stock rb30 or rb30t oil pump fail on the rb25/30 when flicked over this rpm. Possibly due to the design of the pump.

If I were to simply drop in a s/h rb30 I would worry about it.

If I were to spend $$ on forged pistons and the likes I would most definitely spend another couple to few hundred $$ on the crank collar.

Mine doesn't run the crank collar and I have accidently missed third gear once, peak rpm stated 7600rpm. Makes me nervous. :S

The tomei restrictor defeats the rb26's issue of dumping all the oil in the head at constant high rpm. RB26's have the issue so will the rb30/25/26.

I'm far from an expert.. Proengines is definitely better qualified to answer the questions in detail as to why the pump fails.

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