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Over the years a few guys have asked me to post up some pictures showing the engine mount redrilling required to fit the RB31DET under the R32GTR bonnet in the R32GTST. So here we go;

Driver's Side

gallery_1903_3306_631598.jpg

Passenger's Side

gallery_1903_3306_394066.jpg

Any chance at all some one can point me in the direction of info solely regarding using a rb25de head off a r32 on the rb30 bottom end? it would be greatly appreciated.

thanks

Should be in this thread somewhere. If you want to know anything specific then PM me or post up here. I used an R32 RB25DE head and it was pretty much straight bolt on and plug and play with my 32GTSt ECU.

Should be in this thread somewhere. If you want to know anything specific then PM me or post up here. I used an R32 RB25DE head and it was pretty much straight bolt on and plug and play with my 32GTSt ECU.

hi mate.

thanks for the reply. i thought there may be a separate thread for the r32 rb25de heads seeing as there is nearly 350 pages in this thread but ill have a skim through untill i find it.

thanks.

Any chance at all some one can point me in the direction of info solely regarding using a rb25de head off a r32 on the rb30 bottom end? it would be greatly appreciated.

thanks

The first RB30DET I ever built used an R32 RB25DE cylinder head, shoot that was over 10 years ago, I feel old. It is the best low cost head you can use on the RB30, with no VVT to confuse the issue, it's a straight bolt on. The reality is there is no need for a separate thread, it's so simple. You can use the RB30 guide, just ignore the bits about modifying for the VVT, you don't have to worry about that. So you can use an RB30 or RB26 head gasket. Everything else, pulley positioning, head bolts etc is the same.

Cheers

Gary

  • 2 weeks later...

what headgasket do i use to put a rb25det head on a rb30 block? i bought a rb30 one so i hope its right. some of the holes are different so i dunno.

and with the right gasket once i confirm which one and with the hole on the head welded up its a straight bolt on isnt it? like where the oil gallery i think it is at the front is a different shape near where the hole is welded up is it ok to just bolt it together with the different shaped holes together?

The first RB30DET I ever built used an R32 RB25DE cylinder head, shoot that was over 10 years ago, I feel old. It is the best low cost head you can use on the RB30, with no VVT to confuse the issue, it's a straight bolt on. The reality is there is no need for a separate thread, it's so simple. You can use the RB30 guide, just ignore the bits about modifying for the VVT, you don't have to worry about that. So you can use an RB30 or RB26 head gasket. Everything else, pulley positioning, head bolts etc is the same.

Cheers

Gary

thanks heaps for that Gary

did you ever play with cams ect on the R32 rb25de head? what can you use? rb20 or rb26 cams?

thanks damo

thanks heaps for that Gary

did you ever play with cams ect on the R32 rb25de head? what can you use? rb20 or rb26 cams?

thanks damo

Hi Damo, I just used the RB25DE standard cams with adj pulleys. It had plenty of power in 1999, ~400 rwhp, from daggy a T04E that we had lying around. Had to keep the cost down, the whole RB30/25DE cost less than $1200.

Cheers

Gary

  • 2 weeks later...

Hi all!

Im planning of using the series 2 RB30e block, stock for now, with stock RB25DET head (new turbo inj. etc).

What do you reckon the compression will be?

Also will the spring valves be in the risk of floating if i keep the revs >6500 rpms?

Cheers!

Dave

  • 1 month later...
  • 4 weeks later...

ive got a r33 rb25det head that i got modded with the vct hole welded up and the new fitting put in at the front. i didnt get any extra welded on where the gasket seals. do most people get that done or leave it as is? i didnt know about iuntill after i had it done.

if i take it back to the shop and get more welded to the area and then resurfaced will it effect the compression or make the valves hit the pistons or anything from being resurfaced too many times or anything?

would it be fine how it is? ive got a rb30 gasket. is that the right one to use?

i had read the guide and printed it out and dropped it off at the machine shop when i got everything recondiotioned but didnt realise about adding extra to where the gasket seals

  • 2 weeks later...

I must be a retard because I cant find what I am looking for even though I am sure its somwhere...

If I am going to put forged RB25 pistons (20 thou oversize) and eagle rods out of the same motor into an RB30 block, will comp ratio still be reasonable (8:1 or 8.5:1)? This combination will be fine I assume as in the .pdf its stated that bore is the same between 25/26/30. The rods are my concern but I am pretty sure they are interchangeable.

Sorry guys :banana:

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