Need Some Help

[Morgz32]

ey fellas

need some advice, i wanna build a hybrid motor with an RB30 bottom end with either a RB25 or RB26 head. the dilema im having is trying to find out which head will bolt straight on with the least amount of modifications? ive read some of the threads on RB30 conversions but still cant find one that will answer my question

cheers

[Nic_A31]

Some info at the bottom of this WikiPedia article:

http://en.wikipedia.org/wiki/Nissan_RB_engine

[R32 Driver]

Theres an rb30 sub-forum in the force induction forum

rb26 is a direct bolt on but the block will need to be tapped out to take the 12mm headstuds

rb25 needs an oilfeed for the vct uses 11mm studs and are a direct fit to the block rb30 is 11mm (head needs a lil modding)

plus side is rb26 has a much better looking plenum however if its going into a gtst it will cost alot for custom piping (easily 2-3k) if u opt for a forward facing plenum

i think cubes has a rb25/30 with a low mount on the stock manifold with 400hp

the rb26 can mount a pair of -10s onto the stock manifolds (see Marko R1s thread)

[GTS-t VSPEC]

In this thread, at the bottom of the first post is a zip file containing a PDF with all the info you need.

http://www.skylinesaustralia.com/forums/R3...ion-t15420.html

[SKYRYAN]

There is an RB25 head from a non-turbo r32. It doesn't have the VCT crap. A lot easier but they're harder to find.

That's the one you want if you can't afford an rb26 head.

[bubba]

The head Ryan is talking about (R32 RB25DE) is the EASIEST head to use if replacing an RB20 as everything plugs back in and will run on the stock ecu (which you can then have remapped).

If you have any specific questions, feel free to shoot me a PM

[Morgz32]

also just wondering what size fuel pump and injectors i may need.. i wanna make between 350-400hp and ws thinking of using a BOSCH 044 fuel pump and 500-550cc injectors??

[N I B]

Missinglink has an RB25 non VVT head, send him a PM.

[Morgz32]

Hey guys

Ive tried surfing the net but i cant find the appropriate information. I'm just wondering if any knows or has a link to a website or a picture that shows the timing belt assembly of an RB25/30DET motor?

Also ive been hearing that i may have to put a new tensioner onto the block for the timing belt to be able to go on?

Whats the best way to get a good compression ratio with good response out of this motor?

Is it better to use a RB25DE or RB25DET head for this kind of conversion for results in compression and response?

thanks

Edited August 26, 2009 by Morgz32

[Morgz32]

hi gtst v-spec i tried opening that file for the build but its a winzip format and i cannot open it or save it and then open it.. any other ideas or does someone have it that and would kindly send it to me??

thanks

[Nak]

whats your email as i may be able to send you the opened copy of zip file pm me it if you still want it

[Topaz]

hi gtst v-spec i tried opening that file for the build but its a winzip format and i cannot open it or save it and then open it..

You can't open a Winzip file?! Opens fine for me. Windows XP has an unzipper installed by default.

[bubba]

Hey guys

Ive tried surfing the net but i cant find the appropriate information. I'm just wondering if any knows or has a link to a website or a picture that shows the timing belt assembly of an RB25/30DET motor?

Also ive been hearing that i may have to put a new tensioner onto the block for the timing belt to be able to go on?

Whats the best way to get a good compression ratio with good response out of this motor?

Is it better to use a RB25DE or RB25DET head for this kind of conversion for results in compression and response?

thanks

Yes you will need to tap a new location for the tensioner, should be in the build pdf I think.

What are you doing with the bottom end? forging it or leaving it standard?

Standard, you're better off with the 25DE head for compression reasons. If you're forging the bottom end then get some twincam 30 specific pistons and use the 25DET head.

[GTS-t VSPEC]

hi gtst v-spec i tried opening that file for the build but its a winzip format and i cannot open it or save it and then open it.. any other ideas or does someone have it that and would kindly send it to me??

thanks

Here is the PDF File

rb30_dohc.pdf

[Morgz32]

yea im leaving the bottom end standard with new piston rings.. thought as much about the head.. that means i would have to change the wiring harness??