I know this has probably been covered a million times but does the RB25ET head bolt straight onto a n/a rb30 block. or does the head need to be n/a as well? cheers Brett

don't you mean RB25DET?

fsck that time for a ... 2jz..no sh|t...

yes it will bolt straight up if it's.... ET.... but if it.s DET it won't....

Skylinesaustralia.com.au i think has a full guide on this conversion. If you get a non vvt version I think its a straight bolt up pretty much. Otherwise the oil galleries need to be modified.

oh k thanks, do you guys think that it is a waste of time putting an rb25 head on a rb30 in a vl would be good considoring it wont be turbo. just rev harder wont it

Quote: Originally Posted by JBA05 yes it will bolt straight up if it's.... ET.... but if it.s DET it won't.... What are you talking about? Theres no such thing as an RB25ET, and the RB25DET head will bolt straight on, but VCT models will need to have the gallery welded up or supplied with an oil line to the front of the head. Regardless of VCT, they all bolt straight on to the block I'm pretty sure.

Quote: Originally Posted by hinto2 oh k thanks, do you guys think that it is a waste of time putting an rb25 head on a rb30 in a vl would be good considoring it wont be turbo. just rev harder wont it Unless you have management, utterly pointless. It wont rev harder without being tuned. An then, spending $$$ on management for a N/A isnt really cost effective for a poofteenth of a kw you'll get from it.

is it worth it? yes.....IF ur prepared to spend lots of money on it ur prob better off going RB26 head or just even easier, buying an RB26DETT and bolting that in I think (and this is just going off the top of my head) that u have to get the bottom end balanced or its no good at higher revs, aftermarket computer is needed, different pistons are better but prob not essential, and yeh oil galleys dont line up on the VCT RB25's (best ones to get are the R32 gts25t or watever they are im pretty sure) have a search around theres plenty on it but if u were after the cheapest option id probably just put an RB25 in it or just do some light mods to a 30ET Some original photos have not been recovered yet.

rb25 for sure--- or just turbo it-- oh nah dont actually

He is talking a RB30DE here... non turbo!

Didn't Zoom mag do a RB30DE (no turbo) and get a 30% increase over the std RB30E...??? Hugely more efficient head than the single cam...

Quote: Originally Posted by TOBES Didn't Zoom mag do a RB30DE (no turbo) and get a 30% increase over the std RB30E...??? Hugely more efficient head than the single cam... Ya but for extra money, like $500 extra you can get a running 25det, break that up, 3ltr it and get atleast another 20% on to of that. Go for the turbo unless your under the new P plate rules ie. no turbo Great conversion either way. standard gear like injectors, computer, manifolds will still have your car goin real well so no need to spend big on aftermarket items

well, vls redline at 5500rpm yea? and r33s redline at 7000rpm. so if u put the rb25 head on, then wont it rev like the r33 only have the torque of the 3litre

Quote: Originally Posted by hinto2 well, vls redline at 5500rpm yea? and r33s redline at 7000rpm. so if u put the rb25 head on, then wont it rev like the r33 only have the torque of the 3litre they are 2 different engines! its not just the head that will make your engine rev harder. the stroke has a lot to do with as do the cams

I would turbo it. Due to the different comp ratio drop. GT30/40 or and 35/40 and you will make some good power.

yea well im only 16 so money is a little problem. i was just gonna slap the head on the rb30 n turbo later, n make sure it has a good gearbox(rb20) n chuck in a minispool hehe.

Quote: Originally Posted by hinto2 yea well im only 16 so money is a little problem. i was just gonna slap the head on the rb30 n turbo later, n make sure it has a good gearbox(rb20) n chuck in a minispool hehe. you will need to save heaps!!! if you want to do it propperly- the poor man pays twice!!! sorry to say it not as easy as "slapping" a twin cam head onto an rb30!!! then turboing it later. if you are going to build one evenually, plan it from the start. A turbo engine has far different requirements then an N.A. rb20 gear boxes aren't good. thay are pretty weak. if you want a good manual box, then look no further then a box from an rb25det.

but the rb20 gear box is a good upgrade, specially for an n/a. i dunno i was just throwing ideas around, maybe ill just keep with the single cam... work the suspension n diff, then a gearbox then bolt in a turbo motor, maybe a rb25, even with a rb30 bottom end already on it or just straight rb25. depends on money i guess. i know this is in the wrong forum but if any1 has a cheap vl they wanna sell me for like a grand from Adelaide ill buy it lol

You realise a RB30DE will never pass emissions ye? Being its a non-factory spec motor you'll have to go through the testing ringer and to my understanding, SA isnt exactly kinda to modified cars in many respects. RB20 gearbox might be an upgrade, but for $800-$1000, you gotta ask yourself is it worthwhile? If you wanna chase power later, the RB20 box simple isnt worth it.