R33 Rb30 Conversion

[satanic]

NRGR34 - good luck to you then I for one would be doing a lot more research before just saying "3.0L my car"

[R34NRG]

  Cubes said:

Its difficult to find a decent 26head for a 'reasonable' price.

Stick with the R34 head, nothing wrong with it. It runs solid followers and you have the plenum which is a big bonus.

No problems. Its an easy conversion in the RWD.

Technically you shouldn't be charged a great deal more compared if you were going to swap another rb25 bottom end under it.

The only real mods off the top of my head for yourself will be the powersteer bracket, dump pipe, drill/tap of the upper tensioner, run the VCT oil supply, block off the block to head vct oil supply, run a front oil drain.

So not a great deal.

yeh ur right its not that expensive its about 1.5k more id say, and the bonuses are 10x more. how much would a 26head go for? i was told aaround 2k maybe? selling the full motor and stuff for around 5 would see me with 2-3k in my pocket. maybe a that flame thrower kit for christmas i always wanted

  satanic said:

NRGR34 - good luck to you then I for one would be doing a lot more research before just saying "3.0L my car"

thats why im here man lol, the car isnt gonna start work for a while, so i got about a couple of weeks before parts are slapped on. basicly they just ordering parts mandatory for a 2.5setup anyway, and lookn into the 3.0 if all goes well, great. if not, ill go the 25 with a smaller turbo

Edited December 13, 2007 by R34NRG

[VB-]

ok so it is me thats advising him to go for the RB26 head. reasons being, he can use the standard GTR plenum and throttle bodies, the motor hes gonna get built will be using an aftermarket plenum, so he has to buy the plenum, then use his head, leacing him with a spare inlet and bottom end worth 3/5ths of f*ck all

my theory is to buy the 26 top end, use that, so he'll save 1k on buying aftermarket plenum, then he can sell a complete RB25 motor, easier to get rid of than the parts he would otherwise have. drawbacks would be that he has to buy another ECU/loom (hopeuflly get loom with head) and may have a few ancillaries missing off the bottom end. what ancilaries will need to come off the 25 to build this new motor anyway? alternator, a/c, p/s?

overall i think it would be worth it but i havent built one of these motors before opinions?

[satanic]

Wrong... if he was to go down that path; the RB25 would be missing a LOT of stuff at the end.

You "could" get away with keeping the RB25 loom to run the RB26 provided you have aftermarket management of some sort (high end; fully programmable)

At the top end; heaps of it is transferable from the RB25 (assuming you want to keep the 25 loom) - there are heaps of things that you'll have to do to make it all work though (can see many dollars being wasted here)

The cheap way to do it would be to get a complete RB26 top end; loom and ecu... as VB- has said; but i can assure you the RB25 won't be anywhere near "complete"

[shanef]

for 650hp ecu choice is a no brainer imo - autronic or motec wire in

[Spoolup]

The easiest way - not nessassarily the cheapest - is to put the NEO head on the RB30 bottom end and use the STD loom with a Power FC.

[VB-]

  satanic said:

The cheap way to do it would be to get a complete RB26 top end; loom and ecu... as VB- has said; but i can assure you the RB25 won't be anywhere near "complete"

so what else is needed from the RB25 if he sourced a 26 top end?

[satanic]

Depends whether he chooses to keep the 25 loom... if he does then he'll need to keep all the sensors; wiring plugs from the RB25DET NEO top end won't he? I won't go into detail - I'm sure he'll (or whoever is doing it) will find out soon enough.

[R34NRG]

hows it going guys, more questions from me

was thinkin the other day since im gonna be runnin 3.0L would exhaust housing size would be efficient with a gt35?

obviously a .65 is out the window but would a 1.06 be to large and laggy? im leaning towards a .86 but wanted ur opinions on the larger one.

[SirRacer]

its in all of the previous pages dude, you just need to do a search.

ive gone .82 which seems to be a good mix, however ill be upgrading soon as im going to go for maximum power so ill post up some before and after dyno results

[R34NRG]

  SirRacer said:

its in all of the previous pages dude, you just need to do a search.

ive gone .82 which seems to be a good mix, however ill be upgrading soon as im going to go for maximum power so ill post up some before and after dyno results

yeh im actually after the exact opposite, i dont care alot about top end hp im after street ability. dyno sheets would be great buddy. wat turbo u runnin?

[Cubes]

I probably wouldn't bother with the 1.06 on the RB30.

Sky30's pulled only 'just' under 400rwkw out of his GT35r .82 on his RB26/30.

Step up the turbo size.. Unsure as I've never really looked in to it but possibly a GT40/42 or T04z? sort of thing if you want more?

[R34NRG]

  Cubes said:

I probably wouldn't bother with the 1.06 on the RB30.

Sky30's pulled only 'just' under 400rwkw out of his GT35r .82 on his RB26/30.

Step up the turbo size.. Unsure as I've never really looked in to it but possibly a GT40/42 or T04z? sort of thing if you want more?

like i said before im not realli about big numbers unless i can plant that shit. no point gettn 400rwkw if i can only use 30% of it.

how much pound was Sky30 using?

[rockabilly]

Sky30's pulled only 'just' under 400rwkw out of his GT35r .82 on his RB26/30.

nice . i wonder what my 1.06 rear will do then. was hoping for 400rwkws,,,cheers cubes

[Adriano]

Hi, im building a rb25/30 for a friends car, and have two options for the camshafts, either retain the NEO cams, VCT and fit an exhaust wheel(which i already have), or fit a pair of rb26 cams with adjustable camwheels. Car will probably be running a .86 GT35r, and hopefully making about 330rwkw with 18psi. Comp will be 8.8-9:1. Does anyone have any solid advice?

[Cubes]

  R34NRG said:

like i said before im not realli about big numbers unless i can plant that shit. no point gettn 400rwkw if i can only use 30% of it.

how much pound was Sky30 using?

My reply was for SirRacer but yeah.. Its in his sig. From memory around 19-20psi or something. Not all that much boost but I believe he is running some reasonable cams.

[[200]]

I am about to buy some injectors.

I was looking at the bosch 'indy blue' 1600cc ones. I don't think these would be a straight 'bolt in' ... or am I wrong? What mods are needed to fit them?

Edited December 17, 2007 by [200]

[Dahtone Racing]

wat kind of compression test results have people got with RB25/30s????

[Spoolup]

If the GTR cams are better ( bigger lift and duration ) then the R34 GTT cams, prob best to go with the GTR cams. As in there std from they are still very streetable. You will easily be able to make the power you want with them.

Std cams are a pleasure to drive around with compared to say the 272's I have. You get the streetability with the std cams and also the great fuel economy.

My car has the fuel economy of a 6.0 litre holden around town and then it gets much worse when boosting :-). It is also a dog to drive under 2000 rp.

Big cams will make more power but you definitely lose down low drivability and off boost fuel economy.

  Adriano said:

Hi, im building a rb25/30 for a friends car, and have two options for the camshafts, either retain the NEO cams, VCT and fit an exhaust wheel(which i already have), or fit a pair of rb26 cams with adjustable camwheels. Car will probably be running a .86 GT35r, and hopefully making about 330rwkw with 18psi. Comp will be 8.8-9:1. Does anyone have any solid advice?

[R34NRG]

dropped into racepace today to talk to ben and his opinions on a rb30/25 conversion. his not very fond of the things to my surprise. he wouldnt even take on any rb30/25 jobs. he suggested that i got get some sort of 2.8 HKS stroker kit for 9k.

his main concern is that the 30 block wont fit into the engine bay with all the other crap in there.

wats ur input guys? im kinda put off about the rb30 now. i thought it was a perfect solution for my torque demands.