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is that maxing the turbo out? anyone on here selling 25det gearbox by any chance? and another question? are the 26dett gearboxes able t be modified to run on a rwd car?

Edited by Redliner007
is that maxing the turbo out? anyone on here selling 25det gearbox by any chance? and another question? are the 26dett gearboxes able t be modified to run on a rwd car?

There's a search button for a reason, all of these questions have been answered before.

There's a search button for a reason, all of these questions have been answered before.

well i cant seem to find anything about 26 gearbox being used on rwd cars? sorry if im being a neusence, just want to do things right with out sitting in front of the comp all night thats all

well i cant seem to find anything about 26 gearbox being used on rwd cars?

Im doing one myself

http://www.skylinesaustralia.com/forums/R3...-A-t213779.html

http://www.skylinesaustralia.com/forums/Rb...amp;hl=transfer

Every Rb30 question has been answered more than twice in this thread, take the time to read every page and digest the info.

When your done reading this thread theres 44 topics to read in the Rb30 conversions sub forum. http://www.skylinesaustralia.com/forums/RB...sions-f184.html

Edited by Alf

The R32 head is fine for 300rwkw. R33 if your going to push 400rwkw.

The GT3076 .8 rear .6 port shroud comp can be squeezed to 320rwkw with pair of cams. Mine has made 268rwkw on 15psi and 285rwkw on 17psi. Didn't appear to make a great deal after that as we suspect one of the following resulting in a tooth up/down see saw top end:

* The 232 duration exhaust cam was causing a little problem letting the exh gas out

* Some funky ignition break down began setting in (as there was a fair bit of unburnt fuel around when there shouldn't have been)

* Onset of valve float

Waiting for a set of 264 advertised 221degree @ 0.050" 9mm lift cams should be here in a week or so.

Interestingly the exact same thing occurred in a mates rb30det but using the GT35r .82; on the same dyno his made 270rwkw at 17psi much more and it began see sawing. Only real difference between the motors is mine runs a slightly higher comp and my head has had a bit of work (port polish valve deshroud).

The R33 head has slightly larger inlet ports and are more square open looking compared to the R32's twin round tube looking ports. Exhaust the same, valve size the same.

Redliner007 sorry to say mate; reliable, power and cheap do not get used in the same sentence. My build has thus far cost me about $12,000; this was with the rb25 head already ported, cam'ed upgraded and reco'ed (ie: Head not touched during this build). My target was 300rwkw, which is plenty for a rwd car. So if you want to make a reliable 350rwkw, make sure you have deep pockets, as you'll wont get much change from $20,000, to go from what you have now to what you want. This is provided that someone else is doing the work for you, if dong yourself you will save maybe a quarter of that.

PS: I would personally use a GT35R (0.86a/r), if i was aiming for over 320rwkw.

The R32 head is fine for 300rwkw. R33 if your going to push 400rwkw.

The GT3076 .8 rear .6 port shroud comp can be squeezed to 320rwkw with pair of cams. Mine has made 268rwkw on 15psi and 285rwkw on 17psi. Didn't appear to make a great deal after that as we suspect one of the following resulting in a tooth up/down see saw top end:

* The 232 duration exhaust cam was causing a little problem letting the exh gas out

* Some funky ignition break down began setting in (as there was a fair bit of unburnt fuel around when there shouldn't have been)

* Onset of valve float

Waiting for a set of 264 advertised 221degree @ 0.050" 9mm lift cams should be here in a week or so.

Interestingly the exact same thing occurred in a mates rb30det but using the GT35r .82; on the same dyno his made 270rwkw at 17psi much more and it began see sawing. Only real difference between the motors is mine runs a slightly higher comp and my head has had a bit of work (port polish valve deshroud).

The R33 head has slightly larger inlet ports and are more square open looking compared to the R32's twin round tube looking ports. Exhaust the same, valve size the same.

R32 RB25DE is capable of more than 300rwkw, my motor in it's previous car was making 365rwkw through standard 25DE head/manifold/throttlebody (with a pair of 2540's @ 21psi).

R32 RB25DE is capable of more than 300rwkw, my motor in it's previous car was making 365rwkw through standard 25DE head/manifold/throttlebody (with a pair of 2540's @ 21psi).

Ahh yes it is most definitely.. BUT over 300rwkw the rb25 head tends to make it just that little bit easier.

My own head has a little work done to it (port polish, valve deshroud); comparing to the rb25det head on the same dyno with same turbo mods etc it appears to be making power slightly easier when under 300rwkw. Will be good to see how it goes when pushing over 300.

What cams were you running with that combo? I'm in the process of bolting in a pair of 264 9mm's (see my cam cap scoring possible issue in the forced induction section) :P

Ahh yes it is most definitely.. BUT over 300rwkw the rb25 head tends to make it just that little bit easier.

My own head has a little work done to it (port polish, valve deshroud); comparing to the rb25det head on the same dyno with same turbo mods etc it appears to be making power slightly easier when under 300rwkw. Will be good to see how it goes when pushing over 300.

What cams were you running with that combo? I'm in the process of bolting in a pair of 264 9mm's (see my cam cap scoring possible issue in the forced induction section) :P

252's I think, nothing too serious, valves/springs/etc are all standard but he wouldn't sell me cams with the head so I'm stuck with stock 25DE cams for now :blush:

Was looking into cam upgrade but to go whole hog it's like a 2.5k excercise :P

I'm contemplating seeing if I can get some standard 26 cams reground to suit hydraulic lifters..

i was gonna start another topic but i've started too many already so ill just add a post in here...

have any of you guys had the chance to go through a vehicle inspection with the rb30 bottom ends and what did they say about it being legal or not? do u think i should just grind the 30 number off the motor and restamp rb26 to keep it "legal"?

this issue is the single biggest turn off of doing the conversion. Also the fact if i want over 400hp i really need rods and pistons, were as a rb26 only need a set of forgies and stock rods are good to go to 500hp.

i was gonna start another topic but i've started too many already so ill just add a post in here...

have any of you guys had the chance to go through a vehicle inspection with the rb30 bottom ends and what did they say about it being legal or not? do u think i should just grind the 30 number off the motor and restamp rb26 to keep it "legal"?

this issue is the single biggest turn off of doing the conversion. Also the fact if i want over 400hp i really need rods and pistons, were as a rb26 only need a set of forgies and stock rods are good to go to 500hp.

why not just submit the new engine number to transport?

why not just submit the new engine number to transport?

Hey Shane, its not as easy as that. The rb30 is older (finished production late 80s from memory) than the car (1996) its in so therefore the conversion is illegal in WA (dunno about other states though)

the only way of stating its an rb30 is possibly doing an emmision test which is something not even available to the general public in WA.

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