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Does an rb30 bottom end with rb30 crank bolt straight onto an rb25 head?

Im thinkink of strengthening my bootom end as i am about to put a larger turbo in my car.

Does anyone have some feedback on doing this and also is a ihi apexi rx6 turbo a good upgrade for a gts. I can get a brand new one pretty cheap!!

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confak,

I'm pretty sure that it does bolt straight on, but that the oil and water galleries need to be moved. I'm sure someone out there knows for sure. The RB30 won't strenthen the bottom end just by putting it on, you'll have to look at doing things to the crank, pistons and conrods to make it tough. The extra 1/2 litre will make a larger turbo more responsive though.

Remember the RB30 was only put into shit cars, VL Turbo etc, so I can't believe that the bottom end will be too stronger, but I haven't tried it.

See'ya

:burnout:

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Originally posted by GTS-t VSPEC

Remember the RB30 was only put into shit cars, VL Turbo etc, so I can't believe that the bottom end will be too stronger, but I haven't tried it.

[cough] say what ?!? - the RB30 is used in Oz spec R31 Skylines and Nissan MQ Patrol's. Holden bought the RB30 to put in the VL when they realised the 202 (read: boat anchor) couldn't cut it with unleaded fuel. The bottom end of the RB30 is as strong as any of the RB series.

As for the RB25 head, the non-VCT head bolts straight to the RB30 block without mods, but the VCT head requires oil gallery mods.

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only put into shit cars eh. do i detect someone thats been chopped by VL turbos?

R31 = shit car apparently.

SteveL is correct about the non VCT head. This head is found on R32 RB25DE engines (possibly other engines but I dont know)

RB30 bottom end strength: from what i've read the standard bottom end is used regularly in larger hp applications.

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As well as bolting the head on, you need to modify the cambelt idler / tensioner, and you need to modify the ignition system (RB25 runs coil packs). And you need a R33 ECU to run the coil packs.

email the boys at Zoom! ([email protected]) and ask them which issue covered this conversion.

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Now we've started a stupid argument...

Anybody done 400,000km in their RB25 yet ? Hmmmm...when u do let me know, but there are still plenty of R31's driving around that have done that many km using an RB30 engine.

There is a guy on the www.r31skylineclub.com who has a 323kw/rw RB30 turbo (its actually being sold now for 13k - see http://nissanking.cjb.net/).

You might want to check out the r31forums there for some advice, as there are plenty of people who've put Turbo top ends on their RB30's

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ok from the research Ihave done.

unless your going for mega power forget the rb 25/30 unless you can do all the work your self.

the rb26 crank and rods fit in the rb25 and get some forged pistons if you want to run serious boost or just use forgies on the stock bottom end.

con b4 you do any thing fit the rx6 turbo but make sure its suitable for the rb25 and yes they are very good turbos.

get a power fc z32 afm and bigger injectors merli is making 280 rwkw on a stock bottom end rb25 so you can and when it blows then fix it strong but it could last for ages. If tuned welkl and looked after

meggala

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  • 1 month later...

ricknismo,

http://www.r31skylineclub.com/content/articles

Has a artical on a twincam conversion!

http://home.iprimus.com.au/cobra30/twincam.htm

Is another site detailing the conversion! Costs is also included in this one and it goes into much better explanation on using the non VCT head!

MEGA

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