R34 Rb25det To Rb30 Conversion

[SKYLINE SAMOA]

Hi All,

Posting form Samoa after reading the 300 pages on the RB25 to RB30 conversion and have a few questions if anyone can help out. You see in Samoa there is no one to talk to thus why I joined up.

The 300 page attachment talk mainly about R32 and R33 Skyline but does not mention if the conversion is possible on R34 skyline??

Has anyone out there done this on a R34 Skyline and if so what basically has to be done, how hard is it???

[lachlanw]

excatly the same . only difference between the two is the cas

[Adriano]

The Neo has vastly different combustion chamber size requiring different pistons

[urtwhistle]

Yes it's possible, i finally dropped mine in today. I cant wait to start it!!!!!

[D_Stirls]

The Neo has vastly different combustion chamber size requiring different pistons

What are the CC's of the NEO head.

Are the intake manifolds interchangeable between the R33 and Neo heads?

[fletch rb30]

the 33 inlet manifold will fit the 34 turbo head only. non turbo has smaller ports

[bubba]

Yes it's possible, i finally dropped mine in today. I cant wait to start it!!!!!

Naice! I expect to see some skidz soon

[urtwhistle]

Hey Bubba, don't worry mate I got 3 sets of stockys lined up. 1 set for every month the car has been off the road. you must have a whole warehouse of tyres lined up lol.

I'm wiring it all up tonight/tomm, then trailering it to Malaga on thursday for a new dump and intake. then i can finally start it and tune it. I'm praying for no oil and water leaks.

regards

Chris

[bubba]

Hey Bubba, don't worry mate I got 3 sets of stockys lined up. 1 set for every month the car has been off the road. you must have a whole warehouse of tyres lined up lol.

I'm wiring it all up tonight/tomm, then trailering it to Malaga on thursday for a new dump and intake. then i can finally start it and tune it. I'm praying for no oil and water leaks.

regards

Chris

Ahh nice I've got 6x 235/40/18's and 4x really old/hard 17" semi slicks ready for when mine is going

Good luck dude!

[SKYLINE SAMOA]

excatly the same . only difference between the two is the cas

so if the crank sensor is the only diff, thats not to hard to solve. So basically i buy a rb30 block, o/haul the dam thing and change the pistons if needed and bolt the rb30 block directly onto my rb25det neo head and thats it????

I gather i will need to buy a rb30det block not a rb30de block?

[SKYLINE SAMOA]

Yes it's possible, i finally dropped mine in today. I cant wait to start it!!!!!

thats great to hear, what exactly did you need to do, please note i am running a rb25det r34 with neo head

[urtwhistle]

Hi Josh, i didn't need to do alot of things and I'm running the stock intake. i re drilled the engine mounts, welded the oil VCT oil gallery, rounted an external oil feed to the VCT gallery and rebuilt the motor. not that complicated at all.

regards

Chris

[SKYLINE SAMOA]

Hi Josh, i didn't need to do alot of things and I'm running the stock intake. i re drilled the engine mounts, welded the oil VCT oil gallery, rounted an external oil feed to the VCT gallery and rebuilt the motor. not that complicated at all.

regards

Chris

Hi Chris,

Thanks for that info, did you use a turbo or non turbo RB30 block? Also what was it like after all that hard work? Was there a huge increase in power? Are you running a R34 RB25 DET standard head or the NEO head? Sorry about all the queations but the street drags in Samoa have truned out to be a battle between the american V8's and Jap imports and so far the V8's are winning. Did you put the all expensive forged pistons in the RB30 block along with the forged conrods or just use the std. rb30 pistons?

[fletch rb30]

hi Josh, are you in western or american samoa? I have spent a fair bit of time working in american samoa and its full of v8s!!

I never saw any rb30 cars in either place so i assume you are going to get one from nz?? If you do, get a mate in auckland to pick up standard rings, bearings, water pump, rb26 head gasket from segedins auto parts by the airport http://www.staparts.co.nz/ probly the cheapest place in town for stock stuff.

Should be good for at least 400hp at the wheels. including myself, i know of 4 cars in nz making that power on stock rebuilt bottom end.

Do you know an aluminium welder? if not, it may be cheaper to get buy a bare head at the same time in nz and get it welded and overhauled and sent over with the block.

You just need a stock rb30e bottom end.

I can reccommend hytech engines in manukau for the machining and welding of the block and head. http://www.hytechengines.co.nz/ he has done all of my friends rb30's for a reasonable price and no problems so far.

Edited March 27, 2010 by fletch rb30

[SKYLINE SAMOA]

The Neo has vastly different combustion chamber size requiring different pistons

Hi Adriano,

When you say the NEO head requires different pistons, it this on a std. engine or when changing from a RB25 to RB30 block and using a NEO head.

[SKYLINE SAMOA]

hi Josh, are you in western or american samoa? I have spent a fair bit of time working in american samoa and its full of v8s!!

I never saw any rb30 cars in either place so i assume you are going to get one from nz?? If you do, get a mate in auckland to pick up standard rings, bearings, water pump, rb26 head gasket from segedins auto parts by the airport http://www.staparts.co.nz/ probly the cheapest place in town for stock stuff.

Should be good for at least 400hp at the wheels. including myself, i know of 4 cars in nz making that power on stock rebuilt bottom end.

Do you know an aluminium welder? if not, it may be cheaper to get buy a bare head at the same time in nz and get it welded and overhauled and sent over with the block.

You just need a stock rb30e bottom end.

I can reccommend hytech engines in manukau for the machining and welding of the block and head. http://www.hytechengines.co.nz/ he has done all of my friends rb30's for a reasonable price and no problems so far.

Hi Fletch,

I am in Samoa (aka western Samoa), Since you where probably out this way last we have switched the side of the road that we drive on so the doors have been open for the last 24 months to imports from

Japan, NZ, Aust and Singapore. I picked up my R34 RB25DET NEO in Singapore for around USD$3500. Car is in excellent condition but 4 door and tiptronic auto.

Just to set the story straight basically if I have a RB25 NEO head all I need is a RB30 or RB30e block + rings and bearing basically to o/haul the 2nd hand block and a RB30 water pump.. The aluminium welding that is needed is done to the head or the block. I was under the impression that the head is untouched and the block you need to weld over the VCT and machine it flat again. In regards to the block, why does it have to be machine down, is this because you use the RB25DET piston heads in the RB30 block and use the STD RB30 conrods??

We can do the welding and machining here thus why i asked. I also read on the forum about changing the Crank angle sensor and you mention above a RB26 head gasket not a RB25 gasket??

Thanks for the parts contact in NZ, currenly burning a hole in my pocket buy genuine parts from JAPAN.

[Adriano]

I used ACL rb30et pistons in the 25 NEO/30 i built, it ended up being about 8.8:1. All r34 rb25det's are NEO's. I would read the PDF about the conversion, as it has all the answers to your questions. You need to weld the vct in the head, and weld some extra material on the front water gallery as well whilst you are at it. Then surface grind. The cas makes no difference, as you will use the cas that matches the car adn head and cams which is all NEO. What turbo are you planning on running, as that basically dictates hat internals you require.

[SKYLINE SAMOA]

Hi Fletch,

I am in Samoa (aka western Samoa), Since you where probably out this way last we have switched the side of the road that we drive on so the doors have been open for the last 24 months to imports from

Japan, NZ, Aust and Singapore. I picked up my R34 RB25DET NEO in Singapore for around USD$3500. Car is in excellent condition but 4 door and tiptronic auto.

Just to set the story straight basically if I have a RB25 NEO head all I need is a RB30 or RB30e block + rings and bearing basically to o/haul the 2nd hand block and a RB30 water pump.. The aluminium welding that is needed is done to the head or the block. I was under the impression that the head is untouched and the block you need to weld over the VCT and machine it flat again. In regards to the block, why does it have to be machine down, is this because you use the RB25DET piston heads in the RB30 block and use the STD RB30 conrods??

We can do the welding and machining here thus why i asked. I also read on the forum about changing the Crank angle sensor and you mention above a RB26 head gasket not a RB25 gasket??

Thanks for the parts contact in NZ, currenly burning a hole in my pocket buy genuine parts from JAPAN.

Hi Fletch,

Did you get my reply? Thanks also for the websites, the only thing is that STA parts website does not work

[urtwhistle]

Hi Chris,

Thanks for that info, did you use a turbo or non turbo RB30 block? Also what was it like after all that hard work? Was there a huge increase in power? Are you running a R34 RB25 DET standard head or the NEO head? Sorry about all the queations but the street drags in Samoa have truned out to be a battle between the american V8's and Jap imports and so far the V8's are winning. Did you put the all expensive forged pistons in the RB30 block along with the forged conrods or just use the std. rb30 pistons?

Hi Josh,

I used a turbo Rb30 block, at this stage its running but i haven't driven the car yet so I'm a little unsure. the head was the Rb25 Neo head that came in my R34. i used Hi comp ACL/Ross pistons on balanced stock RB30 rods and a fully balanced motor and fully reconed head with stock cams. I'm not aiming for a dyno queen, as only about 400hp is expected so i never went overboard with expensive jap brand parts. although i still don't have any change from $6k with me doing all the labour.

regards

chris

[KiwiRS4T]

You can use a non turbo block (turbo blocks are rare in NZ).

Try this link:

http://www.staparts.co.nz/

and try this:

post_a277815_rb30_dohc_1_.zip