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Hello all :)

I wont go into too much detail, as its a boring story, but unfortunately I have a crack in my R34 GTT NEO head that cant be repaired. My issue is this, I simply cannot get hold of a replacement anywhere in the UK. So this has got me thinking about the standard RB25DET head, will it fit and work? I know that the neo has VVT and therefore revs higher than the standard head and that the cas wiring is different. But other than that will it work?

Thanks in advance

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https://www.sau.com.au/forums/topic/379447-r34-cylinder-head-cracked/
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Um......not a great idea. The Neo combustion chambers are a different size and the pistons are different as a result. Put an older 25 head on it and the compression should go through the floor.

this. bad idea

I have had the block bored to 87mm and now have Tomei forged pistons and Eagle rods, the pistons have been machined to account for the valve pockets and the compression is good. I am just curious to hear if anyone has done such a thing with the head, as I am a bit stuck. I suppose I could get the head tig welded and run it for a while until a neo head comes available.

As I say, I am a bit stuffed at the moment as I need to come up with a workable solution to my problem of not being able to get a NEO head and as the garage is charging me per day (as whilst my car is in they are loosing money due to my car taking up space)

I guess I could put a R33 GTST head on, swap the internals (other than the lifters) and change the wiring on the cas. But I am just lost and have no idea what to do :(

As above, just tow the car home and buy a neo head or full engine from one of Australia's many wreckers or even off SAU. Plenty of friendly helpful folk on here (who also sometimes happen to have lots of spares haha).

If you can't get any help, i've seen many a people on here offer someone a bit of money to do some shopping/running around and packing/posting. A head shouldn't be hard to ship to the UK.

That's a bit BS about charging you per day because your car is taking up space... must be a really small workshop or something. My car is also at a workshop at the moment, with two engines sitting on their floor and a gearbox plus misc bits. I'm waiting for parts to be made/delivered and they're not charging me any holding fee etc. Not that i did it on purpose though, they pulled the dead motor out then said you need blah blah blah before we feel comfortable putting new motor in.

GL

Where is the crack? Got a picture of it?

I've only ever seen one rb head crack and he was running methanol and 60 pound boost

this

very rare for an RB head to actually crack under normal conditions. are you absolutly sure it is not repairable?

Shipping a head to the UK isn't unfeasible, it won't be that cheap, but it won't be ridiculously expensive either.

If you organise the freight I'm sure a seller wouldn't have an issue shipping it, the issue is finding a neo head, they get snapped up in seconds even here and in Japan where they are readily available.

I would suggest contacting Jesse Streeter and getting one direct from japan, probably your best bet, get the car towed home until you can find one. Also take pictures of the head for us. How did you crack it, run the engine without coolant or something?

Edited by Rolls

I will get some photos as soon as I can, the car will be coming back home this week and with any luck you may look at it and say thats its ok to be tig welded. Unfortunately I dont know how it cracked, plenty of coolant in there. Fingers crossed all will be well.

I will get some photos as soon as I can, the car will be coming back home this week and with any luck you may look at it and say thats its ok to be tig welded. Unfortunately I dont know how it cracked, plenty of coolant in there. Fingers crossed all will be well.

Who told you it can't be fixed? First off take it to a cylinder head shop for a look. If it is a fine crack you can get the head x-rayed. There are specialist welders who can repair most anything these days.

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