R34 Cylinder Head Cracked

[andy kain]

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

[zebra]

NEOs use solid lifters.

but the standard r33 rb25 also has VCT

[GTRsean]

Solid lifters in the head as above, and the 05U RB26 rods in the Neo bottom ends allow more RPM's

[GTSBoy]

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.

[JonnoHR31]

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

[andy kain]

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.

[JonnoHR31]

compression will still drop with a r33 head, the chambers are around 15-20% larger

[andy kain]

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

[Adriano]

Tow car home, order head from nissan, will end up cheaper than stuffing around fittingthe worng head. What are they charging you per day out of interest.

[Touge Kyousou]

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

[Gerg_R31]

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

[andy kain]

Thanks for the advice, I can easily trailer the car home, as the garage isn't too far from me. I will put up a wanted thread in the right place for a R34 GTT neo head. Thanks all

[GTSBoy]

Do a search in the for sales here - I think there was actually one or two up for sale recently. Also, look at contacting Jesse Streeter or other buying agents in japan to see what they can find for you.

[Simon-S14]

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?

[KiwiRS4T]

Do some more research and ring around - there's not much that can't be repaired these days - and if you're worried get another Neo head - but I doubt it will be necessary/.

[Rolls]

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 October 10, 2011 by Rolls

[andy kain]

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.

[Simon-S14]

have you had a 2nd opinion?

[Gerg_R31]

I bet its not cracked, if anything a bit of detonation being mistaken for a crack

[KiwiRS4T]

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.