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Hello all, I have been on the site for a while now but this is my first post really. I currently drive an R34 GTT and live in the UK and I am looking at doing a top mount turbo conversion on my GTT. I have got most of the parts but I still need to find a few final bits and I was wondering if anyone here would be able to help.

My main problem is Forged Pistons, Over here in the UK company’s don’t list any pistons for the R34GTT and the ones that do say they are the same as the R33 GTST but I have also been told by other R34 owners who have put in R33 pistons not to bother because they are different and if I do my engine will last about 6 months before it goes pop. The only other option I have is to get a set fabricated here in the UK which will cost £1000 + VAT which is a lot of money for pistons so does anyone know of any company in Australia or anywhere for that matter that can source R34GTT forged pistons and would be willing to ship them to the UK?

Also having problems sourcing Nismo 740CC top feed injectors it seems in the UK we can only get 540cc for the R34GTT

Thanks in advance also apology’s if I have posted this in the wrong section

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https://www.sau.com.au/forums/topic/161127-r34-gtt-forged-pistons/
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In regards to the injectors

Unless Nismo are making 540cc for the 2007 Nismo range, last time I checked Nismo only made 480cc for the ER34.

The other ones are only available for the R33 series RB25, ie non neo.

Im not sure which highmount your going for, but if its going to be high mounted it will most likely be a large turbo which will make a fair bit of power.

You COULD get away with the 480s but just to be safe I opted for the Sard 650cc which are a straight fit.

As far as i know R34 rb25det pistons are not the same as R33. Neo piston have smaller dome + valve reliefs.

Agreed, but ive never pulled a stock NEO apart. The combustion chambers in the head are much smaller, so the pistons must have a smaller dome to maintain the same compression.

Thanks everyone for the replys some usful information here I will start looking in to them asap. Seems this piston question will go one for ever some say they are the same as the R33 some say they are different. I just dont want to spend 4K on an engine put R33 pistons in and it only lasts 6 months because they are the wrong ones for the car.

Thanks again

Agreed, but ive never pulled a stock NEO apart. The combustion chambers in the head are much smaller, so the pistons must have a smaller dome to maintain the same compression.

I heard this is part of emission thingy... what people usually do is chuck in R33 forgies and increase gasket thickness to 15mm I think...otherwise there'll be high knock

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