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The best RB24 thread on SAU using the RB25 crank is by Legend01...have a read, there is sure to be some good info to help you out.

http://www.skylinesaustralia.com/forums/-t...end01&st=20

He used Arias pistons

cheers matey that is a good help although he looks like his ploud some serious money into that im doing mine on a budget hmm what to do

  • 2 weeks later...

There are ways of building on a budget when you can do most of the labour yourself.

I have found the part no.s for the 4agze pistons only problem is there appears to be 4 different ones mk1-3 and 0.5 overised.

can anyone thats dont the conversion pin point waht ones i need please !!

The cost of gaskets, studs etc in my eyes means instantly no rebuild is budget. Just hope my RB20 lasts long enough for me to get all the parts together over a long enough time frame that i dont realise the large expense that is a built motor

From memory when I looked at using the 4agze pistons the math said they would sit 4mm shy of the deck.

There are ways of building on a budget when you can do most of the labour yourself.

I have found the part no.s for the 4agze pistons only problem is there appears to be 4 different ones mk1-3 and 0.5 overised.

can anyone thats dont the conversion pin point waht ones i need please !!

the early ze pistons were 8:1 and the latest ones (ae101 ze) were 8.9:1.

If you look on club4ag.com forums you should be able to find out all the specs on piston heights etc

  • 3 weeks later...

If you fit the RB25 crank and rods, and use 82mm forged RB20 pistons won't the extra stoke cause the pistons to run proud of the deck, (block) ??

Maybe this is why the 4AGZE pistons are the preferred option??

Sorry to bring this back again but im almost there with the build, the block is at the engineers being rebored to the 4agze 81.5mm pistons :ninja:

I am now struggling to find the right headgasket how do i know what thickness and where do i get an oversized one from ???

Any help greatly appreciated :)

Tomei etc make the headgaskets in bore sizes up to 83mm and various thicknesses. I have 82mm Tomei pistons and they do the associated head gasket for it. I cant help you out with thickness as i am going a different route with the head so mine will be different

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