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So im rebuilding my motor and have done multiple searches to no avail.

I'm trying to track down part numbers for over sized JE Pistons for my neo motor, but can't find them anywhere.

I'm sure people have rebuilt 25s with JE before. Am i wrong?

Does anyone know the part number or someone who does?

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https://www.sau.com.au/forums/topic/452349-je-pistons-for-neo-rb25det/
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Shouldn't need part numbers - just tell your supplier what you want and they should be able to procure. They may not be in stock anywhere and have to be made to order.

Having said that I haven't seen JE pistons mentioned in a build lately.

Just something to note. Nitto forgies are manufactured by JE. The difference in the piston from Nitto to JE was 1cc in the dome but about $150 difference off the shelf.

HiOctane sold them to me for $1200 I think. maybe $1300

yen the machines I gave my block to said he could get JE cheaper than CP.

Knowing JE is a good brand I agreed, but I also like to do my own research and can't find them anywhere.

I specified multiple times that it is a NEO motor and has different compression ratios, so just hoping he orders the right pistons.

To be honest its hard to find JE for non NEO motors, even the JE website only lists RB26 pistons....

I know of a 3.4L RB26/30 using 87mm JEs and making 800wHP.

they are good.

Also if you're concerned with compression your builder should CC the head and do the calculations prior to even ordering the pistons or a headgasket. you can always ask them; if you're spending that kind of money there don't hesitate to ask as many questions as you need!

yeh but I dont want the stuff around. Much easier to just get the correct piston and comp. Considering it will be much cheaper too. Turns out the the machinist now got a set of ross pistons anyway.

yeh but I dont want the stuff around. Much easier to just get the correct piston and comp. Considering it will be much cheaper too. Turns out the the machinist now got a set of ross pistons anyway.

By doing what was suggested in the post above yours that's how you actually get the correct piston.

yes but i would still rather start off as close to ball park figure as possible with neo specific pistons. This isnt some nuts build, just a freshen up so the less time and money i can sink into it the better.

So I received my ross pistons today to find that they do not have the valve cut outs like the standard ones do.

Anyone have a pic of other after market pistons for neo motor?

Have I been given the wrong pistons?

Part number is 6mkry9603-0.50

Edited by camoo

so basically the compression height is different, the ross pistons are taller from the center of the gudgeon pin, so im guessing that the pistons are for a non neo rb25det.

so basically the compression height is different, the ross pistons are taller from the center of the gudgeon pin, so im guessing that the pistons are for a non neo rb25det.

The stroke on a neo or r33 rb25 are the same (71.7mm) as to the deck height of the blocks so why would the compression height be different? The combustion chamber is 10.5cc,s smaller on Neo. Below rb forged piston to suit neo head

post-64293-0-66723300-1421146166_thumb.jpg

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