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Rebuilding my RB25DET..

i have noticed that 5 out of the 6 pistons are number # 1 type and and 1 piston is # 2 type

refering to the manual i found that numbers indicate different bore size and piston to suit

any1 can confirm?

also i am going to be using RB26 Mehle forged pistons... and have been told by many performance shops to leave the bottom end

standard as i dont want much more then 300RWHP....

if i am rebuilding what should i get done? bores are in good condition.

was thinking or pistons/rings/clips, all new RB26 seals/gaskets, get head work 'like skim, valve stem seals, ect' , clean the block and head myself?! and give them a slight hone... n clean?!

i dont know i just want to make sure i do this right

PLEASE help

thanks

GaZ

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Is your motor dead currently?

And why are you using RB26 forgies in a RB25?

300rwhp is totally within the limits of the stock motor. IMO $1400 pistson are a waste of money in it, same with spending any money on the head.

350rwhp is still within the factory motors limits with a good tune.

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Mate just rebuild it to STD specs with a metal

head gasket should be fine.A little tip if you do

rebuild it put the water pump in a bucket of

water while you are doing your rebuild this is

to insure the seal doesn't dry out and leak

once you start the motor up after a period of

time.

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