Dude,give ACL Engine Parts a call.
Their in 87 Mitchell St,Maidstone,VIC3012.
Don`t know their Website but I`m sure they will help you.
I can`t find any of my old piston books, must have misplaced them.
Good Luck!

Thanks but what pistons would i put in it. Cant wait to build it Will send some photos when i get a digital camera

yes then,bore it to 76 mm,give it a mild cam,a good exhaust,& tune the carb to suit,& it'll be great.if you can find an overdrive 5 speed,it'll go behind the a12,you'll just have to fabricate a gearbox mount & clearance (that means bash it with a hammer) the transmission tunnel.

I dont wanna go to all the trouble to fit a A14 or A15 in my Datsun 1000. I want my car to be fairly fast but still be economical enough to use daily. So i only want to probably put 1300 pistons in it. Or maybe even not. Please give me a good idea to easily gain a little bit of power for an A12 in my 1000. PS A guy told me a Sunny 5 speed gearbox might bolt straight in to an A12 is this true. Thanks

yes,you can overbore the block to 76 mm easily,but it'll only give you about 1270 cc's.you used to be able to get factory pistons at 76.85 mm which gave 1298 cc's.this was good for an under 1300 cc race car.the a14 not only has a bigger bore,but a longer stroke to get the 1390 cc's.you also have to bore out the litle ends of the conrods to accept the bigger gudgeon pins.i feel it's a good way to get more performance out of the motor,if you can't just get an a14 or a15.

I dont think you could overbore the A12 block to fit the A14 pistons..

Because i think the A14 is bored out and has same stroke as A12..But the A15 has differnt stroke all together :)

Id say go with a A15

Should i bore an A12 engine and put A14 pistons in it??? Thanks