Can Piston from an A14 or A15 fit an A12 engine block?

No. The bore size of an A12/13 is 73mm and the A14/15 is 76mm. The A12A engine has a bore
size of 75mm.

Scott
Davo

Can an A12 bore be honed to fit a piston from an A14/A15??

Boring the A12 3mm to suit the A14 is a very common mod, in fact thats exactly what Datsun did in the 70's to create the giant killing Datto's. For trivias sake the maximum oversized
piston for the 1171cc A12 is 60thou over which gives a capacity of 1221cc. A 76mm bore in an A12 gives a capacity of 1298cc which slots in nicely in the sub 1300cc engine class for
racing. Also the bigger bore helps unshroud the valves for better breathing. Hope this helps.

Even if you bore an A12 motor to fit an A14 piston, The wristpin hole is in the wrong place. I used an A14 block and installed the A12 crank. I had to use the A14 rods. The A14 block has a
12-mm higher deck height. I had to cut the top of the block .170" down to the top of the piston. I was worried about the block deck being too thin but that little turbo motor worked well
and it was a screamer at 9,000 rpms. It sounded like an Indy car. I got about 60,000 miles on it without any major mishaps. The rocker arm bolts stripped and I had to heli-coil them but no
other major problems. I like the big bore/short stroke combination. All of my valve train was from PAECO in Birmingham, Alabama. I am not sure if they are online or not. I will check and
post the results.

Hello all,
Paeco is online now and are at www.quicklink.net/
bham/paeco/home.html They still have some Killer
stuff and are usually under NISMO on comparable parts.
Steve

Dead right, sorry I missed that point about the A14 piston. I was thinking about using was the A13 which is no longer available here in NZ. It's been a while since I used stock
pistons and I'm out of touch. There may be some Nismo pistons sitting on a shelf somewhere in the world the Part No is 12010 MO820. Sorry for causing any confusion.

Dead right, sorry I missed that point about the A14 piston. The piston I was thinking about using was the A13 which is the same dia as the A14 ,but I've just discovered is no longer
available here in NZ. It's been a while since I used stock pistons and I'm out of touch. There may be some Nismo pistons sitting on a shelf somewhere in the world the Part No is
12010 MO820. Sorry for causing any confusion.

Steve,
I can't get that Paeco link to work. Is it correct or is it just me? I tried just www.quicklink.net but that didn't work either. Any other
links to this site?

Eddie

So you are saying I can use the A14 piston with the A14 rods and I will have to cut the top of the A12 block .170" ..... Is there anything else I'm missing or forgeting??? If this
is true then I will be doing it soon on an spare A12 block I just got. Do you guys have any other mods that can be done to the block, cam, or crankshaft??? Thanks this really
helps....