Can anyone tell me what oversize pistons were available for the 12A. ie: .020";.030"; .040"; .060" ?

A further question on this subject.

How far can the 12A block be bored out? Will they take the 1400 size piston?

I believe an A12A +40 would use an A14 piston

Dattoman,
Thanks for interest and reply.

A standard 1200 piston is 73mm dia. A standard 1400 piston is 76 mm dia.

Fitting a +.040" piston from a standard 73mm does not yield a 76mm bore.

A piston of this size adds slightly over 1.0 mm. to the bore(74mm). That's quite a way from standard 1400 size.

Are you suggesting that the standard 1200 block can be bored out to 1400 size?

Dattoman is talking about an A12a I think you have an a12 where the bore could be different

12a is a rotary ,a12 is our beloved datsun motor

Must be a Freudian thing! I last had a 12 A rotor motor 22 years ago!

I think you get the gist of my query. I'm talking Datto , not the ZoomZoom brand!

fredeuce, so are you talking about an A12 or an A12A? Stock bore is different for each.

The A12 is the one I'm referring to.

you can go 74.5mm bore +060(1.5mm)with no problems.i have some new std 040 or 060 pistons/rings if you interested. where r u located. cheers

Quote:
Any oversize you want. You can order custom pistons from most performance piston manufacturers.

Nissan sells STD, 0.50 and 1.00 (.5 mm and 1 mm oversize).

A12A bore is 75mm... so I was right in that 40 thou gives you the A14 bore of 76 :)