I believe the pistons are 15cc dish. Calculations are as follows. I believe the difference in compression height between Vitara pistons and A12 is 3.2265mm:

Vitara Pistons - based on 1.2mm standard compressed head gasket thickness

A12 Crank - 70mm Stroke
75mm Bore = 5.87:1 | 1237cc
75.5mm Bore = 5.91:1 | 1254cc
76mm Bore = 5.95:1 | 1270cc

A14 Crank - 77mm stroke (milling pistons to 0 piston deck height)
75mm Bore = 7.9:1 | 1361cc
75.5mm Bore = 7.98:1 | 1379cc
76mm Bore = 8.06:1 | 1397cc

Thinner head gasket (0.8mm?) would raise the comp up around 8.33:1

Standard Datsun Pistons 6cc dish - based on 1.2mm standard compressed head gasket thickness

A12 Crank - 70mm Stroke
75mm Bore = 8.67:1 | 1237cc
75.5mm Bore = 8.77:1 | 1254cc
76mm Bore = 8.85:1 | 1270cc

A14 Crank - 77mm stroke
75mm Bore = 9.44:1 | 1361cc
75.5mm Bore = 9.54:1 | 1379cc
76mm Bore = 9.64:1 | 1397cc

http://honda-tech.com/forced-inductio ... ra-vs-ycp-vitara-2152512/

high comp ycp are a better bet, its the ycp supposedly use a process that makes what they are
http://www.ebay.com/itm/YCP-Pistons-P ... sh=item2c89fa1773&vxp=mtr

Quote:

PS - I don't ever recall saying I was going to put the A14 Crank into my A12 block so not sure where you got this info from?

Or did you assume that because I was enquiring about the A12A rods? I was going this route because I was planning on using forged Pistons and because I was going custom, I thought the bigger pin couldn't hurt. Since decided against forged due to and not required for the result im seeking.

What are the best brand Cast Pistons you can buy to suit an A series? Only ones that seem readily available are Endurotech but I can't say I've heard a great deal about them!

Yep the a12a rods usually are the stroker option, Not sure anything out there aftermarket but usually stock Nissan is stronger. There are some peeps in the past that turboed the A15 with non forgies If I remember right he had a 1000 wagon and was pushing over 20psi with meth/water in a very simple drawthrough setup. To go really cheap you might be able to get some new A15 factory pistons from yahoo auctions and an A14 crank locally for 80-100 aud.

Lags was right though, if all your components are good as they are better just refresh it and start with that to get the ball rolling and gain confidence for perhaps a better prepped bigger A12 stroker bottom end in the future and a cam to suit. Sykines suggestion of e85 I would never look past that.
The only bit I would change is to go oval port h89 head, stock proven to be great for boost and then you wont waste money going from round to oval port.

I've already got the H89 head. Had it for ages! ;)

What's the exact size of the wrist pin on the Vitara pistons? I know A12A rods are 19.7mm. only info I can seem to find is 19mm for the Vitara Pistons. i.e 0.748 inches = 18.9992.

I may have found a set of A12A rods but not sure if they will work?

Don't think those P29 High Comp Pistons are the same as the Vitara's. My research leads me to believe that the ring lands are thin and weak no matter which brand. Vitara pistons have thick ring lands and very strong top design which is why they can take so much power.

They also seem to have too much of a "done" top which would probably raise compression too high even with milling.

yep 19mm (0.7470"), the P29 ringlands look tough to me but dome needs to go
How about getting a cheap A14 bottom end for the crank and pistons?
The A14 have more meat at the tops for milling

Decisions decisions....

Thanks for all the advice.

Keeping this one under wraps for now.

Save your cash and keep the bottom end stock! You'll not notice any difference with all the extra cash you're planning to spend. Use that money to buy a good turbo