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?

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

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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!

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

I was def going to bore the block but was only going to 74mm to keep as much meat between the bores as possible as I'm now using cast internals. I'm at wotk at the moment so can't check what block I have but its a 1976.

Checked all listings for the H-beams and even enquired with the manufacturer. Weirdly they don't offer the 19.7mm pin. They also say you must have a minimum bore size of 76mm which is weird. Apparently their rods were modeled off their engines 75mm size bore even though stock bore is 73mm. This leads me to think they modeled it off one of their A12A's with the 75mm bore but somewhere along the line decided to make the pin 17.45. Strange.

I was only going to go to a 19mm pin if going forged Pistons but have decided to stick with the original plan for the time being and spend the money elsewhere. Might be an upgrade later down the track. Cast should be good for the power I'm trying to achieve.

A set of A12A rods would be nice to have even if they were to sit on the shelf for the time being.

No they were the correct length just don't have the right piston pin diameter. Thought I would put the feelers out to see how available the A12A Rods were.

Was going to go forged but have since decided to keep it simple and keep costs down for now.

Don't the A12A Rods hace more meat around the small end to compensate?

Tried Bprojects already. No good.

No idea what to search on yahoo Japan

I'm in Australia though? I don't believe there were any A12A's here?

I've tried searching around on the net but can't find anything.

Any ideas on how I might be able to get my hands on some?