Helleluya man thats high comp! then again I just want 10:1.
You will need valve reliefs is you have a high lift cam the Pitroad catalogue and Matsuoka ones have the valve reliefs for that reason.
When I spoke to Mammies they said that the mazda piston combo has too high compression for the road and that they done it. So it must be yours that they told me about. The valve reliefs might take away necessary meat on your pistons needed to relieve stress from the extra heat travelling through weakening the piston.
If you can afford them I would go for the jap pistons in the future made for what we want.
Dam now Im worried about the Pistons Auto Mazda slugs giving ridiculous comp. Well he did say I will have to do my homework but how in the hell can i when Im not an engine builder LOL
If only I could use the a12 rods if the slugs are too tall?

I also use Mazda pistons in my A15, I run 10:1 compression, pistons milled flat, no pockets, F16 cam grind, the engine builder had to deck the top of the block a considerable amount to bring the compression up.

I have a set of new pistons still in their boxes, I'll get the part numbers and post them tonight.

Just to ease everyone's mind, I am not selling the A-13 turbo engine after all. I was offered another coupe so I decided to keep the turbo engine for it. I'm still selling George to my buddy Ray, but he is not getting the turbo engine with it. Is there any other way I can state the fact that I WILL be using the A-12 with ceramic coated everything including .040" over A-14 pistons.
1200rallycar, I'd just like to publically apologize for backing out on my offer to sell the Dimlight Racing UM-1. But, as I said above, I'm keeping that A-series I was going to turbocharge.

I believe my Mazda pistons are E5 pistons. 77.5mm, 23.3mm from top ring land to gudgeon centre (I haven't got a set that haven't had the crown modded).

I still dont know what to do if these pistons are 64mm high and 1mm less than standard?
whats an f16 cam sounds like a fighter jet?

I have been looking at online piston catalogues for suitable oversize pistons for my twin cam project and the two most suitable donor pistons appear to be Mazda B6 and Nissan RB20.

I am particularly interested in the pistons of the turbo versions of these engines, but cannot find a supplier or specs for these.

Does any one know about these?

The pit road site lists pistons up to 79mm for the A15, my current engine has 77.5mm pistons which my engine builder said is as big as I can safely go with my current block,

When we built the engine it was sonic tested to establish wall thickness which my engine builder says needs to be a minimum of .080" (just over 2mm).

How do you guys using bigger pistons get away with it?

Do you just keep trying blocks until you find one with the required bore thickness?

Cheers

Just for some comparisons:

A15.........B6SOHC..........B6DOHC

76mm........78mm..........78mm
30mm........31.4mm.......32mm
65mm........62.1mm.......62.7mm
19mm........20mm..........20mm

Dia,compression height,length,gudgeon dia.

Is it true the A15 block used in Nissan forklift engines has thicker bore walls?

is it true that someone should find out where you can get these forklifts?

seriously, someone give us some info on these nissan forklifts