Do you think I can put an H89 head on it?

I'm prepping my replacement A14 block and discover that the deck has been milled. The piston are sticking up 0.025 inch. And the A14 dish pistons have been milled down and now has 0.025" dish. That means the bottom of the shallow dish is level with the block deck, but the rim of the pistons are above the deck. Like flat-tops but with the rim sticking up -- and no valve reliefs.

I'm guessing whoever did it was using an open chamber head. But I don't have any spare open heads except the one on my running sedan. I have H89, GX or H95 swirl-port head -- and with heart-shaped chambers.

0.025 inch = 0.635 mm

Standard head gasket is 1.0 mm thick, I think. That would only leave 4-thousands inch clearance from piston to head. Too little?

Will be too close depenDing on squish Of gasket from my understaning.
Can't the pistons be milled or a thIcker gasket be used

When I 1st saw this I thought a smart ass answer was in order like " get a new motor"

is that the block & pistons I gave you ? I'll take the flat tops back if you cant use them, I do have some 1200 pistons but I'm guessing they're too small, what size are they?

risky for the valves, since you are keeping this engine you best go
the Mazda piston machined down depending on your bore size.
What is your bore size on that engine?

Yes epd, this is that short block you gave me. I hope to use it to get my truck running by Saturday.

The pistons are stamped 0.50, so I assume they are 1/2mm oversize.



I'm not assuming it's a keeper, just wanted to get it running and see how good it is, as it was a used engine. Looks to be recently rebuilt (but sitting in my garage for the last few years).

plasticine will be the only way to see if the valves hit.
Otherwise a 2 headgaskets would be the dodgey fix.

I think the guy who had the car originally was running a Datsun comp GX head on that block, I have his original ad from the Dime Quarterly & he's the guy I got the 4.365 rearend center from plus all those headers & other stuff.So whatever a GX comp head design is seemed to work, maybe that'll help.

BTW - do you have any DCOE idle jets ? Specifically 50 F8's.......

might be alright then with the h89.

Dave, if you call me I'll give you the guys # & you could ask him what he was running on it to confirm. He's a nice guy & I think would be glad to talk to you.