SD220 060 Pistons

56-S-Fan........Very informative. Although I don't think I can trust my judgement when looking at these detailed specs like that. I am assuming by your comment that the stepped piston will not work since it is related to the tilt valve setup which is what I was assuming? I will say the guy at Egge put some time in to find me a match and he came up empty even with all of the resources he has. The only lead he has was a Minneapolis Moline tractor piston and they are also non-existent. Something about compression height being the main reason it is hard to find a match. I got the engine builder's total cost to me last night and it will cost me $650 more to sleeve. This route doesn't make any sense at this point because the builder also told me that 1 out of the 6 pistons looks completely different and it weighs 43 grams different. So I will have to buy pistons either way, boring or sleeves. I think I'm just going to bite the bullet and have 060 cast for me which will be cheaper than sleeves. I've been through a dozen people and nobody can find me 060 pistons available. I know there's a set sitting somewhere but how long until that surfaces?

Thanks for all you guys help and resources.

To help clarify, the Silver Diamond series started with flat head pistons, then as Paul wrote, went to stepped head toward the end of that series. The higher-domed tilt-valve pistons did not arrive until '56 or '57 when the head was changed during the Black Diamond series. Stepped and tilt-valve pistons are not the same thing. Flat and stepped pistons are used with the straight-valve head and tilt-valve pistons with the tilt-valve head. This is in addition to the high-altitude and propane pistons.

Dean

If it helps - according to the parts books, the Silver Diamond 220 pistons were flat below engine 261932. The part number for a standard piston was 79 297 R11. Then, during R series production, they switched to the step head piston. Part number 125 875 R11. That's the one that would "drop in". The step head piston was also used in the early straight valve BD 220's. With the change to the tilt valve heads, a wedge head piston was used - part number 172 413 R11. That one would not "drop in" to an SD.

Step head piston

Tilt valve

Dean