Icon IC 743 piston weight incorrect

72DMag said
@nm9stheham Sorry didn't get back to you sooner been away from computer. I see what you mean now. When you said pad of the rod I thought of the small end since alot of guys grind those when doing a stroker.

Actually you have me thinking that I could possibly make the ic743 dome pistons work. I have them boxed but didn't return yet. I think I would need to grind both the top and bottom end though. I would grind the top as pictured above and might get like 20 grams off of it If I had to guess. Then I will grind the big end of the rod to a round shape like pictured. I bet I can get 10 grams off of it which would be 20 total bobweight. Again these are just numbers I am tossing out but that takes off 40 grams and only puts me 31 grams heavier than stock. So it will be close.

I could also use the 18 grams lighter wrist pin but with high compression sounds like a bad idea to me and not going to consider it.

I will be at the shop tmrow and I have some scrap magnum rods I can use for testing. Will measure cap weight by itself too and see what my final weights turn out to be. Thanks!

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I personally would do the lighter pin if you are not leaning on the engine hard. The failure mode described is right, but it takes some loading to get there..... But maybe save that for last.

Glad you have the parts to try. It'll be very interesting to see what you can do. BTW, be aware that almost all of the beam is small end weight. Take a rod and lay it flatwise (like your photo above) and then place it on a thin edge perpendicular to the long axis of the rod. Where the rod balances on the edge will be just above the big end, and when you find that point, everything above that is small end weight, and everything below that (all around the big end) is big end weight. So find that balance point and take careful note of where you are taking the weight off, so you can determine how much bobweight you are actually saving. Remember, you get 1 gram per gram from the small end, and 2 grams per gram from the big end.

If you have an old piston, see how much you can get out by drilling the pin bosses with a few holes. It will not be a lot but that is another spot. There may be some more spots on the pistons. Yeah, I know... you have to be brave to hack into a new set of pistons; just don't put a hole saw through the top LOL, Somehting esle to save for last....

BTW, that rod you show above is a SCAT or Eagle and the material is stronger. So I'd not go that far in material removal.