Flat head pistons

I saw the replies over on the other forum, there are some differing opinions over here. After a lot of reading, I've left that bottom ring out of two engines and am getting ready to on a third. Experts will be along soon.
 
I left 'em off my last build with no ill effects. I did have the assembly balanced that way to make sure.
 
It's been done for years, 4 ring pistons with only 3 rings,
You are not breaking new ground or forging new territory here.

moe
 
I also chop off the bottom of the piston as well. But, You have to be carful here. Most of these pistons are "Auto -thermic" and have a steel strut in them. I make a clamp for the ring area to clamp in the lathe as not to hurt the ring stack. This brings the weight down to to an Egge piston . Now you say "What about balancing" IF ( BIG IF) your using the original crank and rods, not to worry. If not, you have to have it balanced any way.
 
Again it is time for some real facts--it depends on the rings you are using. If you are using the dual scraper oil ring with expander, omitting the 4th ring is completely acceptable or even preferred. If you are using the original type, one piece oil rings it is better to install all 4 of the rings.
 
Thanks everyone for your repies! I couldn't see any reason that they couldn't be run with 3 rings, just needed a little reasurance. Deen
 
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