I have an old Pontiac 389 Drag Motor from the 60's. She has these big 'chrome dome' pistons. Looks like whoever got them, polished the top of the pistons or that's how they came from JE back in the day. If anyone knows anything more about them, let me know. Just thought they were kind of cool:
I'll bet they were polished to relieve stress risers and keep them from carboning up so bad. I have seen pistons with polished tops but have yet to see a set that came that way.
I used to polish the pistons when I built race engines and after awhile I realized they melted and blew up just like the others. If it makes you feel good then go for it but very little gain.
I've heard of this. It's supposed to make available slightly more surface area. Sorta like drag "slicks."
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