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420A Piston Balancing

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BLACK'98DSM

5+ Year Contributor
4,450
1,889
Feb 9, 2019
Alabama
So I've been having some thoughts about my engine build and I wanted to share something with you guys. So before I installed my JE pistons, I balanced them. I have a weight scale that measures in grams and I put each piston on the scale. I used a Dremel tool to shave 3 of the pistons to match the weight of the lightest one. In this picture I circled the area where I took material from (I took material from the inside, not the outside, so as to not cause cylinder wall damage).

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I only had to remove 2.5 grams on the heaviest piston, and 1 gram on the next to lightest. I was wondering if this would somehow affect the structural integrity of the piston. Like maybe creating a weak spot for it to break. That seemed like the best spot to remove material from. And I was trying to make the engine as balanced as possible, since I swapped over from a harmonic balancer to an underwrite pulley. And as we know the 420a doesn't have balance shafts like the 4g63 does. I'm basically just 2nd guessing my work. It seemed like a great idea at the time but now I lay back and wonder about it. In reality the pistons will probably outlive the next weakest link of the engine. But I just wanted some opinions and also to share how I kept my built 420a balanced.
 
i'm not sure if the weight of the piston by itself really matters.
wouldn't you want to try and match the reciprocating weight (rod small end, piston, pin, locks, rings).

your all motor so i doubt the piston would break or anything and
its too MF'n late now, its done already, no point in worry'n about it.
 
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