273 Commando Slugs

Double M said
A little trivia from about 40 years ago. With the factory formula S 273 10.5 pistons, they had offset pins. The trick was to swap banks, and turn the piston and rod assemblies backwards. In other words, take 1, 3, 5 and 7 and put them in the 2, 4, 6 and 8 holes, but notch to the rear, not the front. It was suppose to be worth more horsepower and up to 1000 more rpm's, but you might hear piston slap until the motor warmed up, but didn't hurt any parts.

I did this to a couple of motors, and although I didn't quite get 1000 more revs, it definitely up'd the power and never had a problem. The TRW forged replacement pistons (I think they were L2222F) had a centered wrist pink, so the above wouldn't make any difference.

Like I said, just trivia I remembered when I read your post.

Russ.

I read that in a couple of small block books. Mopar motor builders have been reversing pistons for years. It would be interesting to find out who came up with the idea first. Tom Hoover I would bet. I measured the pistons and all came out within .0005 of each other. It will be an easy job for Steve (the machinist). He can bore and hone the cylinders all the same size and I can install the pistons in any bore I need. He was impressed with the quality of the pistons and the machining. It was fun, the piston pins seemed stuck when I took them out of the box but after they warmed up the pins slid back and forth in the pin bores like butter. (very precision machining) This is fun!
Mike

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