Jahns cast pistons were some of the cheapest on the market back in the ’50s, but their forged pistons were quality pieces, albeit quite heavy pieces. What set Jahns Racing Pistons apart was something that they would do that nobody else did – sell piston blanks.
Piston blanks allowed you to machine the wrist pin hole to give the compression height your build needed, and cut the ring grooves where you wanted them at the width you wanted. This was in addition to their finished, ready to install pistons, of course, but it was a great option for hot rodders back in the day who were wanting to get a little deeper into engine building, but weren’t ready to make their own pistons.
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