I have a used set of forged pistons and they have holes on the side. They came with plastic plugs for the holes. The guy I got them from didn’t know much about them. I’ve never seen anything like this . Anybody help me out here ?
Dan's 100 percent right.A 409 given it's large bore would,on those "Old Tech" forgings would run a piston/wall clearence of around .016 cold.They were meant for racing only so cold slap wasn't a concern.Those things,like the forgings in the Chrysler Max Wedge engines[.014] grew a lot.I wouldn't even consider running them in any kind of application today.Wall art.I think they were used to take up space in a cold engine with large clearances yet allow the piston to grow in a high heat application without scuffing. Old tech but still think it’s used in some odd ball applications.
I have a used set of forged pistons and they have holes on the side. They came with plastic plugs for the holes. The guy I got them from didn’t know much about them. I’ve never seen anything like this . Anybody help me out here ?
Dan's 100 percent right.A 409 given it's large bore would,on those "Old Tech" forgings would run a piston/wall clearence of around .016 cold.They were meant for racing only so cold slap wasn't a concern.Those things,like the forgings in the Chrysler Max Wedge engines[.014] grew a lot.I wouldn't even consider running them in any kind of application today.Wall art.
Yes today's modern pistons are stronger,lighter,and run much tighter piston/wall clearances than the old stuff did.Example,A N/A W engine for street/strip use on pump gas will be in the .005-.0055 range as opposed to those old tech/material like you have there which will require .015-.017 piston/wall.Wide wall clearences will mean more piston rock,more ring scrub,which means lost power,shorter componant ,engine assemby life.Just not worth fooling with as these engines are too hard to come by.