Re: Collapsed skirts on used pistons

Posted by Jack Vines On 2016/12/17 16:31:34

FWIW, a customer had a numbers-matching 374" block which wouldn't clean at .060". I gave him the options of sleeving the block or having custom forged pistons made up. Either was going to be about $1000.

He was going to teach me a thing or two; so he looked through catalogs for something close to an interchange and came up with Chevrolet 427" tall deck truck pistons and rings for $450. I said, "OK, we'll do it your way. Bore .125" over and hope there are no rust pits inside the water passages, cut .100" off the tops of the Chev pistons, cut retaining clip grooves in the piston pin bores, hone the bushings to size, rebalance the crankshaft. All the machining, plus pistons and rings will be $1200."

We bought the Chev pistons and rings so we could hone to their diameter. Fortunately, we hadn't done the machine work on them, because a rust pit hole opened up in a rear cylinder before we got to .125". We sleeved his block back to .030" and used Egge pistons.

For future reference, should 374" pistons never become available again, it's relatively easy to sleeve a 374" block down to use 352" pistons. As I said, whether to sleeve or use forged pistons is about a wash.

jack vines