Hi
Sounds like piston to bore clearance to high, measure piston at guegon height , make sure piston is on rod correct oil squirter to trust side ,asemable into engine ,bring to tdc and check how much the piston rocks,also make sure the the skirt is not hitting any thing ie crank counter weights
Michael
ote=CalTrumbo;135370]I am posting this thread to see if anyone else has had this problem.
I built two engines using the Jake Lamont book. The first engine failed after about 4 hours of running time (est.). The piston skirts broke off on one side each of the number one and number four pistons (car right-side skirt). I checked the piston cylinder wall clearance and it was 0.005" which is the upper end tolerance. I had the block re-sleeved and built another engine using the same method but left no stone unturned per the book. I used a test day to break in the engine (one to two hours of run time). I followed book here as well. On the track I never exceeded 6400 rpms and started out at 4400 and went up in increments of 1000 rpms for each 30 minutes of running. After getting it home I pulled the pan and once again found pieces of pistons in the pan. I am assuming they are the skirts. I put the pan back on and walked away (that was a month ago!!!).
I am hoping someone else has seen this and can point me in the right direction?[/quote]