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Ol' Ron · 10-04-2021, 03:52 PM

This bring back allot of early memories. I only built one 296 and it's still running, doesn't burn a drop of oil, because it has a set of auto thermotic pistons, or stock type steel strut pistons. I never found out who made them but they were 4 ring 3/8 by 4 1/8 stroke . i built the engine back in the early 90 and sold it to Ron Harrell, L-100 cam and all. Compression was pretty high at 8.7. I had a ride it and was very impressed with the performance I installed the top 3 rings and fit the pistons with about .002' Clearance. Pistons were quite heavy and I should have cut off the bottom ring land to lighten it some. Ron recently replaced it with a 294 with a Magnusson blower ASSY This makes 235 hP at 4500
Actually, a stock style steel strut piston can be fit with .001" piston to wall clearance and is why they never burn any oil, when properly cared for.
Gramps

10-04-2021, 03:52 PM	#11
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,861	Re: 3/8x3/8 jahns pistons? This bring back allot of early memories. I only built one 296 and it's still running, doesn't burn a drop of oil, because it has a set of auto thermotic pistons, or stock type steel strut pistons. I never found out who made them but they were 4 ring 3/8 by 4 1/8 stroke . i built the engine back in the early 90 and sold it to Ron Harrell, L-100 cam and all. Compression was pretty high at 8.7. I had a ride it and was very impressed with the performance I installed the top 3 rings and fit the pistons with about .002' Clearance. Pistons were quite heavy and I should have cut off the bottom ring land to lighten it some. Ron recently replaced it with a 294 with a Magnusson blower ASSY This makes 235 hP at 4500 Actually, a stock style steel strut piston can be fit with .001" piston to wall clearance and is why they never burn any oil, when properly cared for. Gramps