Everybody would agree that heat causes the pistons to expand into the cylinder walls. Addressing coolant flow to the rear cylinders helps. Other cooling mods help. Having a good safe tune helps. Not making banzi top speed runs definitly helps. None of these actualy address the fact that a forged piston is very tight to an iron cylinder wall. Bore diameters and piston diameter varies which could result in very tight clearances.
What I'm getting at is alot of people replace their pistons either to avoid this problem or after damage has taken place. I keep seeing that "pistons are the weak link" and "pistons should be on everyones mod list" ect.
I'm wondering if piston replacement is even needed. Would disassembly of the motor having each cylinder torque plate finish honed to match it's individual piston and increase the clearance be a solution? It seems like the pistons themselves are not the week link in the motor, just the clearance. Is there any reason why the pistons themselves can not take the same strain as the rods and crank?
If increased clearance and a new set of rings is all it takes to prevent this you can get off a whole lot cheaper than what larger pistons rings a bore and hone would cost you.
On a related note those of you who have seen your cylinder walls, how much ring ridge is generated at the end of the sweep of the rings in the cylinder???
What I'm getting at is alot of people replace their pistons either to avoid this problem or after damage has taken place. I keep seeing that "pistons are the weak link" and "pistons should be on everyones mod list" ect.
I'm wondering if piston replacement is even needed. Would disassembly of the motor having each cylinder torque plate finish honed to match it's individual piston and increase the clearance be a solution? It seems like the pistons themselves are not the week link in the motor, just the clearance. Is there any reason why the pistons themselves can not take the same strain as the rods and crank?
If increased clearance and a new set of rings is all it takes to prevent this you can get off a whole lot cheaper than what larger pistons rings a bore and hone would cost you.
On a related note those of you who have seen your cylinder walls, how much ring ridge is generated at the end of the sweep of the rings in the cylinder???