I'm rebuilding a 97 351w raptor motor for my 16' jet drive side winder....i'm looking for the correct piston ring gap. that will run at 5000rpm..this is the second motor, as the rings expanded and sized the motor, killing the pistons and block,,,,looking all over the net, i'm getting all sorts of conflicting info,,but i did get this,,,,

At operating temperature, the top ring end gap should be as small as possible. Precise machining of the cylinder bores is critical, and is the reason why rings should be fitted to the cylinder in which they are to be installed. A diameter variance from one cylinder to the next changes the end gap of the rings in that cylinder by a factor of pi (3.1416). For example, a cylinder .001” larger in diameter will increase the ring end gap by .001 x 3.1416 = .003”,
rounding off, which could increase cylinder leakage in that cylinder and decrease performance.

that sounds good

stock piston bore,,stock pistons, STOCK, STOCK STOCK, high lift cam, edelbrock manifold and 600 carb ,lake water cooling
i read that the top ring gap is differant from the second, and the second is differant from the oil rings...what are the stock #s and how much over do i go for the added heat on them

i took the motor to a perfornance rebuilder, had it washed, tanked, and machined,,that was 4 months ago, its not in there records, i did get a tag with the motor saying the bearing sizes to use, but nothing about the ring gap,,,all the info i can find is for cars, not boats, should i go with the circle track figures, as they are running full out,,,4-6000rpm round and round......0,0055 and 0.0057 x bore


,,probly woulnt even get to 5000rpm, but 4800 would be nice,,,,,,,
stock car #s are .016
performance .018
blown racing engines are .024 - .028 .....
.so .023 seems huge
what about .020 sound good,,,,
any thoughts please, and thanks

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