383 ovrrsize pistons

[unclemike]

I've got a 383 thats been bored 060 already. Bores are slightly scored from running hard and hot. I bought the engine out of a drag car, trw dome pistons, built with alot of clearance. Will need bored to clean it up. Another 010 and its std 440 bore. Anyone know what piston manufacturers make forged std 440 pistons with custom pin height. Chevy big block pistons are available in 070. These would be close to right height, but ridiculous valve notch wont work for 383. Help!

 

[Garys1969RR]

I heard of a guy using 440 pistons in a 383. Just need to get the right C Height, and re balance it. 440 pistons come in alot of different C Heights, from 2.067 down. Your cyl bores will be getting pretty thin. Not good.

 

[wagonman]

Sonic check before spending any $$.

 

[PurpleBeeper]

I've got a 383 thats been bored 060 already. Bores are slightly scored from running hard and hot. I bought the engine out of a drag car, trw dome pistons, built with alot of clearance. Will need bored to clean it up. Another 010 and its std 440 bore. Anyone know what piston manufacturers make forged std 440 pistons with custom pin height. Chevy big block pistons are available in 070. These would be close to right height, but ridiculous valve notch wont work for 383. Help!

Yes, DEFINITELY check your cylinder wall thickness. The general rule of thumb is not to go more than .060" oversize on pistons. If it were me (which it isn't), I'd look for a cheap .030" or .040" oversize 383 block on this website and/or locally & re-use those .060" over pistons.

 

[unclemike]

I heard of a guy using 440 pistons in a 383. Just need to get the right C Height, and re balance it. 440 pistons come in alot of different C Heights, from 2.067 down. Your cyl bores will be getting pretty thin. Not good.

The hard part is finding the pistons I want in std 440 size. All the good pistons are only listed in +.030 or more. Stock cast pistons are too heavy for me. Too bad they dont make std bore stroker pistons for 440. That would allow me to stroke the crank to place the piston even with deck. Will sonic check block first, and if its getting thin, I'll just fill the block and build motor for race only.

 

[BSB67]

Diamond pistons. Start with the 383, 0.060 piston, alter the dia and put the pin where you want it. Done. Won't be cheap.

 

[Garys1969RR]

Looks like you want a 440 piston with 1.755 C Height. That's 1/2 the 383 stroke of 3.38=1.69 plus rod length of 6.535, plus 1.755 C Height =9.98. Deck height of a 383. I don't see any pistons with that c height. It would be much easier to get a 383 block, and bore it to fit your race pistons. I actually have a couple 383 blocks, and I'm in Colo. PM me if int.

 

[BSB67]

Looks like you want a 440 piston with 1.755 C Height. That's 1/2 the 383 stroke of 3.38=1.69 plus rod length of 6.535, plus 1.755 C Height =9.98. Deck height of a 383. I don't see any pistons with that c height. It would be much easier to get a 383 block, and bore it to fit your race pistons. I actually have a couple 383 blocks, and I'm in Colo. PM me if int.

Rod length is 6.358". Piston will need to be in the 1.920 - 1.925 range for zero deck on a cleaned-up deck. There use to be 1.91 and/or 1.94 440 piston (?) but don't know if they are still available. Again, if you buy the right piston as described above, it might cost more up front, but you'll be way ahead in the long run. Adjust as needed for any stroke you're looking for.

 

[Garys1969RR]

Thanks for the 383 rod length info. I have 6.535 in my 383 stroker motor.

 

[BSB67]

Sure. Commonly used chevy rod in B motor strokers

 

[Garys1969RR]

Summit has a Cast piston in std bore of 4.320 and a C Height of 1.912. It's a KB Silvolite, and prob the closest thing you will find in stock. S1276-STD