So I spent a little extra to get a super clean low miles 72 Cleveland block, standard bore, (Bill, thanks for the tip on that) for the 408 stroker that I want to build. All the places that I have contacted tell me that the standard piston for the stroker is .30 over.
Does anybody know of a standard bore piston or even .10 over that is dished (closed chamberd heads 64cc) for a 408 stroker (4inch stroke), 6inch rod, That does not have to be special made or won't cost me an arm and a leg?
Because these cylinders tend to be on the thin side, I would like to restrict the bore as much as possible.
Thanks
Jay
Original Post
In my opinion, the heads to use with a 4" stroker are the '71/'72 vintage open chamber Cobra Jet heads. Custom order a set of standard bore forged flat-tops, set the pistons about 0.035" in the hole at TDC for 10.0:1 compression ratio. And don't be mislead in thinking that open chamber heads ping easier than closed chamber heads. They don't.

The advantage to custom ordering the pistons is you can order full round skirt pistons (endurance racing pistons) which are the proper pistons to run in a thin wall block if you want to avoid cracking cylinder walls.

Contact me privately if you'd like contact info for a guy who can spec pistons & rings for that stroker that won't burn oil.

-G
Jay, good idea NOT boring the block. On many, a simple hone-job cleans this up except for the very tops of the bores- which are usually above the ring contact points, so no effect on oil use. I'd suggest forged pistons because -A- they expand a little more than cast or cast-hypereutectics, so a 4.000 forged piston will fit a 4.004" honed bore with only a little noise at start-up, until some heat gets in the pistons & they expand. On my engine, it takes less than a minute. And forged pistons are quite a bit stronger which a stroker will use.
Many stroker cranks these days use 350-Chev rod bearing size, which makes aftermarket 6" Chev rods attractive. Until you realize the Chev wristpin is too big for Cleveland pistons. And Chev pistons have the wrong size valve clearance notches, cut in the wrong places, and modern pistons are contoured underneath the crown, so they can't be trimmed much.
Bottom line: if you are piecing this engine together yourself from parts, you WILL need custom pistons. I also suggest a commercial kit which guarantees you parts that fit with all the details sorted. Sure, it'll cost a few bucks more. But you'll be driving while the piecer-together stroker engine guy is still reading catalogues and spending hours on the phone or web. It's also very possible to wind up with a collection of new parts that don't quite work together.... and have no value to anyone else, so the bucks go down the porcelain convenience.
Great info here guys!!
I much to consider, I am sending the block for clean up and sonic testing
I do have another question
Seeing as I am only looking for 500hp, would I be better off going with a slightly smaller stroke? Say a 393? Would I still be able to get the 500hp? Would this be a better set up?
I do apriciate all your suggestions and thoughts on the matter
Thanks
Jay
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