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I have a 351w which I bought which needs a refresh, and the crank has some major blemishes, if I buy a 3.75 stroker crankshaft and use STOCK 302 pistons and 351w rods would the cr be low enough to run pump gas I know the 393 stroker using 3.85 crank and using 302 pistons need at least a 22cc dish piston using stock 69cc heads. Would the 3.75 crank work to keep the cost down and keep the cr down enough to run pump gas? I know the stock smog heads are a bottleneck but I’m not taking this motor out again and I have to change the crank already so I figured I could put in a stroker if I could if I can keep it cheap enough, it’s for a mud truck I bought for 500$ Not putting much other power adders to it other than camshaft and basic bolt ons.
 

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If you do this the way you are thinking, the compression with a 58cc head will be 10.5 based on the flat top /valve relief piston being .050 below the block deck and using a .040 thick head gasket. "Some" will warn you about having the piston .050 below the deck and losing that much quench. It "could" be prone to detonation. I've never done that particular combination so I can't comment. With an aluminum head I would say no problem as they are FAR less prone to detonation regardless of quench.
"I" would go the 393 and aftermarket dished piston route. At 10.5 you would need -17 and 10-1 would be -20 @ zero piston to deck. Build it once but right.
Randy
 

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I have a 351w which I bought which needs a refresh, and the crank has some major blemishes, if I buy a 3.75 stroker crankshaft and use STOCK 302 pistons and 351w rods would the cr be low enough to run pump gas I know the 393 stroker using 3.85 crank and using 302 pistons need at least a 22cc dish piston using stock 69cc heads. Would the 3.75 crank work to keep the cost down and keep the cr down enough to run pump gas? I know the stock smog heads are a bottleneck but I’m not taking this motor out again and I have to change the crank already so I figured I could put in a stroker if I could if I can keep it cheap enough, it’s for a mud truck I bought for 500$ Not putting much other power adders to it other than camshaft and basic bolt ons.
Atomic,
I too have a 351W, its a 69 with the 9.48 deck height. I've been trying to put all the pieces together. Problem is it was bored to 4.040 and I had pitting in #4 so I had to go to +.060 over. It was either that or sleeve it. So with a 4.060 bore I had to find the right stroker kit, after-market heads, and cam. I spent a LOT of time on the Summit Racing web site. They have a couple invaluable tools to help select the parts you may need including the compression ration calculator and CI tool. A link to it can be found at the end of most of the 351W Aluminum Heads.
Hope this helps.
Rebostar
 
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