can u bolt a 383 crank made for 5.7" rods into a stock 350 short block and have it work? or would the compression ratio pn the pistons be all wrong?

 

You have to have pistons to go with the stroke.

 

and then u might as well have new rods for the hp too right?

 

Yes, Its a 3.75 stroke crank, but you need to clearance the block. You EDIT: cant use the stock pistons. You can use stock rods but it wont be a true 383. It turns out to like a 377.

 

It's better to buy a "Kit" than try to piece it together if you don't have the experience.

 

well heres what i have now..a forged bottom end 350 and i wanted to just swap out the crank for 250 and have a 383 or 377 or whatever..so would the compression ratio still be fine then w/o changing pistons?

 

or am i better off sticking with the 350 forged bottom with the 847 cam insted oh having to go get a new cam and all since i doubt it will add that much hp with the heads i'm running

 

No. You can't use a 3.75" crank with pistons made for a 3.48" crank. The stock pistons will be pushed 0.135" further up the bores by the longer crank throw, putting them into the head. You need a piston to "match" the longer crank throw.... basically the wrist pin needs to be dropped 0.135".

 

ok, i was thinkong something like that but you'll had me confused for a sec..i'm sticking 350 forged bottom and just spraying it for now..thanks

 

He's right,
I was on a typing spree not reading what I wrote. You can use the stock 5.7 rods but you need new pistons, I dont know why anyone would want to go that route though.
Sorry for the misconseption.