Originally Posted by Jkingof956
hi am starting to build my 385 stroker build but have a couple of questions that concern me. list of what i have right now:
- 350 sbc 4 bolt main 2 piece rear main seal
- eagle cast 3.75 stroke crank to fit 350 sbc summitracing part #: ESP-103503750
- stock 5.7 rods
- 383 speed pro hypereutectic pistons summit part #: SLP-H859CP40
Question is do i have to do machine work to get the required clrearances? or it should just bolt on ready to go? thanks in advance...
This will not bolt together and go. The typical problems will, especially with stock rods, be rod bolt heads past some cam lobes and cylinder bore extensions into the crankcase often called spigots and the nut end at the pan rail. This takes grinding on the rod bolts and outer shank, the spigots on the pan rail to gain clearance which is generally considered acceptable at .050 inch. And you don't want to go further than absolutly necessary as it is possible to compromise rod strenght and/or get wet by opening into a coolant jacket.
Much of this clearancing and grinding on the rods can be avoided by using an aftermarket rod that closes the rod cap with cap screws that thread into the rod shank. There are Eagle and SCAT rods that are 5140 forgings which are inexpensive that are stronger than GMs 1040 mild steel forgings for little more than a set of rebuit GM pinks. This is a much better way to go, these rods are usually clearanced and if they do need some touching up you're not grinding on the head of a highly stressed bolt. If you use a 12 point headed cap screw that often come with these it usually eliminates having to grind on the pan rail and cylinder spigots as well. You still have to check as the casting process doesn't always result in consistant dimensions, but rods like these solve a lot of problems <<< Small Block Chevy 5140 Steel I-Beam Rods, 5.7 Inch, Press Pin - Speedway Motors, America's Oldest Speed Shop
Since your pistons will take a floating pin which is a much better way to go than pressed (cheap for the OEM to make and assemble) look at this bushed rod which is the same as above except for the small end bushing <<< Small Block Chevy 5140 Steel I-Beam Rods, 5.7 Inch, Bushed Pin - Speedway Motors, America's Oldest Speed Shop
You can get these same design of rods in 4340 for about a hundred buck more.