383
Do Yourself a Favor?Buy a complete Longblock!!!Theres more to this than just buying Parts and throwing them in the Block,by the Time you have the Machine work on the Block done?Clearencing,Boring,Linehoning,Decking,Preping and cleaning.That ritr there will cost a Grand +.Then you you will need a donor block,and your new Parts,they will need to be balanced.
Find a Good Honest Shop in your Area,and spend around 3500.00 for a say 500-525HP Longblock.Bolt on your accessories...........and Let Her EAT!
Later
G 8)
The reason i say this,is i just did a 383 for My S10 Blazer,and have done about a dozen of these in the past.I probably have close to 1800.00 in Mine and i do all my Own Work!!!