Ok, to start off I've never had an engine built so I'm hoping the experienced can help. I've been researching a lot but this is a ton of money I am spending and these decisions are driving me crazy. I have a '67 gto I plan to put a 455 in. I have the block at the machine shop, it is a standard bore '74 block. Here is my plan so far for 500hp 500 torque, street driveable on 93 octane fuel.
Parts planned to be purchased from Butler.
Butler/Ross 468 .030 over 4.210 stroke (or should I go longer?), Eagle forged H beam rods. Eagle cast steal crank. Ross Flat top pistons -8cc, classic race file fit rings, Clevite performance bearings.
Butler/Edelbrock round port heads 87cc chamber, 2.11 1.66, Butler custom grind cam 288/294, duration .050 236/242, lift .521/.540, 112LS, performer rpm intake.
PRW stainless 1.5 rockers.
So what is your question, just the crank? Go with what Butler suggests if they are building it for you. Butler knows how to build a Pontiac engine, so you are in good hands. Expensive, yes, but most Pontiac specific shops are expensive.
Each engine builder has their own suggestions, preferences, and opinions. 500HP & 500TQ is not too hard to achieve with a good 455 build. BUT, going to that level, you will also want to upgrade your driveline -transmission & rear axle, PLUS front disc brakes are a must.
The factory 10-bolt is probably your weakest link at this point, and then the transmission. You will want to add the upper & lower control arm supports so you don't tear up the rear frame. You may have traction issues or wheel-hop, so suspension upgrades may be needed.
So anticipate additional $$$ in driveline and suspension mods at the HP/TQ levels you are shooting for - unless you have already done this.
If you are looking for specific itemized pieces for your build, throw a list at us and we can give you our suggestions/opinions and you can decide from there. We always like to help with an engine build, but know it is going to cost - throw any thoughts of a "budget" out the window.