ng8264723 There is one thing I left out on the question, YOUR MACHINIST. He can take cheaper parts, do a super job of installing them in a motor with blueprint specs and the motor runs great for years. You can buy top of the line parts and the machinist doesn't know alot about FE motors, so he setups up the specs to Chevy numbers and the motor blows up after 500 miles. 50% is on the parts 50% in the assemblier. The abuse you are going to do with the motor is the bottom line. Drive easy, small cam, granny shifting, 5000 rpm limit. Cast stuff works.
Now lets get real, a motor in a cobra, any cobra is going to see a little hard abuse at some time. Better bolts and studs like ARP help save the motor, not banging the rpm's off the MSD limiter is also a big help. I ran a case crank in my 452 motor and limit to 6,000 rpm. I put a stroker kit in the same motor to 484 with a bigger cam and still limit the motor to 6,000 rpm. For my application, I want 600 ft of torque and couldnot care less about 600HP. I am going with a 498 stroker in my other motor and will limit it to 6,400 rpm. Most guys like big bore, short stroke.
I am not one of them and have lived with long stroke motors and small bore for along time. I don't call a 4.25" bore small with a set of 2.25 intake valves and 1.75 exhaust. @ of the EMC builders 2 won with long stroke motors. It's all about putting the right parts together. I have built both motors on Dynosim and Dyno 2000. I do this even before a started getting the parts for my motors. Rick L. This is IMO