Know nothing of the specifics of the 6.2l crank, but aren’t most heavy duty gas engine cranks forged from the factory. Figured what’s what heavy duty entails. Forged cranks, possibly rods and if your very lucky pistons. Strange that the mustang Kellogg? cranks came forged and ones for a hard working truck would not.
Not necessarily. I will state this as My Option...... If you do a forged rod on a cast crank you have moved the weak link to the crank. With that said, it is a very strong weak link. and with the 6.2 main bolts you will have to have to do something Very Wrong to break a crank. I don't think you can twist one up enough to break the crank with the stock head. I don't think you can blow enough air, to break it either. Again this is MOP. I do think you could "Detonate" break one. If you didn't break the new forged rod first.
My option is you could get 15-19 LBS of boost through the head. But you need the fuel to match. This is based on theory. I have never done a 6.2. Just based on past heads with similar flow numbers.
This would yield 740-800 HP..... Just a guess. My biggest question is why? Just to say you have it? Making a Drag truck? There are a lot of lighter options out there for that and better power plants. Now I see you live out west so with a lot of suspension you could possibly use the ponies, I say do the suspension then build the ponies.
If we are just internet building.... I think my numbers are pretty accurate. You would have to build it. To prove me wrong. LOL