De-Gee,
Been following along. Here are some of my thoughts.
First, THANKYOU for the service given to our country.
I am all for technology. The 4200 has it. Not sure how well it will fit your chassis and think they are ugly. It will present many of it's own challenges.
Back to the 250 or 292.
After just dynoing a 250 with a turbo with the very barest of controls and boost. With 5 PSI and a carb we made 350 hp and equal tq. This was also with a cam not made to turbo. So with the correct planned components IE: cam, intercooler, proper carb , 400 HP would be very doable with the 250.
My dyno 292 in N/A form made 280 hp and always had over 300 tq until higher RPMs. With a turbo expect 400+ ft lbs or more in tq.
For essentials You will need to:
Get Forged pistons made for boost.
rework the stock rods
Balance the lower end
Modify the head with larger valves
Both engines will need:
Turbo
intercooler
blow off valve
wastegate
manifold
EFI computer/ harness
Fuel system
Not sure how the 292 will fit under your hood, check your height.
Just a few thoughts for now. Tom
