ummmm the gas engine comparison doesn't hold water.
What I mean is take that same small block/big block and limit it to 3300rpms.
You'll end up with numbers similiar or below what Hesutton has.
Perhaps a 460 or Fe motor can make 450ft lbs, but the small block has to work pretty hard to get that below 3300rpms.
If this IDI ran up to 6,000 rpms it'd be in the 400hp/400 ft lbs range.
Apples to apples a gas engine would need a different rotating assembly, a different cam, higher flowing heads, larger intake, larger carb, and heavier duty everything to hit 400/400 in a reliable daily driver that could withstand towing and abuse. A conservative estimate including machine work, we're talking $6000-$9000
The IDI hit the these numbers with what? a turbo, an intercooler and a new pump/injectors. At a grand total (brand new) at what $3500? and you NEVER had to open the engine up. No better heads, no machine work etc etc.
Seems like the IDI doesn't do too bad after all.
Typ4, a crazy, totally left field question here.
with the 7.3idi, could we ditch the hydraulic lifters for solid, add double valve springs (or at least dampners), and replace the cam with yours? custom pushrods would probably be needed and oil restriction to the lifters, but we could spin 4500rpms in a much safer manner. The horsepower is already there, we just aren't going far enough to reach it.
Drew