How much power out of a 348 engine?

The F40's have the same bottom end. Due to the turbocharging they have a system to cool the pistons with oil jets. The stroke of the crank is different and I would bet that the rod length is different as well but the quality and strength of the parts is the same.

 

my 348 turbo makes just shy of 500hp (498 calculated)

 

I thought the bottom end in the F40 was that of the 328..but with higher quality components. The pictures in the F40 engine rebulid thread seem to confrim this, by the casting of the block. The 348 block has a much much different in casting. But please correct if I'm wrong...

 

You are correct that the block is essentially a 328 but as far as the structure of the crankshaft support etc the 348 is the same. From my experience the quality of components in the 328, 348, 288, F40 are the same. It speaks very well for the strength of the basic V8 motors. The only real problem I have seen in the bottom ends of the turbocharged ones is that they stretch out the main webs making them oval. You have to get creative to put everything right and keep the crankshaft centerline in place to prevent problems with the drive gears.

A girdle like the 430 is reported to have would really be the ticket.

 

Koenig has a twin turbo setup that makes 520hp. They do change the pistons, to ones suited for turbo charging. More than likely a lower compression ratio. As for the con rods and crank, I don't think they mess with those.