Neil
Supporter
For Neil in Tuscon, most folks don't go for a Donovan block unless they need to...given the normally excessive power of a D-block and what appears to be at least as tight an engine area as a -40, what exhaust and trans did you opt to use, please?
You may be thinking of the Donovan aluminum blocks that were found in most top fuel dragsters and funny cars; those were patterned after the early Chrysler hemi engines- really big blocks. My Donovan aluminum block is essentially a racing version of a Chevrolet 350 small-block but with displacement increased to 383 cubic inches. This block engine is popular for sprint cars and off-shore boat racing.
My headers are Shoenfeld long-tube stepped headers, 1 7/8" pipes stepped to 2" with a 3.5" dia. collector. My transaxle is a Porsche G50-01 mated with a KEP adapter, aluminum flywheel, clutch, and pressure plate.
Regards, Neil Tucson, AZ