My mate in the toolroom in NZ put one in his Jetboat. His arl fella made jetboats and 1 of his mates brought 2 blocks in to be machined to Nascar specs (1 was just in case of mistakes) so he agreed to do it if he could have the other if 2 good ones were produced (he was very confident). Stuck it in a boat that was as big as an MG Midget.
The blokes name was Peter Muff & his engines were called Muff Driver.
The same guy that machined it worked with the some others maintaining and being the pit crew for the PDL Mustang which got banned from the Aus Touring cars in the 70's cos they couldn't beat it. They took it over for an exhibition lap some 25 years later and it's lap time was the 4th fastest of the weekend.