That engine had a ton of trick stuff done on it. Huge credit goes out to my in house machinist Willie Blair on that one.
With the big Roots blower on it we wanted to reduce the length of the snout and increase it's diameter. The original BDS drive was designed for street cars and stuck way, way out. By having the crank made shorter and with the BBC diameter we were able to essentially "reverse" the upper pulley, bringing it four inches closer to the block front face and reduced the load on the crank a huge amount. Doing this cost us the normal water pump - we made bungs and run a chassis mounted remote pump.
We also eliminated the spacer on most FE blower intakes used to clear the distributor in an effort to shorten the belt. We extensively modified an MSD billet distributor to shorten it, and made an adapter to use a SBC crab cap.
With a very simple baseline tune that engine was beyond my dyno's capacity - we were mainly looking for info on everything working correctly, not leaking, and sounding OK. Tried a few times and saw measured numbers of over 1000 ft lbs almost as soon as the load came in, and could only get it to "grab" a few times to gather data. Other times it would just steam the impeller & run away and the dyno sheet would print out the words "too fast" at certain RPM - how cool is it to have a dyno sheet that says that
It currently resides in a radical dirt drag truck out in Oregon, where its only been run a couple times. First time out it went middle 3's where the next competitor was like a half second behind....
