When I bought my '77 10240B AMGeneral in 1993, I paid $4,000 for it since that's all the cash I had. It originally had a 270hp 8V-71 with V730 and 5.57 rears that topped out at 55mph. I traded a '79 GMC Astro cabover with a silver 6V-92TA to my mechanic for him to install Jake brakes, change the rears to 4.56, change the front grease bearings to oil, changed the belt drive radiator fan to gear driven, and change the 12R-22.5 tires to my 11R-24.5's. Then since then I've had the engine overhauled (block bored to straighten the bores and installed over sized liners with standard interiors to use my pistons over again), the engine turbocharged and air to air intercooled with larger injectors, new radiator, additional transmission cooler with fan, larger air cleaner, changed to a turbo muffler, changed the air assist steering to Shepard power steering, replaced all the air bags (
, rebuilt the V730 transmission, rebuilt the alternator, rebuilt the air compressor, new air/water separator, rebuilt the starter. Basically, everything in the engine compartment was rebuilt.
My point? Yes I only spent $4,000 on the original bus. But spent another $35,000 over the years to get it to the point mechanically that I wanted. It will ultimately be better to buy a bus that has the exact power plant you want in it then modifying it. There are numerous already converted buses on the market and also recent 40ft x 102 wide buses-the MCI 102C3 is my favorite. Good Luck, TomC