I just got back home in Huntsville because I needed to bring this airplane over 500 ground miles from Canton Il to Huntsville AL: So my options: Uhaul van - easily $1,000 not counting fuel and 'extras' for a one-time, one-way trip. UGH! After refurbishment, the plane has to go to an airport for initial flight testing. Overhanging, small utility trailer - UGH! Expensive wings and fuselage hanging over the edges waiting for entropy to convert it to crumpled, useless parts. Even worse going to the airport when the plane is ready for final assembly and testing. "Free" boat trailer - the photo showed the weeds had grown up obscuring the frame and the well weather beaten wing frames. I can't afford that kind of 'free'. Order a custom trailer - three requests for quote and nothing. Pontoon boat trailer - lots of them in Minnesota and Michigan. The nearest new, Lebanon MO. <YIKES> One used Ebay trailer in Kentucky in a lovely shade of dull red . . . the rust was free . . . some work required including tires. Asking $900 . . . HUH! Baggett's Trailers, Piedmont, AL - $1,650 new 24 ft pontoon boat trailer build in a week with new tires including a spare. Houston, we have a solution: With a few mods, we should be good to go so: The carpet covered boards are 20 ft but pressure treated lumber comes in 2x8x16 ft. So I needed an 8 ft board cut in half and joined to the 16 ft boards. Then flip over so the joint sections stay in tension under load. So the base-boards cover the gap between the carpet covered boards. Some 1x1 shims were added to prevent them from lifting off at speed and vibrating. I tested with both the 1.5L and 1.8L Prius and the 1.8L Prius won: So driving to Canton Il, there was a hit to the MPG: Testing with the 1.5L Prius verified there was no problem with MG1 and MG2 heating even under extended periods of high load. But the 1.5L engine does not handle high-power as efficiently as the 1.8L engine. The 1.8L engine has exhaust gas recirculation that cools peak power temperatures without forcing a rich mixture. In contrast, the 1.5L engine uses mixture enrichment to cool the exhaust gas to protect the catalytic converter (and valves.) So this is what it looked like loaded: The original engine was carried in the rear passenger area of the Prius for a better center of gravity and to avoid overloading the ball and receiver. Also the props, about 50 lbs of papers, exhaust manifolds, and various parts left over. FYI, I am leaning towards buying a purpose-built VW engine that is tested before shipping. As for ZVW30 towing, the bottom line: ~28 MPG @52-53 mph in the rain The alternative was an 8 MPG, Coachman, whose performance is similar to the Uhaul van. So the 500 miles, the ZVW30 tow vehicle, ~20 gallons, $3/gal -> $60. With the Uhaul van, ~65 gallons, $3/gal -> $195. For a car that can not tow anything, the 1.8L Prius did an impressive job of moving my 700 lb airplane on a 24 ft pontoon trailer and 50+ lbs of documentation from Canton Il to Huntsville Al. Yeap, towing with a Prius is impossible . . . can't happen . . . never happened. Next thing you know, someone will claim man can fly! On a serious note, the 1.5L Prius engine can not handle high power settings efficiently. The 1.8L Prius engine can which explains why the same engine is used in the Prius V (aka., Prius wagon.) As for the transmission, I can not find any evidence of a thermal problem but I was testing in 40-45 F, November weather. The only part in mechanical stress would be the torque limiter, a type of clutch plate on the flywheel. It is possible but not proven that this part might suffer slippage and early wear under extensive, tow operation. Effectively it is handling high power operation over an extended period of time. But those driving in mountains would be doing the same thing and I am not aware of mountain operation limitations. Bob Wilson ps. It may be a while before I revisit this thread or messages. Email works better as I'm probably in the shed working on my airplane.