Come on now! The 620 number is wet and full of fuel. Doing the math and pulling the fuel and oil, dropping the reverse, going. Ti and fiber instead of moly, throw a 162 track instead of 174 and your already below 500. I said 460ish and 25-30K. The 460ish number would be a dry number just as the above claims are dry numbers. So I might be 480 for 30K. That is why I left a little wiggle room. With Paul's resources I can get ahold of a cheap nytro bulkhead and apex engine. If someone else were to gather the parts it might be more. It might be less too. I'm not trying to sell sleds here, just saying what could be done. I started with a simple question about the drive and wkr decided to jabb the yammies. When I get a chance I will weigh the sleds like I said I would. Let's see the scale on the carbon fiber units you have. Sounds like your numbers are "ish" as well. Using the smart phone I can't read the scale above. What does it say anyway? BTW, I think you have an awesome build. Not knocking your product, in fact I would love to have one of yours and one of Paul's in my stable!