camp_kilowatt

Applying this guide to a Class C motorhome conversion and the constraints are different enough that I want to ask directly, because I haven't found a good source for motorhome-specific numbers. Weight is my binding variable. My Class C has a GVWR of 14,500 lbs and sits at 11,800 lbs empty — that's 2,700 lbs of payload budget. The diesel drivetrain (engine, transmission, fuel, exhaust) comes out at approximately 1,350–1,400 lbs. So in theory I have roughly 1,350 lbs to work with for motor, controller, battery, and charger combined if I want to come in at or below my original curb weight. In practice the battery will be 70–80% of that budget. Looking at the packs in this thread through that lens: a Tesla Model 3 LFP pack is roughly 1,000 lbs complete. Two Volt Gen 2 packs in a 16S2P arrangement come out closer to 620–640 lbs assembled with cooling plates. The Volt configuration would give me usable headroom; the Model 3 LFP pack would eat almost my entire weight budget before I add the motor. What I can't find is actual completed-build weights for a full motor-plus-controller-plus-ancillaries assembly in the 100–150hp range that's appropriate for a 14,000-lb vehicle. Does anyone have real numbers from a completed build — not spec sheet estimates, but what the scale said when the build was done? That single data point would unlock the rest of my sizing decisions.

Already quoted on the 96V wiring harness for my motorhome build and now reading this thread I'm having serious second thoughts. The efficiency and cable sizing argument for 144V is exactly the kind of thing that doesn't come up until you find it in a build log six months too late.