2 ms·$10-20,000 for a 400hp electric motor. A gas engine would cost a couple hundred bucks.by dangrossman 13y ago$10-20,000 for a 400hp electric motor. A gas engine would cost a couple hundred bucks.greedo 13y ago$200 for a 400HP car engine... They hyperbole is strong with this one. The last time I had an engine rebuilt (mid 1980s) it was over $1100, and this was for a 67 HP VW Beetle engine.mikeash 13y agoWhere can you get a new 400hp gas engine for a couple hundred bucks?