Air gap manifolds in cold weather

I think it would be a good idea to fab up an electrical/coolant-operated heater for the plenum. No other way to get the intake heated up for cold weather. Except, of course, a hot-air induction system similar to what the factory started doing in the '70s. I haven't tried an Air-Gap manifold myself but my 4-bbl. 318 already needs 3-5 min. warmup before I can shift into gear below 50*.