I'm sure most of us in the more southern climes don't bother with interior heat, AC would be more of a concern.
I'm in Canada (eh) where it gets pretty brisk at the start and end of the street rod driving season. My question for others in the more northern areas where a heater makes sense: How did you plumb your heater and manifold heat? How does it work? My plan is to run a hose from the water outlet below the thermostat to the manifold, from there to a T in the heater return hose to the water pump. A separate hose from the water outlet would feed the heater, with a shutoff at the core for warm weather. I'm wondering if the common return hose would have enough capacity for both "circuits" to work well enough.
