Question Re: Ventilation/Heat System Plumbing

[t6dpilot]

My 69 hotrod has never had heat or even the blower/air deflector system during my ownership. The sole intent of this build was as a SoCal hotrod lightweight that would rarely, if ever, see cold weather. Having taken the car on many long trips, I have always wanted to have heat and a defroster on those cold mornings/days. Especially since the MW crew seems to schedule some of our trips early and late in the season, this is becoming more of a necessity.

So this past project started with replacing my headers with SSI's and refinishing my flapper boxes (anal, I know). I got into a major case of the "may-as-wells" while I was in there, but that is a story for another time. So I get everything hooked back up and test the operation of the heat. This was the middle of last summer, of course. My system is currently plumbed from the rocker outlet directly to the defroster vents. I was still trying to go the lightweight route without the blower and ventilation system. I figured I could turn the heat on and off just to the windscreen and that would be perfect. Nope, I get heat all the time - even with the lever in the closed position. And yes, I did check the flapper operation.

My question to the community here is basically, what am I missing? Do you need the trunk apparatus to block the excess pressure fed heated air that doesn't escape the system at the flapper boxes? My guess is yes, but I have seen other cars with the heat plumbed directly to the windscreen. Looking for a solution to not install the blower system. Thanks.

[mike curnow]

If the flapper boxes are closed no heat goes into the car.

[csbush]

This is absolutely the wrong way to do it, but since I was never very successful in getting my flapper boxes to close and seal well enough to keep some heat from coming into the car, I just disconnected the hoses from the heat exchangers to the flapper boxes in the Summer.

[Fishcop]

Same car, same climate... I just had heat-pads added to my seats when they were reupholstered