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Heater bypass to cut down cabin heat

JDee

Ancient Racer
1,262
1,123
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
So I have deleted the A/C and I typically run with the windows up since the buffeting at 150 mph is just off the charts. With windows down I seriously think it might blow out a hunk of glass and the wind noise is so bad it pretty much blots out the engine noise. I rely on the dash vents to get some air in, but the air comes out of there pretty hot.

Wondering if I put a heater bypass kit on the engine would that cut it down to closer to ambient air temperature? The heat knob is turned off but it still feels like the air coming out of the vents is way hotter than ambient, so I am wondering if there may be some level of circulation of coolant in the heat core all the time? Or is it just engine room heat getting into the air feed for the heater system?

Something like this:https://pbhperformance.com/product/coyote-swap-cooling-system-hot-water-bypass-kit/
 
3,605
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On paper it looks like it might help, in reality, the heater box should be isolated (depending on how much of the A/C paraphernalia you have removed) so I'm thinking it won't help much. One thing to consider from experience, the old L88s Corvettes were stripped for road racing but they kept the heater box so the windshield defroster worked better, not sure if the mustang stuff is routed the same way. You are correct in assuming that your rear window could blow out with the windows down, it's probably a real good idea to mount some straps over it stock car style.
I am also surprised that you are allowed to run windows, although, in IMSA the cars do run windows and an (inadequate) A/C system , but all the drivers run cool suits.
 

JDee

Ancient Racer
1,262
1,123
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
It's just lapping so mostly street cars. I am moving into Open next event as I've outgrown the Advanced group. There's so many cars in A group that I can rarely get a clean lap from catching slower cars.
I've thought about having the defroster still functional, up here in the great white north spring and fall can be real dicey for fogging the windshield.
I left all the A/C inside the dash alone, only took out the pump and condenser and associated plumbing in the engine room. I have this idea that some day I might want to return it to stock but realistically it may be too far gone for that now.
The groups I run with leave it up to the driver if you want windows up or down and most of them are cool with either turn signals or a point by over the roof for passing. So losing my signals at the last event caused a bit of a stir although we all survived unscathed!
So in IMSA do they run an engine powered A/C compressor to cool the cockpit? Never knew that.
 
Wondering if I put a heater bypass kit on the engine would that cut it down to closer to ambient air temperature? The heat knob is turned off but it still feels like the air coming out of the vents is way hotter than ambient, so I am wondering if there may be some level of circulation of coolant in the heat core all the time? Or is it just engine room heat getting into the air feed for the heater system?

Something like this:https://pbhperformance.com/product/coyote-swap-cooling-system-hot-water-bypass-kit/
The pass side head routes its' coolant through the heater core before going back to radiator so the heater core is always hot.
You could just splice it into the return hose (3/4") and route it behind the intake manifold. The hose going from the pass head to heater core already has a 5/16" restrictor in it.
It's also easy enough to use the OEM connectors. Just cut off the aluminum collar and use 3/4" heater heater hose with spring clamps.
 
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