gmcjetpilot
Well Known Member
Hot Weather Remove (Temporarily) Cabin Heat & Does Cabin Heat Reduce Engine Cooling?
Envision the cabin heat system:
> High Pressure Air is removed from the high pressure side of the engine baffle
> Air routed to a heat muff wrapped around an exhaust pipe by flex hose
> Hot air out of heat muff routed to firewall mounted air-box on firewall by flex hose
When cabin heat in use that hot air goes into cabin. However when not in use that hot air is dumped into the lower cowl area near firewall which may affect cooling. One you are pulling air from the upper engine plenum and you are pressurizing the lower pressure bottom of the cowl.
Q: Do you disable/remove cabin heat in summer time? Yes or No
(block the air from the upper baffling, remove heat muff)
Q: Have you observed better engine cooling by bypassing the cabin heat system in summer? Yes or No
(theory - pumping high pressure air in lower cowl reduces pressure differential across the engine cylinders)
Q: Do you guess dumping cabin heat in lower cowl reduces engine cooling because of less pressure differential reducing air flow across cylinders? Yes or No
NOTE: Common wisdom is if you block/remove cold feed air to the heat muff remove the heat muff, or you could cook your pipe and heat muff.
Envision the cabin heat system:
> High Pressure Air is removed from the high pressure side of the engine baffle
> Air routed to a heat muff wrapped around an exhaust pipe by flex hose
> Hot air out of heat muff routed to firewall mounted air-box on firewall by flex hose
When cabin heat in use that hot air goes into cabin. However when not in use that hot air is dumped into the lower cowl area near firewall which may affect cooling. One you are pulling air from the upper engine plenum and you are pressurizing the lower pressure bottom of the cowl.
Q: Do you disable/remove cabin heat in summer time? Yes or No
(block the air from the upper baffling, remove heat muff)
Q: Have you observed better engine cooling by bypassing the cabin heat system in summer? Yes or No
(theory - pumping high pressure air in lower cowl reduces pressure differential across the engine cylinders)
Q: Do you guess dumping cabin heat in lower cowl reduces engine cooling because of less pressure differential reducing air flow across cylinders? Yes or No
NOTE: Common wisdom is if you block/remove cold feed air to the heat muff remove the heat muff, or you could cook your pipe and heat muff.
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