cold vs. regulated intake air temperature (Thermac), which is better?
#1
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cold vs. regulated intake air temperature (Thermac), which is better?
I have a carbureted (Quadrajet) 350 on my car.
The air cleaner can draw fresh air (cold) or air from over the exhaust manifold (warm). It appears that the mixture of these is controlled by a TVS located inside the air cleaner. This TVS appears to respond to air temperature and looks quite different from most of the TVS units that I am familiar with which respond to coolant temperature and are mounted on the intake manifold.
When the engine (and air-cleaner mounted TVS) is cold, warm air is drawn from over the exhaust manifold. When the air cleaner mounted TVS is hot, cold air is drawn from a fresh air snorkel / system.
It seems reasonable for the Thermac system to use warm air when the engine is cold to speed warmup.
Unfortunately, on my car, the system seems to be continuously adjusting or regulating the temperature of the air, even after the engine is fully warmed up, ususally mixing at least some warmed air with the cold /fresh air.
As I understand things, there are major advantages to using cold air, particularly it's increased density, which can result in improved performance and power.
Is my system malfunctioning or is it designed to work this way to produce more consistent performance and emissions?
If I am interested in maximizing performance, is there some way to set up the Thermac system to work only during engine warmup and then to use only cold/fresh air when the engine is at normal operating temperature?
Thanks for any help.
#2
Re: cold vs. regulated intake air temperature (Thermac), which is better? (rsuddath)
Just as a question, since you are in Cali, do you need the warm air at all? Its not like you will be trying to warm her up in 30 degree temps or anything...
#3
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Re: cold vs. regulated intake air temperature (Thermac), which is better? (rsuddath)
It is designed to try to keep the inlet air. temp. about 100. The vac. can be blocked in warm climates.
:cool:
:cool:
#5
Re: cold vs. regulated intake air temperature (Thermac), which is better? (rsuddath)
I am in Houston and blocked mine where no one can see. To block, I cut the hose running underneath the air cleaner housing and placed a plug between the cut ends. Cold air is good down here.
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Re: cold vs. regulated intake air temperature (Ganey)
Wouldn't you want cold inlet air in ALL climates as long as your engine was already warmed up?
Why regulate at 100 degrees? Can this help performance or economy?
thanks.
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Re: cold vs. regulated intake air temperature (rsuddath)
While colder is better, there are limits- in Alaska in winter a little warming helps. The temp. reg. was for emissions.
#8
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Re: cold vs. regulated intake air temperature (Thermac), which is better? (rsuddath)
the rule of thumb is 1% increase in power for each 10 degree F decrease in intake air temp. In your climate, I'd block it always open.