How many HP does the AC really steal?
10-02-2007, 12:13 PM
#29
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10-02-2007, 12:53 PM
#30
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10-02-2007, 07:02 PM
#33
I don't buy Kool-Aid
^Yeah me too.
But what if you have the Underdrive Power Pulleys kit that take the wide belt? like the ones that SR claim +12 Would that take more away from your A/C? I men they are 45% lighter than stock pulleys!
But what if you have the Underdrive Power Pulleys kit that take the wide belt? like the ones that SR claim +12 Would that take more away from your A/C? I men they are 45% lighter than stock pulleys!
10-03-2007, 10:07 AM
#34
I just shat myself
This is something I REALLY like about the 8. My 02 Silverado (V6) would loose about 30% of it's power when the compressor was running, while I can only barely notice a difference in the 8.
It's more significant for me because it's dam near always summer in Houston..
It's more significant for me because it's dam near always summer in Houston..
10-03-2007, 10:25 AM
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92 Ford Escort, I did the exact same thing, well without actually naming KITT.
10-08-2007, 03:17 PM
#40
'03 Dodge Viper
07-04-2008, 08:09 AM
#42
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The formula is completely bogus.
An engine might make 232hp at a specfic RPM under full throttle, but it's not doing 17mpg then.
I don't recall what vehicle this was from, but to overcome friction and aerodynamic drag, parasitic losses in the drivetrain and other inefficiency factors, (ie energy made into heat vs maintiaing motion), required something like 15-20hp to keep the car going 55mph.
You can approximate the A/C load by finding it's ratings, often given in BTU's/hr. This is directly convertible to watts and/or horsepower. Then a typical compressor runs at some efficiency, probably pretty high.
Having done that, if it requires 15hp peak x 0.7 duty cycle to run it, I'm betting it won't cut your fuel economy by anything near what would be indicated by using a ratio method to compute. In other words, the ratio method to compute is so oversimplifed as to render it useless.
An engine might make 232hp at a specfic RPM under full throttle, but it's not doing 17mpg then.
I don't recall what vehicle this was from, but to overcome friction and aerodynamic drag, parasitic losses in the drivetrain and other inefficiency factors, (ie energy made into heat vs maintiaing motion), required something like 15-20hp to keep the car going 55mph.
You can approximate the A/C load by finding it's ratings, often given in BTU's/hr. This is directly convertible to watts and/or horsepower. Then a typical compressor runs at some efficiency, probably pretty high.
Having done that, if it requires 15hp peak x 0.7 duty cycle to run it, I'm betting it won't cut your fuel economy by anything near what would be indicated by using a ratio method to compute. In other words, the ratio method to compute is so oversimplifed as to render it useless.
07-04-2008, 07:41 PM
#43
Registered User
Some simple examples of the power required to keep a car moving at a constant rate, and then the energy required to keep it moving at that rate over time.
http://wps.aw.com/wps/media/objects/...cs/topic02.pdf
http://wps.aw.com/wps/media/objects/...cs/topic02.pdf
07-19-2008, 09:20 PM
#47
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I can't believe this thread is still alive.
I was just curious about how much power it takes to actually drive the compressor. not if it's going to slow me down when driving or anything...
I was just curious about how much power it takes to actually drive the compressor. not if it's going to slow me down when driving or anything...
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