LS1 Based Engine Tech LS1 / LS6 / LS2 / LS3 / LS7 Engine Tech

ac on = loss of horse power?

Thread Tools
 
Search this Thread
 
Old 08-01-2003 | 03:24 PM
  #1  
abcTIGER's Avatar
Thread Starter
Registered User
 
Joined: Jul 2003
Posts: 37
ac on = loss of horse power?

i wanted to know if turning on your ac will make your car go slower.if it does how much horse power will the ac take up
Old 08-01-2003 | 03:35 PM
  #2  
LetMeBurnU's Avatar
Registered User
 
Joined: Jul 2003
Posts: 220
From: BAY-AREA CALI
I dont really know how much Hp the ac takes but every time i drive with the ac on.......it feels a lil bit slower.
Old 08-01-2003 | 03:40 PM
  #3  
02Camaroguy1775's Avatar
Registered User
 
Joined: Jul 2003
Posts: 55
From: the killing fields
Definitley slower... A/C is a huge drain, not sure how much but it feels weird driving with the A/C on.
Old 08-01-2003 | 03:58 PM
  #4  
LS1-Maniac's Avatar
Registered User
 
Joined: Apr 2003
Posts: 147
From: Lexington, KY
The amount of HP lost is negligable. The only thing it does that makes it feel slower is it takes longer to build RPMs due to the extra pull from the ac pulley. I ran almost the exact same time in the 1/8 mile with my ac on as I did with it off. I think most of the loss is in our heads rather than actual HP loss. Kinda like those little free mods that add 1-5 hp that people claim to feel a difference.
Old 08-01-2003 | 04:02 PM
  #5  
danziger's Avatar
Registered User
 
Joined: May 2000
Posts: 501
From: Chesapeake, VA USA
Exclamation

Actually the AC compressor can suck up as much as 15HP! The reason it won't affect 1/4 mile times much is because the computer automatically disengages the compressor clutch at WOT. It still takes a couple of tenths to do and the AC will kick back in once you get out of the throttle.
Old 08-01-2003 | 04:11 PM
  #6  
99blackSS's Avatar
Registered User
 
Joined: Aug 2002
Posts: 1,719
From: Bay Area, CA
Originally posted by danziger
Actually the AC compressor can suck up as much as 15HP! The reason it won't affect 1/4 mile times much is because the computer automatically disengages the compressor clutch at WOT. It still takes a couple of tenths to do and the AC will kick back in once you get out of the throttle.
Thats cool. I like my auto it does everything for me. I slam it and it down shifts and now it appearently turns off the compressor.
Old 08-01-2003 | 05:11 PM
  #7  
ChrisLS1Bird's Avatar
Registered User
 
Joined: Dec 1999
Posts: 303
The AC compressor is disengaged upon WOT in most cars.

A side effect of having the AC on is the extra heat it produces under the hood. It contributes to heatsoak. That's probably the most direct effect on performance.
Old 08-01-2003 | 07:17 PM
  #8  
Antz97ZNJ's Avatar
Registered User
 
Joined: Sep 2000
Posts: 3,224
From: Browns Mills, New Jersey
Ive heard it kills 5-10 hp...like said it cuts off at wot...around town i guess it wouldnt matter but if your racing turn it off...I always had mine off unless very hot..I noticed a power loss
Old 08-01-2003 | 08:18 PM
  #9  
SR71 Blackbird's Avatar
Registered User
 
Joined: May 2000
Posts: 50
From: Thousand Oaks
With the AC on during a wonderful 100 degree day my car feels like a dog. Feels like the compressor zaps 30 rwhp in my car, floored or not. Turning it off then stomping the gas makes a huge difference.
Old 08-01-2003 | 11:55 PM
  #10  
blacknight's Avatar
Registered User
 
Joined: Aug 2002
Posts: 221
From: Mission Viejo, CA
Originally posted by SR71 Blackbird
With the AC on during a wonderful 100 degree day my car feels like a dog. Feels like the compressor zaps 30 rwhp in my car, floored or not. Turning it off then stomping the gas makes a huge difference.
Exact same thing with my car. This is at wot or part throttle. Turn the ac off and go wot again and the power is back. Living in Southern Ca means running the ac 8 months of the yr.
Old 08-02-2003 | 12:22 AM
  #11  
2000TA's Avatar
Registered User
 
Joined: Sep 2002
Posts: 191
From: El Paso, Texas
Even at WOT if you have the ac on and you slam it from a stand still the ac does not kick off right away once your rpm's pick up it will kick off (not sure what RPM level) after that as long as you keep you foot in it it should not kick back in. you RPM's never drop enough. buy you do lose power for the time it takes from stop to the RPM point prob lose 1 to 2 tenths of a second. to play it safr turn the ac off
Old 08-02-2003 | 01:21 AM
  #12  
jd13's Avatar
Registered User
 
Joined: Jul 2002
Posts: 479
From: Clearwater, Florida
because the computer automatically disengages the compressor clutch at WOT

That is true. The AC shuts off soon as it recognizes a WOT. I laugh when people who drive Camaros/Birds use the AC excuse, or anytime they say it. This has been true since the thirdgens I beleive because my IROC switches off the AC at WOT also.

I have actually tested this accidently. I'm in Florida so my AC is constantly on. Many occassions at the track I've forgotten to turn it off. I forget when the lines are short and I'm constantly moving. Anyways, with both cars, I've seen absolutely NO losses at all. MPH is the same.

I can't really attest to daily driving because I rarely go above 2k rpms. Yeah, I'm a grandpa. But yes it is true that the AC does rob a couple ponies.
Old 08-02-2003 | 06:32 AM
  #13  
chuck's Avatar
Registered User
 
Joined: Aug 1998
Posts: 905
Originally posted by SR71 Blackbird
With the AC on during a wonderful 100 degree day my car feels like a dog. Feels like the compressor zaps 30 rwhp in my car, floored or not. Turning it off then stomping the gas makes a huge difference.
The loss of performance probably has more to do with the fact that it is hot enough outside that you have to run the ac than the fact that the ac is on.
Old 08-02-2003 | 08:25 AM
  #14  
danziger's Avatar
Registered User
 
Joined: May 2000
Posts: 501
From: Chesapeake, VA USA
Lightbulb

Like I said earlier, there will still be a delay in the clutch action on the compressor when you "floor" it. This may cost a couple of tenths in a timed run. The reason you don't see people running AC at the track is underhood temps and the possibility of the AC condenser dripping.
Old 08-02-2003 | 12:32 PM
  #15  
SR71 Blackbird's Avatar
Registered User
 
Joined: May 2000
Posts: 50
From: Thousand Oaks
Originally posted by chuck
The loss of performance probably has more to do with the fact that it is hot enough outside that you have to run the ac than the fact that the ac is on.


Nooooo. as stated, I turn off the a/c and my car is faster. Feels like usual. Turn on a/c and, viola, power loss.


Quick Reply: ac on = loss of horse power?



All times are GMT -5. The time now is 06:20 AM.