Dyno with AC on? - Performance Forum

Forum Post / Reply
You must log in before you can post or reply to messages.
Dyno with AC on?
Monday, July 24, 2006 11:14 AM
I realize that most people know how drastically the AC affects our cars (or most 4 cylinders), but I've searched and haven't been able to find any results.

Has anyone ever done dyno runs on a stock J with and without the Air Conditioning running? I know you can really feel the difference while driving, but I've been curious to know what the actual difference is.

I'm mostly curious about 2.4L engines, but of course any of the other engines would be just as interesting.

Has anyone on here ever done this? Know anyone that has?



- Darryl
'02 Z24

Re: Dyno with AC on?
Monday, July 24, 2006 12:57 PM
kinda pointless , since once you hit wide open the a/c kicks off

so you wont get a accurate reading







Re: Dyno with AC on?
Monday, July 24, 2006 1:03 PM
Interesting. I didn't know WOT turned off the AC. It's very rare that I mash the pedal.

I'll have to test that.

Thanks.



- Darryl
'02 Z24
Re: Dyno with AC on?
Monday, July 24, 2006 1:06 PM
i didnt know that either....

all j-bod's, or just newer ones do that?
Re: Dyno with AC on?
Monday, July 24, 2006 1:22 PM
It does not kick off during WOT, as Chris(sweetnessgt), he has proof of this.
Re: Dyno with AC on?
Monday, July 24, 2006 2:50 PM
well ive got 3 cavaliers , a 97 2.4 , 00 2.4 , and 02 eco , my friends 05 redline does the same

all 3 shut the a/c off when you go past 80% throttle if your reading the data in the pcm


if his doesnt shut off he has problems , or has the a/c on recirculate , and is still feeling the cold air because the car is cold inside already

alot of manufactures know that when under heavy throttle , you want full power , for passing hill climbing , and having the a/c on will suck out to much power so they shut it off , tell the tps %age drops down


i live where you can fell the a/c shut off since its 110-120 for daily temps







Re: Dyno with AC on?
Monday, July 24, 2006 2:55 PM
I think Sweetness is going to post up in here, but based on my own opinion, I doubt this on the sole fact that I can feel an extreme difference in the top end while the A/C is on, so I dont know.
Re: Dyno with AC on?
Monday, July 24, 2006 3:04 PM
if you look via hp tuners..... the a/c never acutally disengages....... unless of course you rev passed the point where it will which is like 6500 rpms........ its not based off throttle its based off rpm which anyone with hp tuners can verify this. I will direct shifted into here



Re: Dyno with AC on?
Monday, July 24, 2006 3:10 PM
Could both be right...

There is a setting in the PCM to turn the A/C off after a certain RPM, and to turn it back on under a certain rpm. However, since we don't have ALL the parameters in the ECU yet, there could also be a TPS setting we don't see.





4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!

Re: Dyno with AC on?
Monday, July 24, 2006 3:26 PM
never thought about that......... I was keep thinking that the hp tuners beta is done and over with...... well I may stand corrected then



Re: Dyno with AC on?
Monday, July 24, 2006 3:46 PM
I can be going WOT with the AC on and turn off the AC and feel a burst of power. I know my AC doesnt turn off at WOT.



Silver 2001 2.2l cavalier
Still Under Construction
1/4mile:TBA

Re: Dyno with AC on?
Monday, July 24, 2006 5:39 PM
Just for fun my buddy dyno'd his elantra Gt. Without a/c on: 130 hp. with a/c on it dropped to like 115 hp.

I thought the compressor would turn off too at wot. But he proved that wrong for his car.



Re: Dyno with AC on?
Tuesday, July 25, 2006 6:25 AM
I was driving around last summer (with the stock rims/rubber), and I took off from a stop and stepped on it, put it into second, chirped the tires just a little bit. It felt really sluggish, and I looked over and noticed A/C was on, so I pressed the button, and I guess I was just right in the powerband because it chirped the tires again, but in the middle of the gear.

You don't have to believe it, but it happened...



" To study and not think is a waste. To think and not study is dangerous. "
Re: Dyno with AC on?
Tuesday, July 25, 2006 6:54 AM
I can't remember who it was, but I recall someone posting about this and being surprised that it did NOT shut off.

The A/C SHOULD shut off at either high RPM or WOT, but for some reason it apparently doesn't in our cars.

I don't know this as fact though. I just remember someone posting about it.





Re: Dyno with AC on?
Tuesday, July 25, 2006 7:36 AM
So I guess the question still stands.

How much power is A/C actually stealing?



- Darryl
'02 Z24
Re: Dyno with AC on?
Tuesday, July 25, 2006 9:06 AM
the a/c light it self stays on in the dash even when the computer shuts the a/c


i can say the a/c i think in some cases will stay on through first gear and shut off part way through 2nd , mine did it a the drag strip a few times because i forgot to shut it off , droped my 1/4 times about 1/2 second


my guess is about 25-30 hp







Re: Dyno with AC on?
Tuesday, July 25, 2006 11:37 AM
Way back when, when I had A/C at the track. I left it on a few times, and it did turn off at either WOT or high RPMS.



PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Forum Post / Reply
You must log in before you can post or reply to messages.

 

Start New Topic Advanced Search