Just a couple of questions...

[97Cavalier]

Ok folks, I've been thinking about a few things since I got my car out of the shop last week to have the a/c repaired to work for the coming summer. Now that I've been driving the car for about a week and have started getting used to the drag that the a/c puts on the engine I'm wondering what I can do to improve this while keeping the use of my a/c.

First off is that I don't use the a/c full time right now. I only use it on the highway portion of my drive to work in the morning as it's not warm enough at 7am to have it on. A couple of mornings have been more humid than the others so I ran it then to keep comfortable.

However, when I do use the a/c I don't keep it on full time. I've gotten to the point that I turn the a/c off if I start up a long hill (a long hill is one that's more than a couple of hundred yards long) so that I'm not lagging behind the speed limit too far and my questions begin here.

1. Does turning the a/c on and off numerous times during a drive hurt the a/c or will it cause it to wear out sooner?

2. Should an a/c have a thermostat that will turn it off and on based on the temperature inside the cabin of the car? Right now, it seems as though my a/c is either on or off based on the short time that I've been using it.

From here, my questions diverge into a few different areas because these are just a few of the stops that my train of thought has made in the last week.

3. Are underdrive pulleys really effective at improving the performance of an engine whether it is under load or not? And by 'under load' I mean having the a/c on at highway speed going uphill through 10 feet of snow both ways without shoes in the middle of summer with a horse trailer hitched up to the back of my car?

Ok so... maybe I exagerated a bit there.

4. Do those adhesive 'vent visor' things work that are supposed to cover the leading edge of the front door window when it's open or are they just designed to keep rain and other funk from coming in through the window if I have it open a bit?

5. What kind of aerodynamic difference would I see between the following items, if any:

a. An aero mod to the front of my car like basjoos uses on his car,
b. An aero mod to the front of my car like AndrewJ and his hatchback
c. An aero mod that just slopes back from the underside of the front bumper to the factory air dam underneath the front end.

To me, option 'a' would be the best but I'm not of a mind to do that to my car yet. I may be kicking myself in the rump for not following in basjoos's mods but I'm a sucker for the appearance of my car right now.

That's it for now folks. I do apprecaite the forums here and the knowledge that is held within them.

Thanks,

Jeff.

[JohnnyGrey]

1. Does turning the a/c on and off numerous times during a drive hurt the a/c or will it cause it to wear out sooner?

No. Actually, it's bad for the AC to not turn on often enough, like over a whole winter. That's probably why GM put the recirculate switch right next to off.

2. Should an a/c have a thermostat that will turn it off and on based on the temperature inside the cabin of the car? Right now, it seems as though my a/c is either on or off based on the short time that I've been using it.

No reason why it couldn't. More upscale cars do this. Other GMs use variable displacement compressors that are never truly turned off, but as far as I know, the Cavalier does not.

3. Are underdrive pulleys really effective at improving the performance of an engine whether it is under load or not? And by 'under load' I mean having the a/c on at highway speed going uphill through 10 feet of snow both ways without shoes in the middle of summer with a horse trailer hitched up to the back of my car?

Actually the underdrive pulley will show the most improvement at light loads. This is because your accesory chain load is a greater percentage of your total load than when you're really on the gas. I wouldn't be shocked to see a 2mpg improvement on the highway from an underdrive pulley.

4. Do those adhesive 'vent visor' things work that are supposed to cover the leading edge of the front door window when it's open or are they just designed to keep rain and other funk from coming in through the window if I have it open a bit?

I think you'd do best not to have these installed.

5. What kind of aerodynamic difference would I see between the following items, if any:

a. An aero mod to the front of my car like basjoos uses on his car,
b. An aero mod to the front of my car like AndrewJ and his hatchback
c. An aero mod that just slopes back from the underside of the front bumper to the factory air dam underneath the front end.

There's a guy here with an 03 Cavalier sedan that's putting down mid to high 50's on the highway. His mods are more serious than what I'd ever do to my Cavalier, and he can't carry any passengers, but his results are very impressive. Quite a few of us on here have Cavaliers, so welcome to the club! The easiest things to do are to remove the mud guards on the front wheelwells. You can do this in about 10 minutes with an allen wrench. Then you can make grill blocks and remove the passenger side wiper arm. I can't tell you exactly how much of an improvment each of these makes though.

[97Cavalier]

Thanks for the info JohnnyGrey, I do appreciate it.