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Air Conditioning Removal..More HP?


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My 1984 hatch has an air conditioning unit that doesnt work what so ever. If you take it off and get a smaller timing belt would this help the engine run a little better and maybe get some more MPG? I recently looked at a brat that didn't have a unit and it got me to wondering. Im sure someone has thought of this.

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When you say timing belt i assume you mean the air conditioning belt. If you take all that stuff out (compressor, condensor and all the hoses all your doing is cleaning up the engine compartment. I don't know that you'd really be gaining any power cause when your not using the AC all the compressor is doing is spinning freely. Even if you did gain something it would probably be too small for you to notice. I removed my entire AC system out of my old EA81 hatch and i didn't notice a difference in power. It does however clean up the engine compartment a bit and makes it easier to get at the drivers side valve cover when you need to replace gaskets. Thats my .02.

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No diff in power but you are losing about 15 pounds of extra weight! I got lucky when i bought my junkyard engine, someone removed ac and made a bracket for the alternater that is a lot lighter then stock.

 

That will work, appreciate it.

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same hear, no noticeable difference. like they said, the pulley spins freely and the compressor isnt' actually engaged (or shouldn't be). if you want to be sure, remove the belt and make sure the a/c pulley free wheels as it should. if it does then removing it won't do anything. if it's tight then maybe it'll help a teeny bit and keep your belts lasting longer. the a/c pulley can seize or otherwise become tight due to malfunction, this would reduce the belt life and possibly gas mileage performance but isn't normal for an a/c compressor. under normal (most) circumstances there is nothing to gain....like mentioned earlier....a very small (unmeasureable) amount.

 

on some vehicles the a/c kicks in on certain climate control functions...for instance selecting defrost on some models will turn the a/c on to help keep the condensation off the windows. so if you're running your defrost alot, the a/c compressor would be engaging....but not really doing anything and in this case could save you some performance/gas mileage. i don't know if this is an issue on your make/model, it is on the XT6. if it is, disconnect the electrical connector to the compressor to be sure it's never engaging.

 

those are drive belts, accessory belts or serpentine belts. timing belts are another animal, under the plastic covers below the a/c. can't readily see them without removing the covers.

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same hear, no noticeable difference. like they said, the pulley spins freely and the compressor isnt' actually engaged (or shouldn't be). if you want to be sure, remove the belt and make sure the a/c pulley free wheels as it should. if it does then removing it won't do anything. if it's tight then maybe it'll help a teeny bit and keep your belts lasting longer. the a/c pulley can seize or otherwise become tight due to malfunction, this would reduce the belt life and possibly gas mileage performance but isn't normal for an a/c compressor. under normal (most) circumstances there is nothing to gain....like mentioned earlier....a very small (unmeasureable) amount.

 

on some vehicles the a/c kicks in on certain climate control functions...for instance selecting defrost on some models will turn the a/c on to help keep the condensation off the windows. so if you're running your defrost alot, the a/c compressor would be engaging....but not really doing anything and in this case could save you some performance/gas mileage. i don't know if this is an issue on your make/model, it is on the XT6. if it is, disconnect the electrical connector to the compressor to be sure it's never engaging.

 

those are drive belts, accessory belts or serpentine belts. timing belts are another animal, under the plastic covers below the a/c. can't readily see them without removing the covers.

 

Thats the way it is on my Tacoma on how it engages when the defroster is on. All that I know is that when I drag the switch over to A/C nothing happens so my idea is that it is probably like you said, locked up. The only thing that I do use in it is the defroster which has saved my butt already this winter.

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It's probably not locked up, or you'd have smelled the burned rubber long ago. If it's not coming on, there are two common causes: 1. low refrigerant - the system on most cars is designed to not allow the compressor to come on if it's low on refrigerant. That's to save the compressor from burning itself up. My 86 has a low pressure cutoff, but I don't know if your 84 does. 2. bad connection to the AC clutch. The AC clutch is electromagnetic. It's a pulley that freewheels when not engaged with a magnet that engages when energized. Find the single lead from the AC compressor and run 12 volts to it with the engine off. You should hear the clutch click as it engages and click again when you remove power. If it does that, run the engine and connect 12 volts again. If it turns without making too much noise, the probability is that you're just low on refrigerant.

 

The reason the defrost kicks on the AC compressor is that a byproduct of cooling the air is condensation. Condensation removes ambient moisture from the air, which means that with the AC removing moisture from the air going to your defroster, you're sending warm, dry air to clear your windshield.

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My 1984 hatch has an air conditioning unit that doesnt work what so ever. If you take it off and get a smaller timing belt would this help the engine run a little better and maybe get some more MPG?

 

Short answer, yes. For example, I have a '89 DR 5 speed sedan. I took the air off. Quite a few pounds there, compressor, brackets, condensor, hoses, put plastic caps on the lines that exit the firewall. Toss the clutch and flex fan as well. Oh, as a bonus, get a smaller battery. All about weight reduction. One fan belt does fine as well, less drag and it's never come off even @ 7300 R.P.M. Want the radiator out? Two bolts, unhook the rad hoses, sending wires and I have full access to the front of the engine. After two screws for the grille as well. Every little bit does help with these cars.

 

I recently looked at a brat that didn't have a unit and it got me to wondering. Im sure someone has thought of this.

 

If I don't want the AC, why bother with all that stuff? Oh, I used a factory alt. bracket from a non AC car, makes for a good mod.

 

Just my two cents.

 

Doug

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I really appreciate everyone helping me to solve this problem. My conclusion: just leave it on and quit worrying about it. Now I got to focus on replacing the ignition coil that burned out on me in the college parking lot tonight, $ 40 dollars to get towed home pissed me off.

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