.......well, maybe it's not quite that bad, but it sure feels like having the a/c on sucks a bunch of power away from the motor. It's really bad when the Rpm's are really low (idle-3000), but once the pms get over 3000 and some decent boost gets built its not so bad. This is the first summer I've had my mini so I'm just starting to use the A/C a bunch.

Anyone elses R53 mini loose a bunch of power at low rpm's with the ac on? Is that normal?

 

mines the same way....ac on and the go gets considerable slower....a/c off though....weeeeeeeee

 

I notice a very very slight loss in power with the ac on but nothing to write home about. IMO the ac shouldn't put that much of a strain on an engine. Is it possible that the ac compressor pulley isn't moving freely enough when the ac is on? Seems like something is making it work harder than it needs to.

Wish i was somewhere that i could wait this long before needing the ac. Last year we had 100 consecutive days over 100 degrees. This year i've already seen 113 degrees outside.

 

Take off from a stop is significantly impeded by having the A/C on; but like Ian said, it gets a sudden "shot in the arm" once past ~3k.

If I need a quick take-off, I turn it off, then back on once I'm up to speed.

 

I do the exact same thing....glad I'm not the only one

 

according to constant mpg read out, when cruising at speed i get 2-4 more mpgs with the ac off.

Dont these cars have a kill switch built in for the compressor whenever your at wot....?

 

I believe that is correct.

 

I live in a land of 100 degree summers and the loss in power with AC on and the intense heat really kills the power. I run methanol injection which helps accelerating but not from a dead stop.

I believe this is one of the few cars that does not shut off the AC under heavy throttle. I had a few mazdas before the mini and you could feel the air get momentarily warmer when you mashed the go pedal. It's on my list of things to do at some point to make a little circuit to disable the AC compressor above a certain throttle position. That should help a lot with the loss of power at least while accelerating.

 

I have heard that adding a CAI will fix the problem. I haven't done this myself but have considered it.

 

I have a CAI, 15% pulley, 1" smaller tires that are 10 lbs lighter per corner and it' still a dog from a dead stop.

 

I installed a CAI and Sprint Booster, it's way better than it was. I don't know which helped the most, probably the SB. I used to nearly stall on takeoff, now I barely need to give it any extra throttle at all.

 

I noticed that too, but after installing JCW 380 Injectors and having the DME flashed with JCW software it was no longer an issue.

Sprint Booster or a D-Spec1 module is a good idea too.

 

I just installed an Alta 2% pulley and it made a noticeable difference in the low end pick up. Not sure if it's the 2% overdrive or the fact it's 6lbs lighter than the stock unit. My idle also smoothed out especially with the AC on. All in all a great mod and inexpensive to boot.