What if ?

Is it just me as it really slows the car down far more than I expected. If I'm doing 70 down the motorway and put aircon on, I have to put about another 1" (2.5cm, (in you youngun's language)) on the throttle to maintain speed. I really feel it dive and the tick-over becomes slightly irratic and a bit faster. It noticably affects performance too. The aircon is pretty crap and it seems a bit sacrifce for only a small amount of cold air. Is this normal ?
I have MY05 STI PPP.

dlharris

I think they're all like that. When pulling away, it feels like the handbrake is still on.

LIDDO

Cant say I feel it at all on my MY99 Classic. My old Escort used to slow down when I switched it on but no rev,s drop or anything on the Scoob The only thing i notice, is the juice needle dropping a little faster

Jay m A

iTrader: (2)

If you use boost then it automatically switches the compressoer off, so you will not lose performance when you need it.

You do notice when it kicks in / out though if pootling along, hardly grief though relative to sweating your nadgers off

TonyFlow

Cant say I notice much difference in my MY99 5 Type R either?

kingofturds

iTrader: (1)

bit juddery pottering around town but once i get going dont really notice much difference apart from the fuel gauge

ReggieMY99

cant feel any difference in my MY99 either nor in fuel consumption

HOWY

Anyone know how much of a difference to fuel consumption using air con makes and does it make a difference if you set a slightly higher temperature rather than a very cold one?

nik52wrx

Glad to here i'm not the only one that thinks this. Thought my calipers were
locking on.

kingofturds

iTrader: (1)

not sure but £40 quid to and fro work usually lasts me till the weekend had to fill up again yesterday this week though (had aircon on almost non stop mind you)

rossyboy

iTrader: (8)

I knew there were benefits of living in Aberdeen. My aircon goes on about twice a year Very noticeable decrease in power.

ReggieMY99

well i have to correct myself here


i am missing performance but aint that because hotter air comes through the IC hence i drive moderately when performance is down and so the fuel consumption is also less then if its colder weather

so conclusion is i cant really tell if performance is down because hotter air through IC gives less performance so with the aircon on it equals out somwhere

New_scooby_04

iTrader: (4)

Yep, very possibly! Turbo Engines prefer cold, dense air. The kind of conditions when you'd be inclined to go for the heather rather than the air con!

NS04

What if ?

Gald it's not just me, I was wondering if I should get it looked at. Round town is a but rough and the handbrake quote, how true !! Didn't know it switched off when ragging it, this supprised me as the car definately feels quicker with it off (mybe phsycological)

WRXPete

Really noticed it in the middle of the day last week when the sun was really shining....car was down on performance anyway thanks to the hot air, and the aircon made a noticable difference.....good job it was cruising weather

patkin

MY05 WRX with Climate control can't notice any performance difference on or off but can hear the valve opening and closing. Setting the temp control up will only add warm air to the cold the aircon is still in use just the same.

hades

I think the biggest difference is when pulling away - it's easier to get bogged down with aircon on if you pull away gently. Doesn't make a lot of difference when the turbo is spooled up, even at light throttle/boost to my mind. Doesn't seem to make a lot of difference to fuel economy to me - Monday I got 320 miles on an tank with the aircon doing a fine job for me, and that wasn't all motorway/long journey type stuff. (02WRX with mods)

pmarch

Is that a fact?

I would have thought that with temp set at say 25C (midway) instead of 20C (coldest), the aircon wouldn't have to keep on so long at full blast.

Echo

I get noticable hesitation in a couple of flat spots on the rev counter, 4k and just under 5k with the air con on. I prefer to sweat and have the performance with the air con turned off. It feels like 30bhp goes with it on.

mightyyid

Interesting - my MY05 WRX feels just like it has the handbrake on from anything up to 25-30mph - when running at a constant, say 25mph, the car is almost hesitating rather than running smoothly. I know my MY00 did not do this, so I can only assume they have changed the compressor (quite possible) and this one is not as good. And it makes that noise everytimg the valve open and closes - again, no other cars that we've had with climate control allow you to hear this. Good old Subaru...

New_scooby_04

iTrader: (4)

You should notice it most at lower revs, at 4k you should be on boost, at which point the air con is not drawing any power from the engine IIRC.

NS04

Anders_WR1

iTrader: (8)

I think there's a big performance hit when driving around town, coz the radiator fans kick in a lot and this blows some hot air up through the intercooler. Waterspray was making no noticable difference to performance either.

When I got home the other night, I popped the bonnet and couldn't keep my hand on the interwarmer!

Anders

black scoobs

So im told i belive you lose somthing around 14 bhp when its on .So this may explain why you have slight loss of power.

What if ?

I was playing aroung with the settings yesterday and managed yesterday to get beeter cooling. I set the fan speed to 12 O'clock so it was slower (and quieter) and it cools much better and the car inside temp was nice and cool for once. Tried blowing the turbro a few times up some long hills and the AC does seem to cut out ar the air chill seemed to stop. So in result to my testing, other than being a bit harder to get the car off the mark, once the turbo is on song it seems to have little effect on performance. Round town thoughit is a bit of an irratic pig, but hey, did we buy scoobys to go around town at 20 - 30 MPH ?