Air-con removal, before and after power graphs

[Jonff]

Decided to take my car back to EFI parts so I could finally find out if removing the air-con had really gained me any power or if it was purely just a placebo effect. I was pleasantly surprised

Before:

After:

 

[Brett]

Decent gains that. I love to be cool in the summer though...

 

[JamesBryan]

Decent!

Sorted that rattle yet?

 

[Jonff]

Decent gains that. I love to be cool in the summer though...

My air-con didn't work anyway lol

Decent!

Sorted that rattle yet?

Yeah turned out to be the alternator, replaced everything that the aux-belt drives until I'd sorted it though lol

 

[JamesBryan]

Good news mate. It had to be something on the aux-belt like you said, only a matter of time until you found it.

 

[Christopher.]

Need to get rid of mine ASAP

 

[Jonff]

Ayeeee, least everything around that area is fresh now anyway. lol

 

[JamesBryan]

Can get some more trackdays booked now

 

[Fletcher]

Impressive power gains! I have the pure motorsport lightweight AC removal kit sat in the garage waiting to be fitted.

 

[Jonff]

Can get some more trackdays booked now

Me and Rob have spoke about doing one on the 9th April if you fancy that mate? I need to confirm with work that I have that week off though so nothing definite yet.

Impressive power gains! I have the pure motorsport lightweight AC removal kit sat in the garage waiting to be fitted.

Which PMS kit have you gone for mate? The lightweight pulley or the one that uses standard pulleys?

 

[Kelv]

Chop chop then fletch, get it on.

It removes an unnecessary load from the engine, it will allow it to rev a little easier.

 

[Joe#]

Brilliant gains Jon, i bet you're pleased.

I was talking to Rob before about one in April too. I'm game

 

[Jonff]

Brilliant gains Jon, i bet you're pleased.

I was talking to Rob before about one in April too. I'm game

Good stuff mate, it'll be good to see how an RS2'd clio is on track

 

[Fletcher]

Which PMS kit have you gone for mate? The lightweight pulley or the one that uses standard pulleys?

I've got the lightweight kit with the lightweight pulleys etc

Chop chop then fletch, get it on.

It removes an unnecessary load from the engine, it will allow it to rev a little easier.

Yes mate. My 172 has been off the road since last June. I am having the belts changed, and the AC delete kit and matched inlets fitted. Looking forward to getting back on the track with it soon.

 

[Jonff]

I've got the lightweight kit with the lightweight pulleys etc

Ahhh! I went for the standard pulleys version.

 

[JamesBryan]

Me and Rob have spoke about doing one on the 9th April if you fancy that mate? I need to confirm with work that I have that week off though so nothing definite yet.

I'd need to book that day off as it's during the week. I've got one on the Sat 9th March (might have told you about that already).

Will see how it goes and if I don't break anything then I might join you.

 

[Jonff]

I'd need to book that day off as it's during the week. I've got one on the Sat 9th March (might have told you about that already).

Will see how it goes and if I don't break anything then I might join you.

Yeahhh you mentioned that one, with focused events IIRC?

 

[JamesBryan]

Yeahhh you mentioned that one, with focused events IIRC?

Yeah, that's the one. I'm all ready for it now, going to bleed the brakes on the weekend.

 

[Kelv]

Yes mate. My 172 has been off the road since last June. I am having the belts changed, and the AC delete kit and matched inlets fitted. Looking forward to getting back on the track with it soon.

good stuff.
should be fun with a few additions then

 

[Fletcher]

Ahhh! I went for the standard pulleys version.

I very nearly went for that kit mate, but I am trying to make the 172 as light as possible so ended up going for the lightweight kit.

good stuff.
should be fun with a few additions then

I hope so, and add a couple more ponies

 

[yeecup]

Nice gains, iv just got hold of a cup set up off here for my ph1 and also have a nice set of Neil roper matched inlets to fit at the same time so hopefully get a few ponies. Ideally a before rr run would be good to see wha t difference they both make

 

[ben lee]

dont think your power gain is all down to removing the ac.
bet if you had it rr again on the same rollers you would end up with a different result.

 

[Dan519]

dont think your power gain is all down to removing the ac.
bet if you had it rr again on the same rollers you would end up with a different result.

looks like they've used different filtering for the graph on each test. Peak would Likely drop if they filtered the latest runs.

 

[Jonff]

dont think your power gain is all down to removing the ac.
bet if you had it rr again on the same rollers you would end up with a different result.

There might be a slight difference but I doubt they'd be much difference tbh.

looks like they've used different filtering for the graph on each test. Peak would Likely drop if they filtered the latest runs.

Not sure what you mean by "different filtering" as I'm not that clued up on the workings of RRs. Chris wouldn't have done anything to exaggerate the figures though as there's nothing to gain from for it for him. His RR is pretty much bang on with it's results though, I've also seen a few cars make identical power on his RR as they did on Paul's RR at RSTuning.

 

[Martin.]

Can't see the pictures for some reason. Anyone care to share the results with me in text please

 

[Jonff]

Originally it made 173.5bhp and 155lbs ft after I deleted the air-con it made 178.1bhp and 160.8lbs ft

 

[Martin.]

Originally it made 173.5bhp and 155lbs ft after I deleted the air-con it made 178.1bhp and 160.8lbs ft

Awesome result!

 

[bozothenutter]

doesn't the lightweight kit replace the crank pulley aswell?
is that a dampened or non dampened version?

 

[Chip-mk1]

Yeah turned out to be the alternator, replaced everything that the aux-belt drives until I'd sorted it though lol

Is the alternator something that you have also replaced between the two power runs?

As personally I would expect a knackered alternator to cost you more power than an inactive aircon pump (it uses a fair bit of power when you have the aircon on but almost nothing at all when the aircon is turned off)

 

[Jonff]

Is the alternator something that you have also replaced between the two power runs?

As personally I would expect a knackered alternator to cost you more power than an inactive aircon pump (it uses a fair bit of power when you have the aircon on but almost nothing at all when the aircon is turned off)

Yeah I replaced a knackered alternator a few hours before the last run. Uncertain of it's condition during the the 1st run but it was working back then, it was the trackday that I did recently that killed it though

 

[Chip-mk1]

I bet that at most 1bhp of the 5bhp you (maybe) gained was from the removal of the aircon,so all the people excited to do the same and liberate 5bhp too are going to be dissapointed, lol

Just to put it into persepective, what would be getting said IF it was actually losing you 5bhp to have the aircon just idling, is that an entire 50bhp moped engine would stall if you just tried to use it to make the aircon pulley free wheel, LOL

 

[JaredHasNoBrain]

Originally it made 173.5bhp and 155lbs ft after I deleted the air-con it made 178.1bhp and 160.8lbs ft

Nice! Was just about to post and ask cos the pics aint showing on mine

 

[Chip-mk1]

Nice! Was just about to post and ask cos the pics aint showing on mine

Wouldnt take too much notice of it, I can PROMISE you that removing an idling aircon compressor and a tensioner and fitting a shorter belt has NOT gained him 5bhp and it wont gain you it either.


Just to put it into perspective, we are talking about a reduction in parasitic loss here, so what we are looking at basically going to be a saving in friction losses of over 3KW, ie as much heat as a 3 bar electric fire on full chat, the belt/aircon compressor would melt if that was happening!

Different if the aircon was on and working, as obviously then its doing stuff like pumping around refrigerant etc so you will lose a few bhp then, but not just from it sat there idling.

This thread is just a case of some people will believe stuff that they WANT to believe!

 

[Jonff]

Where's the extra power and torque come from then chip? You know a lot more than most on here so I'm interested on what your thoughts are.

The only thing that's changed since the 1st RR run is the aircon delete and the removal of the carbon canister. I can't imagine the engine is still loosening up as it's on 107k

 

[Chip-mk1]

Well a knackered alternator can easily lose you a couple of bhp as the energy is used to break bonds in the metals of the bearings as it continues to break further.
Could easily be a couple of bhp variance just between runs TBH mate, look at the 3 different graphs on your after, for example, surely if the values were always the same they shouldnt vary as much as they do?
Also to me it looks like the first run was done with more smoothing on the dyno, so the settings were different probably, this can take out the peaks and troughs and hence effect the instantaneous peak figures slightly.

 

[ben lee]

thats what i was trying to get at when the ac is of its just like and idler pully. most of the difference will from having it run on different days and rr calibration.

if it was a gain from removing the aircon your new graph power lines would always be above the old power line also a constant 5bhp more from idle to the limiter.

 

[Chip-mk1]

thats what i was trying to get at when the ac is of its just like and idler pully. most of the difference will from having it run on different days and rr calibration.

if it was a gain from removing the aircon your new graph power lines would always be above the old power line also a constant 5bhp more from idle to the limiter.

Actually it would be more likely to be something like a consistant 3lbft from idle to the limiter, as the total loss would always be relative to rpm for that sort of thing, so 5bhp at the limiter but only 1bhp at idle etc.