How much HP loss from VA IV AC?

[ohm]

I can't find a thread talking about the horsepower loss from a Vintage Air IV setup. I have a 69 Camaro and am installing a LS3 and am on the fence about the AC. I live near the beach so hardly ever use AC in my daily driver so I wasn't going to install it in my Camaro to save weight and HP. Then I realized I will be going to events/races away from the coast and the wife and kid would probably appreciate AC plus for resale it's probably a good idea. Does anyone have a ball park figure on HP loss from a Vintage Air IV setup? Also what do you think the difference in HP loss when AC is turned on vs when it's turned off?
Thanks,
Richard

[Fras]

Minus 3-5 hp

[dipren443]

Ohm (You do electrical work?),

The loss is related to the mechanical energy needed to drive the pump, i.e. the compressor. I don't have the answer for you, but just do some digging on the losses associated with Sanden compressors in general as that is what Vintage Air uses (Sanden 508 for many Gen IV kits). I too will do some digging later tonight, but I just wanted to help point you in the right direction.

Nick

[Fras]

But keeping the wife happy allows buying more stuff to compensate for the lost HP. ;)

[ohm]

that was quick!!
@Fras: 3-5hp is well worth the trade off. and your second comment is funny as hell.....and true!!
@Nick I'm a lighting programmer in the motion picture industry

Thanks guys!!

[dipren443]

Here is a plot from Sanden on power consumption vs. RPM for an SD7

http://www.sanden.com/originals/images/SD7V16_Performance.pdf

[ohm]

nick
what am I looking at in this graph? Is COP consumption of power in HP?

[Protour_Pinto]

I would have to say if you can afford the kit and have the means to install it I would go for it. I would rather have it and not need it than need it and not have it.

I would rather have a Mac2000 and use it as a par can than have a par can and need a mac2000.

A lot to be said about making your family happy too. If they are uncomfortable they will not want to join in car activities.

[sjaroslo]

Not sure if it was addressed but when the A/C is off, the belt will freewheel on the pulley, so I am led to believe that losses would be negligible.

[ohm]

Steve I always wondered that. Thanks!!

[dipren443]

nick
what am I looking at in this graph? Is COP consumption of power in HP?

On that chart, consumption is measured in kW's (kilowatts)

1 kW = 1.3 hp

1 hp = 0.75 kW

And yes, when the clutch is disengaged, the pulley freewheels basically.