Outer Limits 4x4 Board

MightyMouse wrote:Well now I'm confused.... those who do the calculations ( and seem to know their trade ) say its impractical - yet others claim to be able to frost a V8 intercooler on a 35C day.

That's just about as opposite set of conditions as I can think off.

I'm still struggling with how a small capacity automotive A/C compressor, designed to produce quite small temperature drops can shift so much heat. I'm also wondering how the condenser manages to dissipate this much heat as well

Some yeah or nay from the HVAC pro's ?

Given that engine is a supercharged petrol it's quite a different scenario.

Unless the supercharger clutch is in, you've got no boost and no extra heat. So all your cooling is cooling below ambient.
If you're watching the intake, I'm guessing the vehicle is stationary and it's probably idling.
In which case air flow is low and cooling it enough to get condensation or frost wouldn't be too hard.

But with a diesel you've got two major differences. Firstly a huge amount more airflow (comparable to a similar size petrol with the throttle wide open), secondly a turbo or supercharger is working almost all the time, feeding the engine hot boost.

I'd say the only real way to do this would be to use the aircon system to complement an already setup water/air intercooler.
Have a header tank for the coolant where you can drop in the aircon evaporator.

Though any heat removed from the coolant by the aircon is then going to have to be expelled by the condensor (sitting in front of your radiator), so essentially, you are still using ambient air to remove heat from your cooling water, just you have to transfer the heat through more mediums resulting in more inefficiencies.

Would probably be more effective if you got a big insulated icebox (esky) and filled it with a mixture of anti-freeze and some ice (or even dry ice), then sit a radiator in the ice mixture and run your cooling water through the radiator.
If you still use a radiator out the front to get rid of most of the heat load (as is already proved by the laminova setups matt and awill are doing) the icemixture could bring the cooling water down to some pretty cold temps, and should last long enough to cope with constant loads presented during hill climbs/mud crawl/track use.

Then we'd have to start worrying about things like throttle icing (for those engines that have throttles).

I think this set up depends on application, We have toyed with the idea of running air con through one of our intercooler set ups. But wether it's beneficial or not at full boost is hard to say. It's something we will look at, but it will require fittings and connections to suit. Linking the compressor to coming on boost so you don't get icing.

I think a system that chills an insulated tank of water held in reserve by 2 valves, triggered and released by a pressure switch from coming on boost above a certain point would work best. Or a simpler version, just fill the tank with ice and don't bother with the air con system.

Either way our intercoolers would be most suitable for this.

All of this heat loss is relative to the ambient temperature.

The AC setup we did dropped the intake air by a considerable amount, but it also had a much bigger radiator than you get with your standard A2W barrel type setup that PWR and the like sell.

It worked well, but you needed to be moving. Slow 4WDing would not see much benefit, but then I would have thought the same with all the other intercooler methods?

Maybe you should go an try it. You could also prove some of the more successful race/rally teams wrong.

- David.

Think the effort vs reward is nil for any sustained applications.....

Just do the air/water well and IMO its going to be way more satisfactory.

MightyMouse wrote:Think the effort vs reward is nil for any sustained applications.....

Just do the air/water well and IMO its going to be way more satisfactory.

I agree

move to the north pole??

I just purchased a second hand subaru W2A intercooler for $100 and I'll see how that goes with plain jane water to air. I'd still like to experiment with using gas vapour or air con gas as *Dirty* has mentioned but I don't have enough funds to buy different intercoolers etc to do any tests. Might give the evaporator in a water tank trick ago depending on how big old sigma evaporators are