But you don't have it all the time, It will warm that water faster than you could imagine, My 5 gallon bed mounted intercooler (Over 8 gallon total volume) goes from ambient (80*) to over 130 with one good hit. With the interchiller it still takes quite a bit of time to bring the temp according to what I found online. Plus the last thing I would want to is to run the AC for 10 minutes or more in the staging lanes trying to get the intercooler temp down to a level that will actually help. The what if you don't have ice argument is lame, That's like saying what if you forgot to get fuel and the track didn't have any lol. If you stop at a gas station/grocery store they are going to have plenty of ice. If you're not smart enough to remember to pick some up you don't belong behind the wheel of a fast car.
What does icing the intake (it does work by the way) have to do with ice in a reservoir ?

 

i relate the icing an intake to using ice in an intercooler. It’s silliness. Extra trouble. If your iat rises that much, something isn’t right. Mine may rise 20 degrees with my air to air and it comes right back down.
it’s not that i can’t remember to pick up ice, it’s just another hassle I wouldn’t want to deal with. I don’t want to remember to fool with that. Regardless of any opinion, the interchiller is a far superior choice. It’s odd you’d think it would slow the car down, you should contact dodge and tell them they made a mistake by doing that with the demon. Let them know that ice is better. Funny thing is that’s one of the fastest production cars, doesn’t seem to slow it down by having the ac on.

 

Exactly how much experience do you have with water cooling intake charges? There is a lot more to it than just turning on the AC and running the car at the track. If you go back and look at my previous posts I stated that it makes sense for the street....so not sure why you're try to prove me wrong when I already stated as much. The thing is the street and the track are completely different if you look further into it you would understand why. Here's a simple break down. Most tracks will not let you run the ac because it will drip on the track, If you pull up to the line and it's dripping water most tracks will back you out and tell you to correct it before you make a run. The water storage in the stock system is small and it isn't taxed like someone doing a burnout and a full drag strip pass, They work on the street but not so well on the track. Adding a larger reservoir will fix that but then you're adding weight plus you have to cool a lot more water and will heat soak the engine/trans right before you make your run. When adding ice you don't have to run the engine at all until you're ready to make your pass.

Tell me what will make more power... A heat soaked engine with an intercooler full of cool water or cool engine with ice cold water?

By the way, Watch some serious drag races like no prep and such and see how many are running AC units versus ice or dry ice, I've haven't seen a single ac compressor on any of them.

 

There is math that can be done to figure out this argument.

How many BTUs can a car AC compressor put out? 5,000 BTUs maybe? How many BTUs does it take to lower 5 gallons of 90* water to 45 degrees?

 

Most serious drag racers don't run an intercooler, they either run M1 and/or get a weight break for not having an IC which often outweighs the gain of having one especially in 1/8th mile racing.

 

Definitely following along as well. I'd love to do this some day. I will probably need something like this AND meth to keep things safe here in AZ. Dealing with 110 temps all summer with no e85 and only 91 octane available will be a challenge.

 

Quite a few no prep cars are but yeah it's far from everyone, On the other hand how many have you seen running an AC unit to cool the intercooler reservoir? I've never seen a single one, Not saying you couldn't find someone doing it if you're looking hard enough.

 

One final time, I hope. Not an all out race car or no prep car. Just a cruiser that can run 9s or 10s, drive to the track, make some runs and drive home.

 

That's even less of a need for an IC to me, you can easily run 9/10's without one. I don't run an IC on my mostly street, sometimes make a pass car. Unless you're going for 200MPH banzai highway runs I don't see the IAT's getting very high on street rips.
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Agree, not many at all run any sort of AC thats for sure.

 

I have done it. I bought a killer chiller for my mustang whatbseems like a life time ago and it works pretty damn well. I will be doing it on my new car when its done. Now your point about ice is well heard for me and that is why my set up as is planned will still allow me to add ice to the system if I am at the track and going all out.

 

Suppose I should have elaborated on the idea more. I've always had it in my mind that the evaporator needs to be inside the reservoir, not simply elsewhere in the loop. So when it is in recovery following a pull, it doesn't just work on removing heat from the small volume that is being pushed through the chiller brick - its working as hard as possible on the bulk of the intercooler water in the tank itself. Not only that, but if you slow pump speed down...it doesn't pick up 'parasitic' heat from the loop as well as trying to cool the IATs when not needed. Then upon some input, like TPS for example, you'd ramp the pump speed in accordingly to flood the IC with cold fluid. Granted in your case with the chiller external to the tank, you have to cycle the fluid to get the reservoir volume chilled. But with the evaporator in the tank this would be possible. Three6GMC actually did the tank-enclosed evaporator and had some awesome results. Fixed pump speed though I believe. This is his tank build.





I agree with you that thermal mass is a thing and it is more beneficial to your immediate IAT to have it pre-chilled. But you don't really need it at the beginning of the pull...its the back half of the track that suffers if you've used all of your heatsink/thermal reserve in the first half of the track when you probably weren't knock limited anyway. I want the chilling effort ramping in harder, but later, so that you keep below the knock threshold when temps start building. Of course you can't do this with manual PWM control unless you want to turn the **** while you drive lol. I used similar load-dependent control with the CWA400 as my primary water pump and was able to manage ECT better than the stock cooling system, all without a thermostat.

I think your temp rise is more than it should be during a pull. I see charge temp performance pretty close to that from mid-range A2A intercoolers on builds with similar mods. With a bit of plumbing reconfiguration, some insulation and maybe a variable pump speed controller...you could likely cut those temps down by 30 degrees or more.

 

This is on line with what I'm thinking about. Evaporator in tank.


Everything in my car is PWMd based on what driving mode the car is in. I like your idea of increasing the flow at top of the track. In my car, along with turning the compressor off, I can see increasing flow based on MPH, in drag mode, or closed loop with the IATs.

I am told the the BMW water pump has a PWM input to control the flow. Gotta look into that.

No reason why the compressor and water pump can't be controlled by closed loop setup. Another cool arduino project.

 

I don't outright recommend anybody do what I've done because it tends to be a scope creep nightmare project lol. But yeah I'm in agreement...model and automate everything.

 

Scope creep?? Me.. never!

I'm the king of scope creep. Check my vette project.

 

Easy enough questions to answer. Let's start with the last question first.

1BTU = energy to raise the temperature of 1 pound (pint) of water 1 degree F. 5 gallons = 40 pints (pounds), * 45 degrees F = 1,800 BTU. But AC is rated in BTU/Hour, so the question is how quickly do you want to chill that water. If you want to chill it in 5 minutes, then that would be 21,600 BTU/hour to do it in 5 minutes.

That's way more than your "guess" at capacity for automotive AC systems. Good thing you were way off on that estimate. Most modern (R134 or newer) automobile AC systems (compressor, evaporator, condenser) operate at between 18,000 BTU/hr and 24,000 BTU/hr (aka 1.5 to 2 ton). Dual evaporator units may be slightly larger than that.

So that goal is not too far out of reach for an average car AC system, if you don't have refrigerant flowing to the evaporator in the HVAC system, and only use the refrigerant to cool the intercooler water.

That may not happen at idle, and the heat load into the condenser (and into the radiator, engine coolant, etc) would be pretty high while the water is chilling. Wich means you'll start the next run with the engine already operating at the high end of your target temperature range.

For the drag strip, ice (with salt if you want it even colder) is a better choice.

 

For comparison, if you put a chill coil like this one in a cooler or box shaped tank, put a block of ice in the middle and added salt and water to fill the tank, the brine in the tank would be at 0°F, how cool the solution in the pipes would be would depend on the flow rate and the material of the tubing.


A run that would bring your hypthetical 5 gallons of working fluid from 45°F to 90°F would put 1800 BTU into the tank, melting 12.5 pounds of ice. Assuming you started with more than 12.5 pounds, the fluid in the tank/cooler would still be at 0°F (or 32°F if you didn't put any salt in the tank). The temperature of your working fluid that you pump through the coils and through the intercooler would always depend on the heat transfer in the coil in the cooler, but if you had enough tubing in the cooler tank, you could maintain the temperature of the fluid entering the intercooler at close to the tank temperature. If you wanted to keep the intercooler core cool, you could PWM based on a coolant loop temp sensor at the outlet from the intercooler core, running low flow untill the temp starts rising, and going to full flow as soon as the temp increases.

 

Is there a build thread or more pics anywhere? I did some searching but couldn't find anything. Thanks

 

Bring this thread back, I have a slightly different idea. With the advent of EV cars, a lot of engineering has been done to make things work that the engine would usually drive, like ac. I keep seeing electric AC compressors popping up in a bunch of builds that are tight on space. Everything from vintage Porches and Beetles, to 30s trucks. Using an electric compressor would certainly reduce complexity as you would have an entirely separate system. The only thing is that you may need to upgrade to a higher output alternator. So you wouldn't need valves to switch from cabin to intercooler water tank. What do you guys think?

 

I thought that EV AC compressors work off high DC voltage. There are electric compressors out there that work on lower voltage.

I think having two separate systems gives you many redundant parts. No matter whether the compressor is electric or belt, it's easier to have electric controlled valves provide cabin A/C as well as IC cooling.

 

They do make them to work with regular 12v cars with limited space. is an example.

Fair enough on the redundant parts. I do like the idea of a separate system so the cabin would still stay cool. That is certainly a concern out here in AZ. Have you been able to find electrical controlled ac valves? I have looked a bit and asked at an AC shop and could not find anything.