Which Intercooling System Is Best?

"PS9" (PS9)
01/21/2014 at 16:29 • Filed to: None

Raised intake temperatures are a consequence of forced induction. To deal with this problem, engineers use intercooling to lower air intake temperatures back to normal. One is Air-to-Air, the other is Air-to-Water. Which one is best?

It appears the F80 is going with Air-to-water this time. I wonder if that was due to reducing underhood intake plumbing (which as you can see here is already considerable) or for some other reason. I now have a flimsy excuse to post the Veyron's Air-to-water engine porn.

Think we'll see more of this in the future? What do you think the best IC system is? If you were doing a turbo build, which would you pick?

DISCUSSION (23)

Textured Soy Protein > PS9
01/21/2014 at 16:33

Air/air intercoolers are more simple but need to be big to give good efficiency.

Air/water intercoolers are more complex but take up less space.

I can see more car companies doing more air/water setups, because the air/air intercoolers needed for the crazier turbo motors will just be too big to package into cars and still meet crash standards.

offroadkarter > PS9
01/21/2014 at 16:36

Its technically "Water to Air", but I won't be that guy

I think W2A is a more efficient setup overall. As long as you can keep the coolant cool, you'll keep the air cool.

Casper > PS9
01/21/2014 at 16:38

Air to water is always the best for straight conversion... but it's added complexity and cost usually make it less appealing than an air cooled solution. It also adds some weight as water is fairly heavy. Toyota did a good job on their Celica All Tracs with air to water IC. You also see a lot of drag cars doing it because it doesn't require a ton of air access for their short runs (and they can ice them).

Personally I like water cooling for some applications, especially if it's going to be pushed hard for long duration but not necessarily moving fast (off road racing and the like). My cars are air to air because of the simplicity and cost effectiveness to replace/change up.

Mattbob > offroadkarter
01/21/2014 at 16:39

why is it "water to air" as opposed to "air to water"? genuinely curious.

offroadkarter > Mattbob
01/21/2014 at 16:40

Thats just how I've always seen it refereed to as. I mean, this could be a tomato tomato incident.

stuff!

deekster_caddy > PS9
01/21/2014 at 16:41

It depends if you have space for an air to air - you need a side mounted super/turbocharger to be able to route the ducting. If you have an intake manifold mounted supercharger, air to air isn't an option.

There are added complexities to air to water, however it's usually much more compact.

Would need to see some 'lab measurements' or other testing to see which removes more heat.

BJ > Textured Soy Protein
01/21/2014 at 16:43

Would an air/water system weigh more? And what about center of gravity? On the Veyron setup, it's clearly at the very top of the engine, where it has the biggest impact.

Mattbob > offroadkarter
01/21/2014 at 16:57

yeah, looks like it could go either way, the first search result says air to water. I would think it would be air to water though, as the heat is transferred from the intake air to the cooling liquid.

offroadkarter > Mattbob
01/21/2014 at 16:58

it goes both ways

like a bisexual

desertdog5051 > PS9
01/21/2014 at 17:13

Big trucks abandoned liquid to air a long time ago because it did not produce the same power as air to air.

Textured Soy Protein > Textured Soy Protein
01/21/2014 at 17:18

I'm no engineer but I don't think the air/water setup would have much of a weight penalty over a big front mounted air/air intercooler and its associated ducting.

It really comes down to packaging. A front-mounted air/air intercooler sits in front of the a/c condenser which sits in front of the radiator. So a car manufacturer needs to spec strong enough fans that will pull air through all 3 of those things, figure out how to route the intake ducting down into the front bumper, all while still making sure the car meets front crash standards.

So if you have a heavily turbocharged motor and would rather stick to packaging everything more tightly and not deal with all that intake plumbing through bumper supports and such, then a water/air intercooler makes sense.

SantaRita > PS9
01/21/2014 at 17:22

Lots to consider. Air/liquid cooling is going to cool the air more most of the time, and can be a much smaller route to plumb. Can be made to go colder than ambient temps.

Air/Air is simpler, but you sacrifice short runs unless you go TMIC, at which point its time for hood scoops. Air to air you're limited to ambient temps on air cooling. This is why a FMIC is sometimes better...it's hanging out in the wind getting cooled off instead of soaking up hood temp.

You can also do a sprayed air to air IC (Misting system) to mix the ideas a bit.If that's not enough there is always water/meth injection.

Gizmo - The Only Good Gremlin, but don't feed me after Midnight > PS9
01/21/2014 at 17:46

This was one of my biggest issues as I raised the power of my tiny V8. I was experimenting with a new supercharger setup and ended up with 24lbs of boost. Problem was, that much compression generates a lot of heat and my ECU kept pulling timing once IAT2 reached 128*F. Several dyno pulls while tuning showed IAT2 at over 200*F. My solution was add a reserve tank (my car initially had none) and Water to FREON.

The system I have is called the ActiveChiller Super Chiller. When activated the system reroutes the Intercooler coolant (ICC) from the air intercooler to a separate heat exchanger that has water on one side and Freon from the air conditioner on the other. The results were amazing. Cruising in normal mode (freon supporting bot A/C and chiller) ICC temps stayed below 55*. I use Competition Mode (freon to chiller only) for Standing Mile racing and from the time I finish a run and idle back to the starting line, my ICC is back down to 43* and the supercharger inlet is sweating cause its so cold. Max IAT2 during the run was 124*F.

Kinja'd!!!

The tank helps tremendously because that's where the superchilled water waits to go into the supercharger. Since my ECU cuts off the A/C at WOT I have to rely on that tank for cooling during my runs and we've determined its plenty for 1/4 mile or standing mile. It also helps for track days since the system is chilling the water whenever I'm not at WOT.

Kinja'd!!!

As a safety precaution, the system will always default back to the air to water intercooler.

1337HPMustang > Gizmo - The Only Good Gremlin, but don't feed me after Midnight
01/21/2014 at 18:11

commenting for future reference when I've got enough money for a supercharger

Gizmo - The Only Good Gremlin, but don't feed me after Midnight > 1337HPMustang
01/21/2014 at 18:24

These have been around for Mustangs for over 10 years. Their called Killer Chillers by Kincaid Performance out of Albuquerque, NM. I went to them first, but they weren't interested in building a custom system unless I brought them the car (1065mi).

OBTW, you might recognize the mod I did to my supercharger: Snake Bite Stage 5.

BiTurbo228 - Dr Frankenstein of Spitfires > Gizmo - The Only Good Gremlin, but don't feed me after Midnight
01/21/2014 at 18:25

Kickass system. I wonder what the power gains are vs a standard tank that isn't being chilled, considering it takes power to compress the A/C system.

Gizmo - The Only Good Gremlin, but don't feed me after Midnight > BiTurbo228 - Dr Frankenstein of Spitfires
01/21/2014 at 18:54

NONE! The issue is not to gain power or torque, but to keep what I have (502RWHP/486TQ - that's 40% over stock). An additional tank is going to help the cooling if its after the intercooler and well insulated. Most guys with overdriven superchargers just opt for a larger intercooler = more water and more cooling surface; while the drag racers go for larger intercoolers and open tanks to drop ice into.

So many people say that about powering the A/C. The A/C does not affect racing performance. If I'm not at WOT, there's ample power available that I'm not using. When I go WOT, the A/C automatically cuts off. No loss.