Cold air intake (literally)

[mischf]

Has anyone experimented with using aircon piping to cool the intake? Like welding radiator fins onto some piping, and putting it inside the intake. My pipes get pretty cold, and was thinking... wouldn't they be more useful if they ran down the inside of the intake tube. With fins on them they would radiate cold air straight into the engine

[immortality]

i believe it has been done but mostly on intercooled supercharger/turbo etc. another variation of this is the water to air intercooler, this is where a thin radiator is sandwiched between the supercharger and itake manifold and they pass a cooled liquid through the radiator so that it cools the intake charge as it passes over the little radiator. check the PWR website, i believe they are doing something like this for there supercharger setup

[Apoc]

Ive thought about that too but i tend to think the power lost to having the air conditioner on is going to offset any benefits that might be gained from cooling the air. Dunno for sure though...

Apoc.

[vq~gangsta]

I do know for sure, it's a well and truly a crap idea.

If you're sucking the air from the atmosphere, lets say it's 21 degrees (room temperature) - if it then runs through the fins, which are also at room temp, since there's no temperature difference, no cooling will occur.

When air comes out of a turbo or super charger, it's often over 100 degrees, thus when it runs through the 21 degree fins it gets cooled. Likewise, radiator liquid from the cooling system is also just over 100 degrees, so running it through 21 degree fins will also cool it.

You can not cool room temperature air by running it through fins that are also at room temperature. You need the fins to be colder that whatever's running through them for to cool at all.

[knowledge_is_power]

I think mischf is referring to the return pipe from the evaporator to the compressor of the aircon system. You will notice that the pipe gets colder then ambient temperature as condensation forms on the pipe and ice in some cars.

Some Pro dyno cars chasing large hp (like 1000+hp) use an aircon system on both air intake and intercoolers. Largely due to the issue of heat soak associated with dyno’s readings with almost nil airflow.

I believe that if you could make the pipe with fins efficient enough it may affect the intake temp. In saying this I also believe that the amount of hp generated by the cooler air would be less then the hp used to run the compressor. You could gain some benefit by running the aircon, then switch it off for a very short period for increased performance, possible for a TLGP, but that’s it. The return pipe would lose its cooling ability fairly quickly. Also you may reduce the cooling ability of the aircon to cool the cars interior. The hotter the gas is before compression the hotter it is after compression and the harder the condenser has to work to shed the heat before the gas enters the evaporator.

Jezz

[mouce]

Not to mention the fact that you'd end up with a disturbed air-flow due to the fins. Having stuff in the intake system that causes turbulance in the air-stream isn't going to do you any favours.

[xcop5l]

the only place you want turbulance is in the cylinders as it produces a better burn

[vq~gangsta]

what do you think about those induction fans you see on ebay, the 'electric turbos'

would they be a load of shit or what. I figure, its so basic, that if it worked that well they'd be on stock cars too.

[mouce]

They suck. I think that sums it up nicely.

It's like those resistors that you plug in across the air temp sensor. About the only effect it has is to make your wallet lighter.

[s0sage]

well its all about weight reduction mouce

intake fan to spin your air .. stage 1
fuel saver .. stage 2
turbo pop off noise on yuor exhaust system .. stage 3

[mattman]

They suck. I think that sums it up nicely.

No.. I think the problem is that they don't suck

[Cheap6]

To return to the original topic for a bit:

Since the ECM switches off the A/C at WOT the A/C load won't matter in terms of reducing any power gain due to colder air inducted. Fuel economy may be influenced if the A/C runs at a greater duty cycle.

Because the A/C is switched off at WOT and the thermal mass of the A/C piping is low, some means of storing (negative = cold) heat energy would be required in order to appreciably lower the intake air temp. Water would be a good substance to use for this purpose.

The problem then becomes one of transfering the heat out of the intake air into the cold sink without causing a pressure drop/mass air flow reduction greater than the gain due to the lowered temp. While a heat exchanger, like a heater core in the intake path, may work in terms of cooling the intake air, it would result in a substantial pressure drop. The best way that I can think of to avoid this would be to spray (inject) the water into the intake manifold directly. A preliminary investigation into how such a system will work would start with a simple water injection system using an ice-water mix before attempting to provide a means of generating the cold water using the A/C piping.

[vnstu]

Ive thought about that too but i tend to think the power lost to having the air conditioner on is going to offset any benefits that might be gained from cooling the air. Dunno for sure though...

Apoc.

if it's a hot day, and you're running the air con anyway, and the outside air temp is 30+c...

might as well use the cold point for something. even if you dont get any power benefits it might run better while you're sitting in traffic at noon...