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-   -   Intercooler: benefits and spray cooling? (https://www.team-bhp.com/forum/technical-stuff/102012-intercooler-benefits-spray-cooling-2.html)

a. An intercooler will always benefit if boost is at least 5 psi or more. The reason that less than 5psi is not intercooled due to:
1. Boost controllers (manual type) have spring pressure limitation.
2. The pressure drop accross the intercooler will be quite a bit ( upto 2 psi is acceptable).
3. Charge air is not so heated up above ambient if the boost pressure is this low.

b. When no-or-little air movement is taking place, the delta temps across the intercooler will be almost nil. This is due to the fact that is intercooler is acting like a heat storage medium in b2b traffic...though this is more so in diesels than petrol vehicles as diesels are on-boost much more than petrols. During spirited runs there is enough air passing through the intercooler to get good delta temps accross it.

c. The cooler the intake temps, the better for power & less chance of detonation.

d. The quantity od rubbing alcohol-water mix for daily driving will be quite on amount (say 3 lits every day) for your run (100 kms), unless you get a GOOD spray system (atomizer type) & automatic control of spray timings depending on delta temps.

e. A good intercooler spray system can get temps down to ambient.

f. Yes cooler intakes will result in torque & power gains provided your engine management system has been programmed for the cooler intake temps. Otherwise it will be a waste of time & effort.

g. Mileage always depends on how you drive. The gain using the above methods will be minimal.

Hope this answers the questions to your satisfaction!:)

Is this the case even for oil cooled intercoolers?

regarding d: how do we measure the delta temp? engine intake air (from OBD) - ambient temperature sensor?
also, some resources seem to suggest that a spray should be timed prior to a load condition.apart from a manual trigger when about to push hard, what other conditions should be 'programmed' for trigger?


regarding f: I have an MJD. how to figure out if intake temperature is an active factor in the system?


yes, quite so, thanks!

not sure. but i do remember observing an intercooler on some tata car. is it indigo? correct me and post an indian example of tmic, thanks.


as for oil/liquid cooled inter coolers, i doubt they are efficient over long-haul. you are essentially trapping the heat in the cooling system. yes, these would perform quite well for drag race kind of situations.

Yes, for any intercooler which needs air movement to do it's job. Hence the radiators of all vehicles have fans, which normally come on when stopped or at slow spped in traffic...(a/c fan not included in this discussion).
One does get DIY circuits with k-type thermocouples. One has to simply solder them in place. We place one thermocouple at intake side of the intercooler & the other at the outlet side. Both have LCD screens directly in the cabin. So you can manually calculate the difference & switch on the spray system.

The other system features an 'Intelligent' chip which actually senses how you are driving (attached to many sensors in the car) & automatically sprays the intercooler. This however in not cheap, costing over 250 USD for one.

Yes, spraying prior to a full load stress will do you good, again depending on how good your spraying system is. This is especially good for street cars in b2b conditions as the intercooler acts like a heat storage medium in the absence of air movement.:)

Any engine mgmt. system that factors air temps will have a sensor (thermocouple or more sophisticated ones) as part of it's sensor array. So look for it on the air intake box right to the intake manifold. It will be there.

Note from the Team-BHP Support Team: Please use the "edit" button if posting within 30 minutes of the first post, instead of creating another back-to-back post.

TMIC needs air to cool the intake, and in most designs, it is taken from a hood scoop. Now, which Indian car has a hood scoop?. I'm thinking.... :D

Umm.. you are not trapping the heat in the cooling system. Its like Air-Oil-Air. The oil or coolant just acts as an intermediate, just like most IC engine's cooling system.

• The good thing about oil cooled ones are that the plumbing or length of pipe required is less and the intercooler need not be mounted on areas with air flow. This means that the turbo outlet boost is not lost much on the way.

• The bad thing is that, they add to the cost, as well as weight, as well as they further cramp the engine bay.

Scorpio has top mounted ( atleast the cooling fins are on top) and scoop is just above it before mHawk this was decorative scoop but with mHawk it became functional.

In Xylo there is no scoop but there is a channel in the hood which diverts the air from front to top. Indigo I heard has similar solution.

I think the only reason for top mounted is cramped engine bay

i THINK earlier scorpios had SMIC, mhawk has TMIC. tata cars with TMIC had a air route designed into the hood, drawing air from the front grill area.

air-oil-air will lose its advantage after a short run, won't it? and also, after brief stoppages. for short runs ( when the oil is cold), it is certainly better.

I seem to have a poor knowledge of other indian motors...so ill refrain from commenting on them further :P

Well earlier Scorpios ( 2.6 Turbo) never had any inter-cooler as far as I know.

The Indica V2/Indigo have a TMIC with an under bonnet scoop with rubber seals for the intercooler. The Vista/Manza models, IIRC, have a FMIC.

Timing of this thread is a little in sync with an idea I am exploring.

My Sumo has a FMIC, mounted between the radiator & RH headlamp. Rather than a water spray cooling, I am thinking of using a 5V DC fan (may be like one that is used in PC/desktop SMPS units, and design a flare that will direct the air from the fan, over the fins of the IC and then away. This steady direction of air can help in a little more cooling for the IC.

And if it works, it will be a very cost-effective way of cooling the air input to the engine. While the water spray approach can induce better cooling, that will happen only when the water is sprayed. The air-cooling approach will be a continuous one, and due to this reason may be better too.

Not really. They had front mounted intercoolers.

Condor, the weak flow of a pc fan will in NO way cool the intercooler the way you are expecting. A better way would be to direct air from the front of the Sumo into the intercooler without the air escaping from underneath or the sides of the intercooler....in other words a kind of tunnel made from plastic & sealed around the intercooler with foam, thermocol etc.:)

Condor, I doubt the CFM of these CPU fans are sufficient to cool the inter-cooler. At speeds it might even prove to be a hindrance to ram-air flow.

@1self & Dhanush, thanks for that. Will definitely keep that in mind when I work on this. The SMPS fan was an example, but can you think of a better fan I can use ? Something small enough, yet one which can generate good flow ? I can also explore the possibility of running it on 12V if required.

The method I am thinking of is for the rear part of the IC. The front part already receives air from the front, through the grille.

@1self: your point about sealing the escape routes is valid. But regarding directing the air, your method will work better on highways. For city traffic, a good stream of air on the rear surface of the IC may really help.