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Hello,

I do believe that this may belong in modifications sub-forum since I am primarily pondering on a premise for a modification. But my questions are more technical than how-to-mod:
a. For a standard street car with a turbo diesel motor, how much benefit does an inter cooler bring in?
b. during particularly spirited runs ( highway?) and jam-packed-b-2-b traffic, what is the delta impact on intake temperatures?
c. if the intake temperature was to go down by some delta thru some modifications, how would it help with the overall health of the engine?
d. What are the possible demerits a inter cooler sprayer running a 50-50 mix of rubbing alcohol and low ppm water?
e. how much delta temperature impact could a spray like above bring about?
f. Though this is purely from a engine health perspective, Do tell me if I'm in for some torque gains ..:D
g. it won't have any positive impact on the mileage, would it now? :p

I have a 50:50 highway-b2b mix run of 100km daily. i push hard on the highway and things barely crawl in the b2b...hence this idea.Ambient temperatures can hit 45+ easily.

Hoping this thread to become Inter cooler 101.

great thread. even i was thinking of starting it for petrol motors but as you said lets make it inter cooler 101.

My focus is basically on performance but i would like to know answers to above questions as well.

P.S. - what is the difference between a intercooler and a cold air intake?

CAI is basically a modification of the intake/filter so that it sucks in comparatively cooler air, from 'outside' the engine bay. It generally involves plumbing and putting a conical(or other design) filter right next to the front grill. CAI is mostly a modification.

Inter cooler is primarily a post-boost component of a turbocharged intake. it helps cool the compressed air heated up by the turbo. Inter coolers are standard on most turbo/super-charged vehicles.

You may find CAIs installed on turbocharged intakes too, to achieve better inflow than OE filter/intake manifolds.

Along with it, I would love to know if there is any technical reason for Ford NOT ploking an inter-cooler in their 1.4TDCi mill. If nothing, then can we do it? Or any space constraints?. And, If we manage to plonk it in, what will the average bhp/torque gains.

Let me add pne more question - how does the intercooler cool the air given that the engine bay area is already hot?

Subjective to the exact location of the inter cooler, the fresh air fed into the engine bay helps in the cooling. In my car, the inter cooler is placed before the radiator, behind the bumper grille.

the location of the inter cooler has been of much debate. some common arrangements are TMIC, FMIC, SMIC.

TMIC = top mounted inter cooler. e.g: indica.
FMIC = Front mounted inter cooler. e.g: linea.
SMIC = side mounted inter cooler(?). e.eg: scorpio(?)

Vina, at full full throttle and boost, the temperature of air coming from the turbo can be well over 130-150 degree celcius. Engine bay does not reach temperatures so high, also in most cars, the inter-cooler is positioned in such a place where there is max air flow, just the the radiator.

After all its a heat exchanger.

^^ What are the temperatures found in the boost, and the engine compartment areas? Which area is the hottest?

Spike

from shallow research:

boost temperatures can be upto 40-70C above ambient?
engine compartment areas : well, isnt this question way too subjective?

hottest : turbo, exhaust plumbing should be hottest!

Any answers to the queries i put above, spike? :)

I have tried to answer your queries in bold above. Any other queries?

Spike:D

i was pointing to the opening post :)

as far as boost temp is concerned, i feel it shouldnt be above this for normal consumer cars? referring to the smaller engine cars with <2.0 capacity.

thanks

so how much heat can the air lose and how much density does it again via the intercooler in a typical diesel car (or truck)?

also is it so that a car moving at a moderate speed will have better intercooler performance than a car that is stationary (don't ask me why would turbo be needed for a stationary car)

allow me to alter your question a little:
case a: engine at 2k rpm in 2nd gear.
case b: engine at 2k rpm in 3rd gear.

quite obviously, there will be more air passing through the inter cooler in 3rd gear ( car moving at higher speed, hence more air cutting into the engine bay), hence the heat transfer will be better. but then, this gain won't be linear. As the speed climbs, the air inflow into the bay can actually reduce ( too little time, too much turbulence) and hence reduce the cooling efficiency of the inter cooler.

turbo function is more a function of engine rpm than speed.

Dear All,
Before you go any further try to get hold of the torque/bhp curves for the Nissan Micra and the Logan/Verito. Both share the same turbo charged engine but one does not have the inter-cooler and the other has it.

Learning about the performance and characteristics of these two engines should give you most of the information you want.

Spike, well theoretically, the Turbo outlet temperature =

Tout = Tin + Tin x [-1+(Pout/Pin)0.263]
efficiency

Source: Turbocharger Compressor Calculations

The best area to place a intercooler would be just behind the grille. Ram air at speeds is very effective.

If the bay is cramped, then top mounted would do the job, but then it would warrant a hood scoop. Also, the convective heat transfer from the engine would be a negative.

As for which area is hottest, I guess your question is answered in the above posts.
Why do you ask questions for which you already know the answers?. :p

Vina,

Turbocharger Compressor Calculations
Intercooler Theory

These two links provide very expansive knowledge about the subject.

Now, keeping my mount shut about why would turbo be needed for a stationary car or even if the exhaust pressure at idle is enough to spin the turbo :D

If the performance of the intercooler depends on the ram air, then YES the performance will be less when the car is stationary. As I mentioned before an intercooler is a hear exchanger, and it need to transfer the heat to the surroundings.

The best example for this would be your car's AC. Usually AC is effective only when the car is in motion. AC performance in a stationary car is much less than in motion.

Are you sure the Indica has a TMIC?. Which model?