Disco 2 TD5 Loss of performance - intercooler heatsoak

With the setup of the cooling systems for the discovery 2, there's the AC condenser mounted out front with the intercooler sandwiched between that and the radiator. I am convinced that this arrangement results in the intercooler progressively soaking up heat from the AC condenser, especially with very high prevailing ambient temperatures. Thing is, I have noticed that performance steadily drops off with the AC running on mine with average ambient temperatures of 36 degrees Celsius or higher. I believe this is on account of the fact that there is a marked reduction in the amount of heat lost by the charge air as it travels across the hot surface of the intercooler. This results in hot air with less oxygen content getting into the air intake with a resultant drop off in power. The other day, had the engine running with AC on after a run, pulled off the air intake hose, had my mate rev the engine up a bit, and the charge air pouring out of the hose over my palm was scalding hot. Question is, are there any other options for charge air cooling for the Td5, relocating the intercooler or otherwise. I know this may not be much of a problem for those living in cooler countries, or for models without AC, but any thoughts on how to hopefully re-engineer the setup would be welcome.

From my knowledge of the systems in the D2, the first question must be how clean is the inside of your intercooler?
Next, don't quote me but I believe that an uprated intercooler might be available for the Td5 D2, if you search for one.
There is normally a drop-off of performance when the A/C is engaged, just because of the additional load on the engine.

First of all is the electric cooling fan working?

sierrafery said:

First of all is the electric cooling fan working?

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Yes Sierrafery, the electric fan works. I find that the condenser on the disco 2s dual AC system puts out a lot of heat load out front. One of the options I have been considering involve replacing the stock electric fan in the front with a larger more powerful one if possible.

You can try a dual fan setup...as about the inlet air temp, you should see the reading with tester and if it doesnt exceed decent limits(max 30*C more than outside temp) the fuelling will not be affected cos as long as you dont have EGR the IAT is below what the Td5 gets from one with non cooled EGR regardless or the condenser's radiant heat.... better rule out other common power reducing issues first

I ran a td5 for 4 years it was dead posh and had rear a/c which may be irrelevant but there you go!

What I was going to say in them 4 years i never once heard the viscous fan come in, then I fitted a large performance intercooler first big hill I came to as I crested the top in came the fan at full chat, the point being a bigger intercooler may not be of any help as it obviously restricted the air flow to the main radiator.
I also stuck a thermocouple in both ends of the new super duper intercooler and was most ****ed off to find it didnt cool any better than the std intercooler!

Allisport do a full size IC for the D2 with AC, wortg fitting imo, only takes a few hours.

lynall said:

I also stuck a thermocouple in both ends of the new super duper intercooler and was most ****ed off to find it didnt cool any better than the std intercooler!

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I fitted a performance intercooler to mine and compared IAT readings saved with nanocom and the readings were lower with the bigger intercooler especially under load

What about rigging up a water/methanol spray - they are used to cool the intercoolers on race cars and appear to be very effective and cheap to install.

sierrafery said:

I fitted a performance intercooler to mine and compared IAT readings saved with nanocom and the readings were lower with the bigger intercooler especially under load

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How much lower? I measured temps before and after the cooler and there wasnt any real difference, 70 degc springs to mind.

My measurements were made at around 20+C ambient temp and with the bigger intercooler the IAT never exceeded 37 while with the original i've seen even 50... that's from memory cos i remember i was pleased with the result didnt save the logs for posterity to be able to prove this....if you've got 70 IAT it means there was at least 40*C outside or your gauge is innacurate cos it's not normal to get more than 30*C difference between AAT and IAT whatsoever on a well working engine unless you have cooling issues and the radiator is too hot or the boost was low