Uprated Intercooler installation


A few weeks after completion of the 2.8TGV engine installation, I reconnected the boost gauge on the dashboard. The gauge is T'ed into the line from the turbo to the fuel injection pump. I would prefer to tap the gauge into the plenum chamber, but the tapping in the rear is M8x1.0 and I have been unable to locate a spare bolt to adapt to a fitting.

Once the boost gauge was functional I noted that the maximum boost level is around 19psi (compared to around 15psi for a 300Tdi). With the expansion in engine size from 2.5L to 2.8L, this corresponds to an additional air demand of around 41% . While this means that service items like air filters are much more important to performance, it also means that the inlet air temperature of the engine is higher as the intercooler will be unable to produce the same temperature drop for the higher air volumes.

There are many aftermarket operations offering upgrade intercoolers, some of which are huge compared to the original part, and most making large claims for additional power available. My aim was not to increase power per se, but to reduce the inlet air temperature close to where it would be with a standard 300Tdi setup. Allisport offers a standard sized intercooler rated to have 40% greater cooling capacity. The Ibex front end is would not easily accomodate a larger than standard intercooler, so this seemed a great option. Additionally, I have looked at Allisport products in the past and always been impressed with their build quality.

intercooler1.jpg Allisport replacement compared to Land Rover part.

The quality of the welding and construction of the Allisport unit seems to be of very high quality. The main tubes which carry the inlet air are thicker than on the OEM part, and internally divided. The spacing of the cooling fins are larger which bodes well for getting the mud out on some future occasion :-) The end tanks are smaller, allowing the cooling tubes to be longer.

Fitting the unit is straightforward, though awkward since I wanted to avoid opening the cooling system which makes access more difficult.

intercooler2.jpg Intercooler installed.

On the road, the effect is slight but noticeable. On long hills, the truck holds speed much better, especially with the overdrive engaged. Full throttle acceleration seems better too, though that was unexpected, since the fuelling has not been adjusted, and it did not smoke beforehand so there was no excess fuel to be used up. The reduced EGT must be better for the engine in the long term, and should help get to that 200k mile lifetime expected from the 2.8TGV.

QUESTION : Why are intercoolers always bright, never painted black? Black bodies radiate (and absorb) heat better (which is why car water radiators are painted black?). Is it just easier to sell shiny things? Does a 20um paint coating increase the heat capacity or reduce the heat loss available? Are they just too hard to paint without blocking the small holes? Is it to reduce heat absorbtion at lower speeds? I don't know, but someone must !!!!