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E39 Engine Oil Cooler Final Setup

With all the engine tuning modifications the inevitable core/oil heat would build up in the engine, simply because there is more horse power. You can read about what I have altered and change within the engine with other pictures.

When the core heat in the engine rises, the heat in the engine compartment rises to, and that leads to amongst other things a warmer intake manifold. Consequently, that translates to warmer air when it reaches the head intake itself. Therefor it is preferable to pump cold air into the engine, sins it is denser and gives you the possibility to ad more fuel that translates then to more horsepower.

The modifications where relatively simple and straightforward and not that complicated (until it explored in my face). I bought the 13 row oil cooler from a seller on eBay. The hoses had to be shortened a bit to be fitted snugly and two holes made in the bracket that hold the water radiator for the oil hoses. The oil cap was bought separately from another seller.

You scold be on your toes when choosing the oil cap, sins there are some caps for sale that are missing a vital part that goes into the hole at the bottom of the oil filter housing/canister. If this hole at the bottom is not closed the engine will not reach a full oil pressure. This hole at the bottom has two purposes, one is, when you take of the original cap the oil is drained through that hole to prevent oil spill and the other is in some cases if you have a pin with two rubber seals the middle pin is hollow and has the capability to bypass oil through it and come out at the top of the inside of the cap to prevent an over pressure. As far as I know then none of  these aftermarket caps have the mesh that goes inside the filter itself and finally some of the caps, use the inside part of the original cap in conjunction with the aftermarket one.

My issues with the fresh intake-air heat in the intake manifold and the engine, was that it reached 62° - 70°c /144° - 158°f air temp. measured inside the manifold, at standstill and idling, with outside temperature at 20°c/68°f. To tackle this heat buildup I had two simple choices, Ether more cold air from the outside or an external oil cooler. I opted for both solutions and the results where that the core heat (mostly the heat of the oil) of the engine dropped  from 103°c to 93°c/217°f to199°f, or 9% lower and air temp inside the manifold from 62°c. to 43°c./144°f to 109°f., or 7%. Now, that might not seem a lot, but then this is measured at standstill and idling. When driving the numbers get much better.

The original air intake plastic tunnel got the air all the way from the left middle of the front bracket and actually, partly inside of the engine compartment where there is to much warm air.  As you can see I cut it over to allow cold air to come more freely in, in conjunction with an air filter box that has an additional intake from the inner side of the wing that leads to the wheel well. 

I am pleased with these results for now, although I'm dabbling with the idea of a larger oil cooler. Now I can continue with the fine tuning of the partial bin. files, sins all the parameters have changed due to overall a cooler engine and colder air intake.

After the installation I opted for painting the cooler in mat black heat resistant paint.

From the album:

My 523i Conversions and Maintenance

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