The inspiration for this upgrade came from Bob (staatsof) on the BiturboZentrum forum, who recently fitted this cooler on his track Ghibli Open Cup and kindly shared pictures of the fitting to the forum members. I was already looking to fit an oil cooler after my experience on the Assen TT track last year where my oil overheated when the car was stationary after completing a couple of hard laps. However, I was looking at installing a conventional oil/air cooler and hadn't considered fitting a oil/water cooler, but after reading Bob's comments it made perfect sense for my application.
The Mocal Laminova oil/water cooler is a heat exchanger that flows oil through the centre of a core and water around the core. The oil is pumped via the oil pump on the engine block and water comes from the engine cooling water system. What makes the system so good for me is that the cooling water quickly warms up to about 60 degrees centigrade in the engine block before it then starts to circulate through the engine radiator. It is at this point that it starts to circulate through the oil cooler and initially it actually warms up the engine oil, meaning that it actually helps warm up the engine quicker. The quicker the engine warms up, the less likely you are to over-stress it. Therefore, when the oil is cooler than the water, it actually helps keep the water temperature down and there's less need for the radiator fans to kick in.
I like the idea of the entire engine block running at an even temperature, rather than having hot spots where different fluid circuits are flowing.
The installation of the cooler went really well. Rather than try and explain this, I've posted a load of pictures with lengthy descriptions that should make it all clear. The installation looks pretty professional, although as Jorrit pointed out, probably four too many tie-wraps used to get away with it looking like a Maserati fitted system.
I've not had the opportunity to give the car a good drive yet, but on the way home I did notice that the engine temperature was running a bit lower than normal, with the water temperature not getting above 80 degrees on the gauge and only once did I hear the fan come on when I was stationary in town. So it appears that in normal use, the oil is actually cooling the water! This is a good thing, since it likely means that the oil before wasn't really getting up to its optimum temperature with normal driving.
One thing I learnt is that my Ghibli (the first non-ABS variant) has a slightly unique sump. The reason it didn't have a cooler is because the sump on my car is a little taller than previous Bi-turbos to provide for a bit more air cooling. But it turned out that the reduced ground clearance led to leaking sumps from the increased abrasion with the road, which is why Maserati went back to the shallow sump and fitted an oil cooler to give the required cooling. Since my car has the taller sump plus an oil cooler, I shouldn't get any problems with cooling now. However, I will be fitting the shallower sump as soon as I get a leak on the current one, since I wish to drop the height of my car a little, but the clearance is a little tight as it is.
I had a couple of other things changed while the car was with Jorrit. The front bushings had worn out and I was getting some play when I pressed the brakes, which wasn't very confidence inspiring. So I had the bushings upgraded to the later Ghibli GT design. The consumable rubbers for these bushings are much cheaper than my original ones so I should recover the cost in the long run. The car's feeling much better to drive now though, much stiffer and less creaky at the front.
Also, still trying to figure out the cause of the stuttering problem, I asked Jorrit to fit a known good distributor to my car to see if this is the cause. He did so and I initially thought that the problem was solved on my drive home until I managed to induce a stutter again by accelerating hard in third gear. It only happened once though so I need to do a few more miles to be conclusive.
Next on the agenda is repairing or replacing the radiator as it has started to leak and it seems to be getting worse. Jorrit knows some guys who can refurbish the existing radiator, essentially by fitting a new core, but this could be an opportunity to install a new aluminium one?
