Shouldn't make a difference where the hull is made. IGB's all made at Westland and the engines are all made at the same factory in Quebec.
The new MGB is the same internally as the old MGB with the same oil cooler and blower. Just has the two reservoirs added on top of the most critical element of the 139 MGB, the high speed inputs. Assures 30 minute run dry for O&G, even though the test MGB was run for a total of 1 hour without oil (you can pull it apart on the maintenance simulator in Italy if you are interested and check out the gears
).
If you're having MGB temp issues, pull the oil cooler and clean out the fins. If your mechanics are over greasing the swashplate (which a lot of Bell mechanics do!!!) then the excess grease gets flung off, clogging the fins on the cooler. You can see a 20C drop if it is very dirty.
As for a nominal MGB temp, anywhere in the green range
Are you running air con. Are you running an AGB. are you running AC Generators. Are you running Super Silent gears. They all impart a load on the MGB, which will affect temp. Ambient temp also will affect MGB temp. I can tell you that the MGB runs nice and cool when it is -40C.
But the biggest factor I've found is a dirty/contaminated oil cooler.
