there was a thread about this on the lotus 7 board a while back, they were saying you dont need one at all until you get above about 230BHP. I have no idea why they are standard on GTE16v's. But i know the calibras never had them fitted with the 2.0 16v its all a bit of mystery.
My mate done a 16v conversion on his nova and he put the oil cooler on and when he turned the wheels on full lock they rubbed on the pipes and burst which was not good so he just done away with it and had no probs without it, you could reroute the pipes though if you really want one.
When I got my Astra the oil cooler had been removed an some one had welded over the ends of the pipes where they went into the sandwich plate to stop the oil coming out! This just ment that when the engine got to running temprature none of the oil went through the filter. Not good!
It would have taken a fraction of the time and effort to remove the sandwich plate......
On a fairly standard normally aspirated 16v engine its perfectly OK to remove the oil cooler. In order to do this remove the sandwich plate located on the oil pump. The trouble is now you have no way of affixing the oil filter.
In order to overcome the problem you will need to obtain the screw thread from a Vauxhall engine that normally runs without a cooler. Screw this into the oil pump (where the sanwich plate used to be) and hey presto you now have the thread to screw your filter back on to the oil pump.
My opinion: If the engine has an oil cooler, make sure it keeps it.
Why would Vauxhall fit a cooler when it’s not necessary??
Somehow Vauxhall thought that the oil temperature becomes to high, and it needed to be cooled.
I don’t have one, so can the people who say it isn’t necessary tell if there oil cooler never gets warm? Do they have an oil temperature meter so they can tell how hot the oil gets?
Problem is you won’t notice that the oil gets to hot. The engine keeps running, “no problem” but... Hot (overheated) oil will “wear out” faster, so the quality of the oil becomes less.
Hot oil is also thinner and the hot oil film will be broken easier.
But you probably notice that when your bearings are all ready damaged....
Also when your fitting a 2.0 into a nova, your not the kind of person that has a modest way of driving...Are you?
English isn’t my native language, I noticed I don’t know the right words, but I hope I get my point across.