[Dessertrunner]

I have my head around how the pressure and suction works, this is the rule.

The flow through any part of the circut "AFTER" the largest pressure restriction must be greater in vacum then the flow through that restriction.

You need to take on board what Ironhydroxide said about the straw test and remember that the suction has to be a lot larger then the pressure side. In my example before with the stand alone pump I had 33mm from the outlet to the inlet of the pump. Under this set up the 33mm was not a restriction to the pump so there was no pressure reading BUT it was a restriction to the suction as it was to small and caused the pump to cavitate. When I changed the pipe to 45mm but left the oulet cap on the pump at 33mm that point became the point of restriction or pressure. The suction side at 45mm exceeded or staisfied the rule as it was larger in flow under suction then that the flow on the pressure side.

If we apply this rule to our standard cooling systems we find that the main top pipe etc are 33mm and the therm cover is 29mm we have a major problem. It is worth noting that any problem on the vacum side can be found with a vacum guage into the suction of pump.

SilverSpear in answer to your question about left and right bank temps there is still a 2-5 degree difference between them. It is not related to the position happy to explain if you want and how to fix.
Tony