[TrollToll]

I noticed today (by ordering the wrong part) that my 535i uses a different expansion tank cap than the 135i and 335i. The 535i uses a cap marked with 200 (2.0 bar, 29.00 psi) while the 1 and 3 series use a 140 (1.4 bar, 20.03 psi). That said, since they run different pressure, does that mean that they likely run different thermostats and or DME controlled temps? Would it be advantageous or even feasible to convert one system to the other for lower running temps?