what is going on?

[adzs12]

My gauge never goes past a 1/4 of the way up the gauge as my twin kenlo hurricanes dont allow it too , so i found it odd when it kept creeping up to half way. Il change the thermostat anyway as the cooling system could do with a flush out and fresh antifreeze before the frosts really set in. As for the slight hesitation on boost and it feeling retarded il have to see what i find.