engine running hot after getting work done

[Grdenko]

yo,

i recently had some work done, as ive mentioned, new cylinder head, turbo works now...

anyway, now my engine runs at about 90-100c and even as high as 110c sometimes, instead of a cool 80-90c like before. i figure that some of this can be attributed to the turbo, but not all of it.

it seems like my car always runs hotter after the shop replaces the coolant, so im thinking that they use too much anti-freeze, which ive been told does not cool as well as water.

my questions:
is it true that too much antifreeze reduces cooling capacity?
what is the ideal mix for summer driving?
whats the best way to drain just some of the coolant?
what is the ideal engine temp?

thanks