Chevrolet: Intake Manifold Heat Level, chevy impala, clutch fan

Question
Roger, You helped me previously regarding my 66 Chevy Impala 283.  I did get the 2 bbl Rochester carb and it runs great.  However, I noticed that the intake manifold (painted Chevy orange) is discoloring (almost getting near black) in the areas right across from the carb.  The same thing happened with the old carb.  I was just wondering if this is a problem I need to address or put it down to the paint just can't take the heat in those areas.  At cruising speed I stay at 180 deg.  Idle it goes up to and stays at 200 degrees.  Any ideas?  Jer  

Answer
HI Jerry;
        First it is great that the 2bbl is working well for you and as far as the discollering it is the paint or some fuel could also be making the paint wear off, I would not worry about it, as far as the temp , do you have a thermastadt, change it to a 160. and how about the fan is it close to the rad. or far away, do you have a shroud ? and a clutch fan is good but a flex fan is even better.     and if the fan is to far from the rad. it will not cool it down as much.and w/o a shrowd you can also loose cooling. but as long as you are not overheating you are fine.
hope I helped you.
Roger, take care