I have an IO-360 from Lycon with 10:1 compression pistons.  I have the same worry about my servo.  It's been rebuilt twice and have told them to increase the top end flow.  I have the RSA-5AD1 servo.  Mine puts out about 17 to 18 GPH, but that is only measured from the spider pressure, not a true fuel flow.  My CHT's run 430 to 440 in the summer.  I just built a plenum to try and cool it down in the climb. My CHT's run 390 to 400 in cruise.  

Luke Alcorn
NATCA ZJX Safety Rep