SBC pulley ratios

[41woodie]

So in the process of adding A/C to the Woodie I hit a question.  Up until now I've been running two belts, one to the Alt the other to the P/S pump.  The water pump pulley is 6 1/4" diameter, the crank pulley is 6 3/4" and the P/S pulley is 5 3/4".

I'm running a mechanical fan and to hopefully stay ahead of any heating problems I want to change the crank pulley to a 7 1/4" model to increase the fan and water pump speed.  

So far I've installed the 7 5/16" two groove pulley and added a 6 3/4" add-on third crank pulley to run the P/S pump.  By using the smaller diameter add-on pulley I won't be changing the pump pulley ratio. (it seems to perform properly so I didn't want to mess with it).

Question is, by increasing the diameter of the crank pulley to "speed things up" will the A/C Compressor or Alternator be adversely effected by the higher RPM?  I don't remember ever seeing an up sized alternator or A/C pulley.  

If my math is even close my current set up of 6 3/4" crank pulley and 6 1/4" water pump pulley would mean that the water pump pulley would be at 5940 RPM if the crank pulley is at 5500.  With the 7 5/16" crank pulley the water pump pulley would be at 6325 RPM at the same engine speed.  Is this increase anything to be concerned with?  Thnx Mike

[enjenjo]

I don't think it will cause any problems with the alternator or AC compressor, unless you spend a lot of time north of 5000 rpm

[41woodie]

I don't think it will cause any problems with the alternator or AC compressor, unless you spend a lot of time north of 5000 rpm

Spend very little time at that RPM but occasionally I feel the need to revisit my misspent childhood and wind things up a bit.  Unfortunately the woodie doesn't go faster it just gets louder.