'66 A/C Pulley

[Peter F.]

I have a '66 L79 engine with no PS or A/C. I am contimplating putting an aftermarket A/C unit in the car but am puzzled as to what pulley arrangement to have. The A/C manufacturer says I need a triple groove crank pulley with a double water pump pulley. The '66 shop manual shows just the two double groove pulleys with a longer belt connecting the crank with the water pump and A/C unit. Can anyone help? Thanks

[Craig O.]

Re: '66 A/C Pulley

I have a '66 L79 engine with no PS or A/C. I am contemplating putting an aftermarket A/C unit in the car but am puzzled as to what pulley arrangement to have. The A/C manufacturer says I need a triple groove crank pulley with a double water pump pulley. The '66 shop manual shows just the two double groove pulleys with a longer belt connecting the crank with the water pump and A/C unit. Can anyone help? Thanks

I think the triple grove crank pulley is correct but it is in two separate pieces making up the 3 groves .

[Joe L.]

Re: '66 A/C Pulley

I have a '66 L79 engine with no PS or A/C. I am contimplating putting an aftermarket A/C unit in the car but am puzzled as to what pulley arrangement to have. The A/C manufacturer says I need a triple groove crank pulley with a double water pump pulley. The '66 shop manual shows just the two double groove pulleys with a longer belt connecting the crank with the water pump and A/C unit. Can anyone help? Thanks

Peter-----

No 1967 Corvette small block ever originally used a 3 groove waterpump pulley and, consequently, no such pulley exists. As a matter of fact, no 1953-82 Corvette small block ever used a 3 groove pulley. However, some applications did use a 2 groove pulley in conjunction with a 1 groove pulley in a "sandwiched" arrangement. The only 1967 small block application that used this configuration was those equipped with K-19. So, there were pullies available that will properly "sandwich" to the 1967 2 groove small block pulley. All are GM-discontinued but I think most are available in reproduction. I have no idea if you could use a K-19 driver pulley for an aftermarket A/C driver application since I have no idea of what alignment would be required.

Other than the above, you would need to use an aftermarket 3 groove waterpump pulley and that would likely create other pulley alignment issues for you.

[Michael M.]

Re: '66 A/C Pulley

Peter,

If you have the '66 L79 with no power steering, you should be ok with the double pulley you have now. The only point of reference I have handy right now is the LI Corvette catalog. It shows a longer belt to replace the "idler belt" in the front of the double pulley. The rear belt goes to the alternator. They both catch the water pump as well. The part number they show is 59-31 (I don't know the chevy part #) and I'm not sure if the belt will fit correctly with the aftermarket compressor. I have the L79 with power steering and in that case you need the add-on pulley in the front because you have the alternator, PS pump and AC compressor and you need 3 belts. You should be able to look at it online in section 59 "belts".

If you do it, let me know how you make out. I thought about that myself.