[chevyguy_72]

Originally Posted by chevyrestoguy

If he's not interested in a Vintage Air style unit, then he is going to need to find an original evaporator assembly. You can find them, but they often come with the rest of the entire system and the seller may not want to separate it. These units are big, and they hang down below the dash, but if he wants a factory look to his truck, then it's one of his only options.

The factory set-up can be modified to work with later components, but you have to make a few changes. The original units used a throttle suction valve which doesn't work that great with R134, but it can easily be swapped out for a POA valve that's calibrated for R134. These original units used barb fittings, hose clamps, and a non-barrier hose, and they aren't what you want with R134. They'll work, but there's an increased risk for system leaks. You can weld on Bead Lock insert fittings to the evaporator ends (suction and discharge) and run the crimp style fittings with the o-rings and barrier hose.

There are options for the compressor as well. If he wants to look factory under the hood, he needs to run the big A6 style compressor. If he wants to upgrade to a better (smaller) compressor and stay with a v-belt, he can go with a Sanden or a factory R4 compressor from an '80s/early '90s GM vehicle. If he wants to upgrade to a serpentine set-up, there are many factory set-ups that work great and are available at nearly any wrecking yard. Just make sure to upgrade the water pump to a reverse direction pump because it spins backwards on a factory serpentine set-up.

I'm assuming that he wants to upgrade to R134? If so, I would suggest he choose a condenser that's designed for R134. The original R12 condensers will work, but they use a tube and fin design versus the R134 parallel flow design. Usually, the R134 condensers are physically larger, but that's not always the case.

If you do your homework, you can build a great working system using factory parts from the '60s to the present.

Thanks for the info... I really doubt he will want to go through all of that... I don't think its as much wanting to look factory and not having to weld up old holes in the firewall... thus ruining a factory AC cab...

a better idea might be to go vintage air but just cut out and bolt and silicone covers over those holes that could be removed if a future owner wanted to convert back to factory ac with minimal repair...
Thoughts on that approach?