55 Buick - water pump upgrade for AC?

**McGuireV10** · 08-18-2008, 11:10 AM

We recently purchased a '55 Special. It runs well (we drove it more than 900 miles home from PA to FL), needs a new interior and some other minor stuff.

I plan to install AC (most likely Hot Rod Air) relatively soon, probably locating the compressor where the generator is now, and installing an alternator on the other side (power-steering side). I know that'll be loads of fun, but it seems to make the most sense.

I've read that the AC-equipped cars had a different water pump (5 impellers instead of three) and were driven at a different rate (faster, I assume). But the same article said the three impeller pump "works better most of the time" without really explaining what they meant.

I do plan some cooling upgrades -- a new radiator and an electric fan with a thermostatically controlled switch.

I'm trying to decide whether I should also consider switching to the AC-style water pump, assuming I can find one, or whether a new radiator and fan will make enough difference.

Any opinions would be appreciated. Thanks!

**gishmonster** · 08-20-2008, 01:22 PM

HI
One other consideration for the cooling would be to try and find a 6 bladed fan. They were optional equipment and I have only seen two of them go up on EBay in as far back as I can remember. They must have had some use for the cooling problems or they would not have had them.
Good luck
Kerry

**Airy Cat** · 08-20-2008, 04:09 PM

For those Buick nuts that are looking for the correct battery (Group 60) for their late 50s to early 60s, I have found a very close replacement.
It's a Commercial Heavy Duty (Group 30H) 550 CCA.
6.5" wide, 12.75" long, 8.5" high. These measurements are approximate, but it does fit the tray and hold down clamp of my 1955. You will need to use longer hold down bolts.

**McGuireV10** · 10-29-2008, 07:04 AM

Originally Posted by gishmonster

HI
One other consideration for the cooling would be to try and find a 6 bladed fan. They were optional equipment and I have only seen two of them go up on EBay in as far back as I can remember. They must have had some use for the cooling problems or they would not have had them.
Good luck
Kerry

I had forgotten you mentioned this. I came back to the thread to post that I checked eBay for a 5-impeller fan and instead found a 6-impeller... and then I checked RockAuto.com and found that they have 6-impellers in stock all the time for less than $50.

So now the question becomes, how and where do I find a smaller pulley to drive it at the higher rate?

And I do wonder what they meant about the 3-impeller working better. Although I'm guessing they may not have been talking about an AC car since it was mainly a performance-build-oriented article.