I saw on NJ Craigslist a guy selling what he calls a 12/71 blower. The pics look like two 6/71 blowers to my untrained eye. Is that the case? Could one or both be converted to automotive use? http://cnj.craigslist.org/pts/4486416968.html
GMC made a whole series of 2 stroke diesels with that type blower. They were named by the size of the individual cylinders, like 53 for 53 cu in, 71 for 71 cu in etc. You could get engines from 3-53 (3 cyl X 53 cu in) to 12-71 (12 cyl X 71 cu in). Each one had a different supercharger but all were related, and of similar design. If that blower is off a 12-71 it looks like they took a pair of 6-71 blowers and hooked them together.
That's what it looked like to me too. They might be 6v71s ? How do you tell them apart? He's asking $300 for the pair which sounds cheap. I'm not in a position to get them myself :-( ...but maybe a HAMBer will want them.
Those blowers were made for a "V" style 71 series Detroit , they have no mounting flange on the lower part of the case. I have seen some adapted to automotive use.
They are 6V-71's. Easiest way to tell them apart is the double ribs on the side. 6-71's have single ribs, and a row of bolt holes along the bottom, where the 6V-71 "clamp" on with bolts that run through the slots between the double ribs.
As far as I know the biggest 71 series blower GM ever made was the 8:71. The 12:71 engine used two 6:71 blowers as shown above. GM 8:92 blowers are widely available in truck-bus junkyards if you want a bigger blower. Otherwise I believe you will need to go to the aftermarket foe a 12, 14, or 18:71 Blower. 18:71 shown here. this is 5 inches longer than a top fuel 14:71.
Depends. If you wanted to experiment around and they are not worn out, they would be as good a start as any. If you want to send them out to be rebuilt and put them on your car, you would be better off just to buy a blower.
Rich is right on. GM never made a single blower for an engine larger then the 8V-71. 71 Series Detroits did however come in V12, V16, and V24 (Yes Virginia, they made V24's) varieties. The 12's, 16's, and 24's all used a combination of 6 or 8 cylinder blowers. The blowers the OP posted are off a 12V-71. You should be able to get end caps for them, but the 6-71 blowers off the inline 6's, are much more desirable (and most would argue easier to work with) then the 6V blowers. 24V-71 for the record with 4 6V blowers on it.
the V series blowers can be adapted to hot rod use, but it's usually wise to start with an inline blower...makes life easier