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Power steering conversion 70 Road Runner

Eric F

Active Member
Local time
11:53 PM
Jan 22, 2023
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Atascadero California
I’m doing a power steering conversion on my 70 Road Runner. I’m using parts that came with the car. The pump I believe maybe from a later vehicle as the pulley is solid not the 3spoke one. But bolts up to the block. The power steering gear is my hum? The old manual box has a 11/16 x36 input with the 1 1/8 output.
The power gear is 5/8x36 input 1 1/4 output. The casting number on the gear box is 3643311. I inserted a picture of the box. I googled the casting number . It came up as a 73 and later A body box? Another forum stated use can use a later pitman arm? I don’t have an issue buying the correct box if this one is wrong.
Atascadero? Welcome from Osos! BTW, the welcome wagon is where you introduce yourself, what you have plus pictures. This question would go in the brakes, steering and suspension section. The steering box is fine but the shaft in the column for manual steering is longer, pitman arm for the later box is easy. Show some pictures of the pump stuff you have.
This the only picture of the pump I have. I can go take better pictures this afternoon. I did just post on the welcome wagon right after I posted the steering question.

Welcome to FBBO from NorCal Sierras, 200 miles east
Plot thickens I found this Mopar part# on the tag on the steering gear. I’m really starting to wonder what I have.

If you know what the pump came from, start with that for line selection. If it's a no go, you'll need to determine the fitting sizes of the pump and the box. Do you have a contact at GEM or one of the other stores up there? Since the two units are out, take them there so you can figure out what the fitting configurations are. 5/8 or 11/16 inverted flare? SAE flare? Etc. Once you are armed with that info, look in a p/s hose catalog going for Mopar applications from 70 on. Get pressure line numbers for b/rb engine then look in the back of the book where they are listed by part number and fitting configurations. If I still worked at Westside in SLO, I would do that easy. I would highly recommend not calling there for this info as the two counter gents can't be bothered with a task like this.
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