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fasteddy_1947 02-17-2013 05:07 PM

Rack and Pinion question
I have a mid '80s Cadillac rack and pinion I want to put in '39 chev. The pinion tower (and I assume the power steering valve) has a pair of wires (red one and green one) w/connector that probably went to the computer in the car it came out of. Problem is I have no idea what they are for, or if the rack and pinion will work without a computer hookup. Have started building the mounting brackets for the steering, but I might just have unusable junk and need to go junkyard crawling to find steering set-up I can use. Anybody got any good ideas? Any help is always appreciated, and I don't mind a little ribbing about not knowing these things. Most my cars are older than I am, and back then they didn't have computers and such. (they didn't even have seat belts, if you can imagine that). Thank you. :D

cal1320 02-17-2013 05:11 PM

No idea on the wires, but are you mounting it to a straight axle? If so, I've been down that road and will share what I know about it.

timothale 02-17-2013 06:23 PM

more info
What suspension do you now have in the front. Chevies of the late 30's early 40's used I beam straight axles, Knee action with coils, and also the double A arm more modern design. There are kits to bolt in mustang II fronts, the frames are a little different for different stock suspensions used. and what type of rack does the caddy use , GM used both center pivot and conventional shorter link racks in those years. There is a Wiki article here on hotrodders about upgrading the larger Gm cars of that era, buicks olds pontiacs, most parts are different but will give you some ideas.

fasteddy_1947 02-17-2013 07:37 PM

yes, putting on straight axle. Got the geometry figured, and engine and exhaust manifold clear when I move the steering wheel on the firewall looks like this one might just fit. couldn't do it with pitman arm and linkage. steering box takes too much space and would need all kinds of u-joints, and extension rods and supports to match it to any steering wheel, but squeezing the rack and pinion under the engine and mounting to the axle (and also have to shorted tie rods, no biggee) seems to be ideal solution. Can't go with the mustang front end (simply can' afford it or the shipping). Just need to find out if this set I have needs computer control to operate. If I can't use it, then try something else. Nothing I like better than spending day in local junk yard and pulling my tool bag around on one of those little carts (except this yard, all the carts got at least on bad or broken wheel) and the selection is almost unlimited. Mainly dont want to finish welding up this mounting bracket I made for it and find out it won't work without computer. I suspect that the green and red wires and connector control the direction of flow to the power steering cylinder. Can't find the info anyplace. A mechanic told me it don't make any difference, but I don't think I worded the question right. Do appreciate all the help, and not afraid to scrap it and start over (like that never happens) but thought someone might just happen to hae run into this before and would know. Thank you

fasteddy_1947 02-17-2013 07:45 PM

The caddy uses the center mount with the tie rods and ends. Reason I chose it was the tie rod ends are attached behind the steering pivot point (the kingpins) and I don't have to go over anything (exhaust manifolds, cylinder heads) or outside the frame to connect to steering wheel. I have a rack out of a camaro also, but it attaches in front of the kingpins and would steer backwards unless I turned the steering wheel upside-down or always remembered if I want to turn right, I have to turn left.

cal1320 02-18-2013 08:03 PM

Here are some pics as to what I used.

95 Saturn rack with factory steering joint, Borgeson telescoping steering shaft, 3/4''DD x 1'' DD joint,
5/8''LH tie rod ends (for both sides), 5/8'' LH and 1/2''RH tube ends(2 each), 1'' .095 wall DOM tubing, shorten inner tie rods and rethread to RH 1/2-20. LH tie rod ends and RH tie rod threads allow easy setting of toe and centering of steering wheel

Mount rack, install outer tie rod ends, install inner tie rods, align front tires, cut DOM tubing to fit between. Have them welded professionaly if you cannot do it. I cut the original column below the firewall, Lathed a bearing retainer and used a 3/4'' flange bearing. (These retainers and bearings are sold in the aftermarket for a 69? Chevy truck) Milled a DD on the end and attached the u joint to it. Telescoping shaft allows the axle to move without binding. I disassembeled the shaft and removed the tension spring inside to allow easier movement of the shaft. Keep it well greased. Make sure the shaft has enough travel to prevent bottoming out, or over extending. Your shocks are the limiter for extention. NOT the stop bolt in the shaft. There was a slight loss of turning radius, but not really noticeable. The power steering really makes up for it.:D
You may want to add some caster shims for more positive caster if you like.

fasteddy_1947 02-18-2013 11:52 PM

OK, all helpful. Got the lowdown on the wires from the pinion housing from the Cadillac dealer. Computer gets info from sensor in pinion box and determines if you are running straight or turning, and if running straight, if the steering wheel is correct position, or you may be ready for an alignment. Has no affect to the operation of the steering rack, just a little red warning light comes on if computer thinks it can get you to spend some money at the daler getting your caddy aligned. Went ahead and welded up my mounting for the rack started to shorten the tie rods. will finish that tomorrow, maybe. Never woulda thought about telescoping shaft. was thinking tilt shaft for the angles, but the telescoping would also cover the distance to the firewall. Coming right along. I thank you all for the helpful suggestions. Some I can use, some not, but it sure is nice to know that people out there actually know this stuff right off the top. I am usually in trial-and-error mode. If this don't work, try something else. And I normally have plenty of time to rethink it while I'm saving up the money to start over with different plan. You guys that been there save me a lot of time and money, and frustration. So, thank you again. :D

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