rack and pinion question

Karsten (MyBad79) loaded some great info in the downloads section - under chassis & suspension. (Includes some part numbers as I recall.)

I've got some diagrams to build mounts - I can search out that were measured diagrams from some Speed Parts mounts.

Cheers - Jim
 
I did that conversion on mine. Not to bad at all. I made one mistake though and I made the center bracket about two inches too short. I bought more stee lto make it, just havent had a chance to do it yet.
 
I THINK I may have some diagrams still on file from my rack conversion, I may have uploaded them here, but I did my rack conversion winter 01-02 so it's been a while, the rack came from a '89 Grand Am, junkyard find of a new/fresh rack for 35 bux.....a welder buddy made the mounts, the one on the pass/right side is easy, the one on the driver/left side too two attempts, the input from column to rack was pieced up from junkyard parts from Lumina series mini vans....as I recall.....I took the universals apart, and pieced them together as needed to make up the linkage, it took only two universal joints and not 3 as with the kits.....so no need to support the intermediate joint....the trick is, I used the OEM tie rod ends, so no change on the suspension, just got a machine shop with the correct taper reamer to make the adaptor plate for the rack CTO.....my tie rods are 19 and 21" long, so not equal length, I should maybe have adjusted that center mount to make them equal, but I see nothing to gain for the effort over the years....

IF the sketches can't be found here, PM me and I will scratch around to see if they can be sent.....

:cool:
 
Yup, did it for not much $$$$ ... All new parts, rebuilt rack .... It was fine but it has developed some play, haven't had time to dig into this but I'm convinced the brackets that I built are rock solid, I'm suspecting the rack itself ....
Another thing: the manual rack from the Cavalier or GrandAm is 3.75 turns lock to lock - not all that great but very easy to turn.... I have a power rack with 2.5 turns lock to lock and will try that without the PS pump to see if that ferls better .... Not happening anytime soon but when time comes I will definitely start a new thread with more pics ....
 
Where did you get the rack from ?

All of the other cars I've ever driven here in Europe are rack and pinion. Can't remember I ever had one that developed play, other than at the joints.
 
I bought a manual and a power rack from Rockauto, rebuilt .... I guess it doesn't matter where you buy, these rebuilds are sort of a hit or miss ... Same with rebuilt calippers .... It's not like Rockauto rebuilds these , I'm guessing these are all rebuild in low cost countries .... Maybe the 10 year old that rebuilt mine had a bad day ....
 
A couple of questions after reading up on the subject :
- I see that the colums sticks out fairly long and so the angles to get to the rack maybe pretty sharp, causing issues. Don't want to cut the motor support and don't want to shorten the column either, what are the options ?

- any issues using different length arms when the rack is offset ?
 
A couple of questions after reading up on the subject :
- I see that the colums sticks out fairly long and so the angles to get to the rack maybe pretty sharp, causing issues. Don't want to cut the motor support and don't want to shorten the column either, what are the options ?

- any issues using different length arms when the rack is offset ?

No issues with the arms, the center link takes care of that - you can weld the center so that the arms (tie rods) are the same length.
For the input shaft: I didn't like the idea of having three U-joints so I cut the frame horn, after welding the half pipe in there it's stronger than it ever was so no worries here ... I don't see any other options, cut the mount, collaps the column and it's all good .... I still have to check what's wrong with my setup and why there's slop again. I don't want to blame the rack until I inspected everything else .... Although at this point I believe it is the rack ...
 
A couple of questions after reading up on the subject :
- I see that the colums sticks out fairly long and so the angles to get to the rack maybe pretty sharp, causing issues. Don't want to cut the motor support and don't want to shorten the column either, what are the options ?

- any issues using different length arms when the rack is offset ?

No issues with the arms, the center link takes care of that - you can weld the center so that the arms (tie rods) are the same length.
For the input shaft: I didn't like the idea of having three U-joints so I cut the frame horn, after welding the half pipe in there it's stronger than it ever was so no worries here ... I don't see any other options, cut the mount, collaps the column and it's all good .... I still have to check what's wrong with my setup and why there's slop again. I don't want to blame the rack until I inspected everything else .... Although at this point I believe it is the rack ...




Hey man, dunno if you aware, but those racks have an adjustment screw to push the rack into the pinion just a bit, that is the 'slop' adjustment, take a good look around the pinion input position and spot that bolt.....it's not much of an adjustment, turns wise, so be careful......:clobbered:
 
Hey man, dunno if you aware, but those racks have an adjustment screw to push the rack into the pinion just a bit, that is the 'slop' adjustment, take a good look around the pinion input position and spot that bolt.....it's not much of an adjustment, turns wise, so be careful......:clobbered:

Damn I had no idea ... That would be a easy fix .... Thanks !!!
 
Hey man, dunno if you aware, but those racks have an adjustment screw to push the rack into the pinion just a bit, that is the 'slop' adjustment, take a good look around the pinion input position and spot that bolt.....it's not much of an adjustment, turns wise, so be careful......:clobbered:

Damn I had no idea ... That would be a easy fix .... Thanks !!!

OH, forgot to mention, the center/straight ahead position gets the most wear, obviously, so when adjusting, make sure the tires are in the air, and you don't have any binding on the rack assy from full R to full L.....but that much should be apparent anyway.....it's the RACK version of the adjustment on our old stock steering boxes or the Jeep box fir that matter....

:drink:
 
YUP, loosen the obvious locking ring/nut and play with the center bolt a nudge at a time.....remember to go from side to side and make damn sure there is no binding.....:smash:
 
Yves,

Each of us makes some improvements with each generation of this project.

Using a double u-joint which can tolerate greater angular offset to connect the steering column to the intermediate shaft should allow you keep the column at stock length. The intermediate shaft will have to be stabilized with a bearing. They make oversize rod ends for this purpose.

In adapting the GM R&P to C3/C2 chassis the R&P housing mounts off center so the steering input shaft can connect. The center takeoff design of the R&P allows you the freedom to make an asymmetric center link so the tie rods can be the same length right and left. This also allows you the make the center link so that the inherent bump steer is minimized.

There are other project pictures in my earlier R&P posts.

Grampy
 

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can you give me the link ? And maybe a parts list ?

If my eyes are not deceiving me it looks as if the link is awfully close to the headers, almost touching.

Can I assume that the R&P makes the car steer like a modern car ? I'm used to European cars steering systems and never seem to get used to the vettes steering box.
 
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