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Ok, throughout my research, this post should cover most of the questions about the GrandAm rack and pinion conversion. I tried to get all of the major points from other threads and put them all into this one. I did this in a one car garage, with no heat :crazy: , lift, or special tools. The major power tools I used were a small Lincoln gasless MIG welder, Sawzall, and an angle grinder/cutoff-wheel. Patience and desire is a must, along with some fab and design skills. I’m only 18, so I’m sure you older guys (and gal) could tackle this project too. One thing to keep in mind though is that you do steer the car with this. So think the project through very thoroughly before tackling it.

I tried to take as many pictures as I could during this project, but I probably missed a few detailed shots. You should be able to get the idea of what I am talking about with the pictures I have though.
Before taking anything apart, I drove the front wheels onto a set of Rhino Ramps. (Along with jack stands under the frame) This made it so that I could take measurements for things like tie-rod length and position with the suspension at ride height, and still be able to get under the car. (barely)
First thing I did was disassemble the old system.
It is helpful to have another person to pull out the box – I couldn’t get my headers (Hooker sidemounts) out without taking the box out and the box wasn’t coming out with the headers in :toilet . So I had the headers un-bolted, and moved them enough to get to the nuts securing the box to the frame. Once unbolted, I had another person hold the box from the top of the car while I was waiting to catch it from underneath the car. It’s nice to have the other person there, so they can slowly let the box down to you, rather do it yourself and to have it fall on you, because the weight of the box can surprise you. I also had to pull the clutch Z-bar to get the headers out. It also just gives more room to work, even if you can take the headers out with the Z-bar still in.
I pulled the old system out as one unit; I just unbolted the idler arm from the frame, and the tie-rods from the spindles.
Still haven’t figured out why my camera always takes blurry pics, but you get the idea:


Nice and roomy now that everything is out:


I bought a remanufactured rack for a 1992 Pontiac GrandAm from AutoZone for about $160, that’s including the $80 core charge
I got the sport steer (2.5 turns lock to lock I believe), non variable assist rack AutoZone P/N 6449
The remanufactured racks DO NOT come with the brackets OR tie-rod bolts. I went to a junk yard and had them pull a rack and made sure they got the brackets to mount the rack. One thing I forgot to do was have the junk yard include the tie-rod bolts. They charged me $50 for the rack and brackets. I went to a Pontiac dealer and they told me that GM no longer manufactures this bolt, so they have to special order it from some warehouse - $28 for the two bolts :thud: (AutoZone didn’t care that I brought them a standard steer rack back, although I didn’t tell them I brought them a different one)

Here is the driver’s side clamp for the rack. This holds 90% of the lateral forces put on the rack when steering the car. Stock, they have holes sized for the bolt on the left. That just doesn’t look strong enough to me. There is plenty of meat on the bracket to drill it out for a larger bolt:


I started messing around with positioning of the rack, so I put some jack-stands under it to hold it in place while looking for a good final position. I have rope holding it up in this picture so I could move it around easier. I tried to get it tucked up as high as I could:


I chose to cut a notch in the motor mount, so I could tilt the rack input more horizontal to prevent U-joint binding: (With the box and clutch linkage out, it is surprisingly easy to get a sidemount header in place by yourself if you have the car high enough. Having the header in is essential for positioning of the rack input with the U-joints as is gets pretty close)



If you look closely at that last picture you will notice that I shortened my column shaft. At stock length, it is impossible to use only two regular U-joints. You should be able to hammer on the end of the shaft and it should go in as far as you need. (DO NOT hammer directly on the end of the shaft; use a block of wood or something to protect the splines at the end) If it won’t budge, you can refer to my “Shortening the steering column” thread. There are a few pictures in there that should help with the disassembly of the column (already out of the car).
I used flaming river U-joints with a DD shaft on my car. The steering column is 1”-48spline and the rack is a 17mm DD.
Part numbers for the ones I used: (summit racing)
FLA-FR1712DD – 1”-48 + ¾ DD
FLA-FR1759DD – 17mm DD + ¾ DD
FLA-FR1850 –18” ¾ DD shaft –just enough to mess up once
This was the most expensive purchase of the whole project at around $180

One thing I never heard other people mention was the hard-lines that run across the rack. They hit the oil pan, and came close to the tie-rod bracket in the position I had the rack, so I straightened them out, and re-routed them to the lower rear of the rack. You can cut off the fittings on the passenger’s side of the rack if you have a double flaring tool so you can make the lines shorter if need be. I used a compression fitting on one of the lines (1/4” line) to make it longer:


For the tie-rods, I had just done the VB&P performance upgrade last winter, so I kept my MOOG ball-joints at the spindle end, along with the HD tie-rod sleeves. For the rack end, I used a HD chrome moly heim-joint with a ½” hole and 5/8” 18 thread (1 left and 1 right-hand thread)
Part numbers (speedway motors)
91002126 – RH thread
91002326 – LH thread
These were around $45



When I had mine in the final position, I went over this little checklist to make sure everything will work in the position I had it.
-Do the U-joints bind?
-Do you have header clearance?
-Can you access the pressure and return lines for the pump?
-Do the hardlines contact anything that could chafe them over time?
-Does the front driver’s side tire clear the rack under full turn? (My 245/45/17 with a 4” backspace TT2 wheel is about 3” from the rack at full turn)
-Does the suspension come in contact with anything under full compression/droop?

Now that everything was double checked and in alignment, I started to make some brackets. I used 1”x1.5” tubing with a 1/16th” wall thickness. The rubber mounts on the rack measure 15/16”, so 1” tubing fits nicely. I braced the bracket with 1/8th” steel plate.
I welded nuts to the inside of the tubing, and boxed in the whole thing: (same goes for the passenger side)


All of my brackets are welded to the frame; I don’t plan on returning it to stock. Although, I have seen a few nice ones (not steeroids) that were bolted to the original box mounts and the four holes on the bottom of the frame rail.
On my bracket, there is a plate that is welded to the inside of the frame rail (similar to the spot the box was mounted) and is welded to the mount in the above picture. Here it is, everything here is 1/8th” steel




Next is the passenger side bracket. I made the same style bracket out of my 1x1.5 tubing and 1/8” bracing:


Hooker side mounts make it hard to have anything bolt up using the stock idler arm bolt holes, so mounting the bracket from the inside of the frame rail was not an option in my case. My bracket is welded to the bottom of the motor-mount, and the frame rail:

 

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Discussion Starter #2 (Edited)
When I notched the frame, it allowed the rack to move more forward on the frame, which made it easier on the U-joints, but makes it very tight for the tie-rod bracket. I don’t particularly like the way the steeroids bracket is designed, plus to make it as strong as I would like, it would not allow the bracket to fit in-between the lower control arms and the rack. I went with some more square tubing (1.5x1.5”, 1/8” wall) to connect the two tie-rods together. I welded some 1/8” plate on the ends where the bolts go through to reinforce it:




Here is that bracket completed with the mount that bolts it to the rack, and painted:



I placed that bracket so that it made the tie-rods as parallel to the control arms as possible, and also the same pivoting length to reduce bump-steer as much as possible:



Next, I painted everything and started final assembly. Here is the car at ride height. The passenger side bracket is the lowest point of the whole system, and it is barely lower than my headers:


Driver’s side is a little higher than the headers (now everyone can see one of the many reasons my car is a good 10-footer :( :


With the car on the ground (concrete floor) I had a friend turn the wheel lock to lock while I watched the brackets. There was absolutely no flex in both directions, on both brackets.

Here is the car up on my Rhino Ramps, I put the rack as high as I could, and I believe it’s only a little bit higher than the Steeroids unit:


Here is the steering shaft showing clearance with the headers:


Overall, it was not as hard as I thought it would be. At some points during the fabrication I wondered what I got myself into, but I allowed myself to walk away, and rethink what it was I had to do. If you don’t have a lot of patience, this may not be for you. I learned a lot about steering systems and design, along with some fabrication techniques. As of now, I don’t have any power steering parts hooked up yet, but to be honest, it seems easier to turn the wheels when the car is stationary than my old steering box setup. Just steering it back and forth on the garage floor, I can really feel a difference in how smooth and responsive it is compared to my old sloppy box. I am yet to take it for a test drive because of some starting problems :bang , but hopefully I can get it sorted out tomorrow before I have to go back to school. Anyway, I hope you enjoyed the pictures and hope that this will encourage people who are skeptical to make the kit themselves to go out and do it. :thumbsup:
Also, here is my total cost list (not including steel)
- Remanufactured steering rack…….$165.00 ($85 core charge included)
-Junkyard rack and brackets…………..$50.00
-Various grade 8 bolts………………..~~$10.00
-Tie-rod bolts ………………………………...$28.00
-Heim joints……………………………….…..$48.00
-2 U-joints and steering shaft………...$181.00
_____________________________ - $85 core charge

TOTAL COST= $397.00 :partyon:
 

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Very Nice Write up.
 

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DC Pit Crew
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thanks for taking the time to put this thread together. These kinds of pictures are pretty helpful for those of us considering the project. One question on the center tie rod bracket: Did you use any sort of spacers to sandwich the heim joints between the walls of the tube? Or can the heims slide on the bolt?

Also, what are the tie-rod bolts you refer to? It looks like you used standard grade 8 bolts for the inner mounts on the tie rods. Do you have any pics of the center of the tie rod bracket where it mounts to the rack? That's one area that I still don't have straightened out in my head.
 

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Discussion Starter #5
One question on the center tie rod bracket: Did you use any sort of spacers to sandwich the heim joints between the walls of the tube? Or can the heims slide on the bolt?

Also, what are the tie-rod bolts you refer to? It looks like you used standard grade 8 bolts for the inner mounts on the tie rods. Do you have any pics of the center of the tie rod bracket where it mounts to the rack? That's one area that I still don't have straightened out in my head.
Yes, there are shims above and below the heim to prevent it from sliding. the tierod bolts im referring to are the bolts that mount the tierods to the rack on a grand am. it is kind of hard to describe them.
These two silver bolts here that mount my bracket to the rack:

I edited the original post with this pic, hope this clears things up
 

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DC PIT CREW BOSS
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Great write up. This is true hot rodding at its finest:thumbsup:
 

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Discussion Starter #8
Finally got the car started today, and all i can say is WOW. it is a whole new car. I do not have the PS pump hooked up, and it is still easy to turn, even at slow speeds. I can do a K-turn with no problem, and driving around at anything above 10mph, you would never know its not power steering. parking lot speeds requires minimal effort compared to what was needed for my box. from this little test drive around the block, i would like to leave it manual steering, unless it is a requirement for the rack to stay lubricated with the pump.
I do have summer tires on right now (245/45/17 Nitto 555 both around 28-29psi), and im sure in the summer i will notice a difference in how easy it is to turn at slow speeds, but this is significantly easier than my old box.
This is the quick ratio rack too :D
 

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DC Crew
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Great write up. This is true hot rodding at its finest:thumbsup:
I agree 100% :thumbsup:

At 18 YO you are and are going to be a force to be hard to keep up with! :cheers:

Nice writeup :thumbsup:
 

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DC Pit Crew
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Finally got the car started today, and all i can say is WOW. it is a whole new car. I do not have the PS pump hooked up, and it is still easy to turn, even at slow speeds. I can do a K-turn with no problem, and driving around at anything above 10mph, you would never know its not power steering. parking lot speeds requires minimal effort compared to what was needed for my box. from this little test drive around the block, i would like to leave it manual steering, unless it is a requirement for the rack to stay lubricated with the pump.
I do have summer tires on right now (245/45/17 Nitto 555 both around 28-29psi), and im sure in the summer i will notice a difference in how easy it is to turn at slow speeds, but this is significantly easier than my old box.
This is the quick ratio rack too :D
that's really good to hear. So did you have manual steering before? I have manual steering right now and would rather not add the pump and lines if I don't have to. I don't mind not having power steering right now, so if the rack makes it a little easier then I should be fine.

Dang it you're getting me all anxious to do this to my car now. I don't want to weld on the frame though, so I'll have to get a bit creative on mounting options.

Thanks again for the pics :thumbsup:
 

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Discussion Starter #12
that's really good to hear. So did you have manual steering before? I have manual steering right now and would rather not add the pump and lines if I don't have to. I don't mind not having power steering right now, so if the rack makes it a little easier then I should be fine.

Dang it you're getting me all anxious to do this to my car now. I don't want to weld on the frame though, so I'll have to get a bit creative on mounting options.

Thanks again for the pics :thumbsup:
Yes, my old box was manual steering. If you dont want to weld on the frame, there are plenty of bolt holes that you could mount the bracket to on the DS. 4 holes on the bottom of the frame, and obviously 3 for the box. the pass. side might be a little tricky, especially if you want sidemount headers.

Nice work on the rack setup. You will really enjoy that mod. I personally would add the PS pump to the system. You may not have to run the stock corvette pump but could probably come up with a smaller pump with a separate reservoir.
I would really like to stay with the manual steering. i love the way it feels now, and dont mind the little bit of extra effort required when going slow. steeroids says its ok running it manual, as long as you keep some fluid in it to lubricate it.

Thanks for all the compliments guys :thumbsup:
 

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Hey, have you had any problems with your setup since you have
installed it? Is there any thing you would change? What brackets
did you receive from the junk yard, are they just the U-clamps? I am
hoping that I can start this soon so I think I'm going to buy all
the parts in the next day or so, I hope I have the time to get this done.

Thanks for your help and all the photo's you have posted.

Riggs.
 

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Discussion Starter #14
I have about 2000 miles on the setup so far and Ive only come across a few little things that I would have changed had I known about them.
The main part being the brackets. It was said that bolting the brackets to the frame is stronger than welding. If I knew this before it was all said and done I would have gone for this route. Its tricky to get a nice weld on the frame. Ive had no problems with my welds so far (and I put alot of stress on them and the rest of the rack setup) but If it is stronger to use the existing bolt holes on the frame then why not do it.

Next was the bump-steer calculations. If you plan do do some high performance driving, then definitely look up how to calculate tie-rod location/length. I got some bad info on how to get this length/location, and I ended up with more bump-steer then I would like (not bad, but I didnt want any)

Yes, the brackets I got from the junkyard are the U-brackets.

One of my favorite mods to my vette so far :partyon:
If you have any questions, dont hesitate to ask
 

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Great write-up. I remember when I first signed
on to the sight we talked about you installing
the Rack and Pinion steering, and you said it was
really hard, now I can see why. Looks to be
a pretty decent job. How is it holding up?
I did quite a bit of work on the 81, but nothing that extranious. Again, nice job. Great pics.. Larry
 

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Next was the bump-steer calculations. If you plan do do some high performance driving, then definitely look up how to calculate tie-rod location/length. I got some bad info on how to get this length/location, and I ended up with more bump-steer then I would like (not bad, but I didnt want any)

Yes, the brackets I got from the junkyard are the U-brackets.

One of my favorite mods to my vette so far :partyon:
If you have any questions, dont hesitate to ask
Can you share with us what the calculations for the bump steer should be? Nice write up and a very well done project. :cheers:
 

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DC Crew
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Very nice! Great write up...great documentation. I love the minimal U-joint input shaft. The Steeroid and Shark Attack Rack are very hard to get to turn smooth due to the third joint. I'm fighting that now in my current Steeroid rack on the current project.


MRVETTE inspired me to build one too. I have installed several of the store bought ones and wanted to try something different.

I like using OEM parts where I can - which includes the tie rods. I found you can use TWO passenger side Grand Am tie rods instead of after market racing parts.

As far as bump steer, the perfect solution is to have the tie rod run in perfect geometry with the A arm travel - that way there is no difference between the suspension load and tie rod squat/flex.

If you are not going to be able to mount them in perfect alignment, the next best thing is to make the tie rod as LONG as possible by having it pivot as close to the center as possible. This is the idea on the GM front wheel drive cars that use these center take off racks...and the same idea I decided to pursue. However, the Vette is a tad wider than a Grand Am, so it still required an extension bracket in the center to both CENTER the tie rods, and allow them to reach while keeping them equal length.

Here is my write up.

http://mcspeed.homestead.com/Rackinstall.html

 

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This should be a sticky in the c3 tech info this is just the kind of stuff the do it yourselfers need to see.
 
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