Installation of Steeroids in a 1977 Corvette C3
Are you tired of the leaky steering control valve and/or steering cylinder on your Corvette? Are you tired of the 40+ year technology of your C3's steering system. One of the nicest upgrades that you can do for yourself and your car is to convert your original steering system to a modern rack and pinion system. This conversion is much easier than you think. While there are a couple of different kits available to do this, I went with a Steeroids kit. SpeedDirect have been continually upgrading these kits with stronger brackets and components and they stand behind their product.
The kit includes all the components that you will need. The kit is much lighter than the original components so your car will experience a weight loss which is always good. The step by step instructions from SpeedDirect are excellent and with any mechanical abilities at all, you will be able to install this kit.
The first step is to remove the old steering system. The only component that you will reuse is the power steering pump. It should be noted here that the C3 power steering pump produces about 1300 psi and the Steeroids rack unit likes about 1000 psi. The extra pressure can lead to excessive response and touchy Steering. Borgeson offers a pressure reduction kit #899001 that allows you to adjust the internal bypass pressure of the P/S pump. I did not install this kit and I am happy with the steering response. If you decide to install the pressure reducing kit here is a link to the install.
Removing the old steering system is relatively easy. I basically dropped all my steering linkage in one piece. I disconnected the power steering hoses from the pump (2 hoses), the pitman arm from the sector shaft (puller required), dropped the two tie rods at the wheels (pickle fork required), disconnected the idler arm from the frame (2 bolts) and dropped the steering cylinder bracket (4 nuts). You can now fold the old assembly up and pack it in the box your Steeroids kit came in. The only thing left to remove is the old steering box. Remove the top bolt that holds the 'rag joint' to the steering column shaft. If this is an original bolt, you will need a 12 point socket. You can separate the clamp with a heavy screw driver to make it easier to slide off the spline. Remove the bolts securing the steering box to the frame and carefully pull the box forward off the spline and down. Replacing small parts can be tricky if you have poor eyesight, and don't wear glasses, or haven't had Lasik correction surgery. Any Lasik Austin professional can give specifics about the procedure and who is a candidate for the surgery.
As I have already mentioned, the Steeroid instructions are excellent. I am not going to quote all their instructions here. However, I am going to cover the basic installation procedure and I will throw in a couple of tips that may make your life easier. Before you start, make sure you check that all your hardware and bolts came with the kit. Check and make sure you have left and right threaded link joints (1 of each) and left and right threaded tie rods (1 of each). I had 2 left link joints. A quick call to SpeedDirect had the correct joint on its way.
Before you start, make sure you clean up the spline on your steering shaft. Also, this is a good time to check the lower bearing in your steering column for excess play. If there is any play in it at all, I recommend you replace the bearing. The bearing is inexpensive and an easy 10 minute replacement at this point. You might also want to clean up the areas around the old steering box and also the area around the old idler arm as you will be installing brackets in these areas.
You are now ready to start. The most important thing in the installation is to pay attention to torque specifications and use Loctite when instructed to do so. I assure you a sloppy installation will not work and remember, this is your steering system that you are playing with and your safety depends on it working properly. After a few miles on your new setup, you are going to recheck all your work just to make sure everything is secure.
You will be installing the brackets first. It does not matter which side you start with. Make sure you follow the instructions and check the diagrams to ensure you are installing the bolts in the correct direction. Once both brackets are installed you are ready to install the rack. Make sure you have installed the steel plate on the rack, with the washers between the plate and the rack and that the plate is orientated properly (link joint connections on top). Don't forget the French lock under those two mounting bolts. You will notice that the spline on the pinion comes very close to the left motor mount support. However, this is deceiving and after the rack is clamped to the brackets, there will be sufficient room.
The next step is probably the more time consuming one and probably the most critical as it needs to be done correctly. That step involves the installation of the universal joint connection system between your steering shaft and the pinion on the rack. There are two things here that you can do that will make your life a lot easier. You should determine the midpoint of the rack and you can do that by turning the pinion until it locks up in one direction, turn it back until it locks in the opposite direction while counting the revolutions of the pinion. Once you know the number of revolutions lock to lock, divide that figure by two and then turn the pinion back until you are at your calculated half way point. The second thing you need to do is make sure your steering wheel is centered. If your steering wheel has a locking column, that will come in very handy to maintain centering. To verify that your steering wheel is in the centered position, just check to ensure the flat spot on the end of your steering shaft spline is on the top when you are looking down on it.
Having completed the centering procedure will ensure that your signal light cams will operate correctly and your wheel alignment will go more smoothly. You are now ready to install the universal assembly. The ends of the joints are different so you will not get them on backwards. The joint for the steering shaft has the flat side and is the double joint. You can slide that one on. Install the support joint very loosely making sure you have one nut threaded on before you put that joint through the hole in the support bracket. Put the lock washer and other nut on the back side of the joint but do not tighten it. You can now push the double splined rod through the support joint and into the double universal joint. Push the other universal joint on the bottom spline and now orientate the joint so that you can drop it over the spline of the pinion on the rack. You may need to push the support joint into the bracket in order to get sufficient clearance, but you will eventually find a right combination. Now that you have the joints installed, you can tighten the bottom joint using the set screws and nut locks provided. You can also tighten the other locks as well, although you may be adjusting those later. Semi-tighten the nuts on the rod support.
(Note: With some installs, there is a clearance issue between the motor mount support and the rack splined joint. It may be necessary to grind off some of the mount support. Be sure and check this closely).
You are now ready to check for any binding in the universal joints. It is critical that you have a smooth rotation through 360 degrees of your steering wheel motion. If you have any tight spots, follow the Steeroids procedure for correcting the problem. In most cases, moving the double joint down on the steering column spline will resolve any tightness. Once you have this resolved, tighten all set screws and the support rod nuts. Recheck your steering to ensure that it is still smooth.
You now only have a couple of things left to do. Install the two link joints on the rack. Make sure you put the correct threaded link joints at the location specified in your instructions. Use loctite when instructed to do so. Ensure your rack is still centered and install the tie rod joints to the adjusting rods. Make sure you have equal thread on both the link joint and tie rods. With your front wheels running as straight as possible, install the tie rods. You will notice some spacers that came with them. Read the documentation that came with your kit. These spacers are used to change the angle of your linkage to compensate for what is called 'bump steer'. I adjusted the angle on mine so that the rods are parallel to the ground when the weight of the car is on the wheels. I have no problems whatsoever with this setting.
The final step involves the installation of the power steering hoses. Make sure you have the 'o' rings on the fittings that connect to the rack. You might want to leave all connections loose until you have all hoses connected and orientated where they will not come in contact with other moving parts. Once you are happy with the fitment, tighten all connections. Before you crawl out from under the car to add fluid to the power steering pump, recheck all your bolts and nuts to ensure you have not overlooked anything. Add the fluid and bleed the rack by following the Steeroid instructions.
Congratulations! You are now ready for a test drive. I think you will agree that this setup is a major, major improvement over the original setup. On a final note, if you consider the cost of replacing the original steering components on your car versus investing in a rack and pinion kit, the benefits of the kit will far out weigh the small difference in costs.
Below, you will see some pictures of my install and most are self explanatory. I now have had my kit installed for a year and I have had no issues with it whatsoever.
The completed installation
Looking down on the universal joint setup between the steering column shaft and rack.
Looking up on the universal joint setup between the steering column shaft and rack.
Driver side view from under the rack and bracket
Passenger side view from under the rack and bracket
Driver side view behind rack where universal joint connects to the pinion
Passenger side view of bracket bolted to frame where idler arm was previously bolted
Driver side view of tie rod and link connection, notice spacers between tie rod and spindle arm
Another view of passenger side bracket looking front on