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Front Suspension. Starting with the Right Front.

Right Front Suspension with the wheel off.

Alright, Christmas day and I haven’t even started my wish list yet. For a racer, Christmas is just one more working day in the off season to get your car ready for the next race season. The clock is ticking and the season will be here before we know it. Although we haven’t really decided which division we are going to be running in next season, we can get a start on some of the systems now by checking parts and replacing the damaged components that are common between both race divisions (sport mods and IMCA mods).

Because it is Christmas day, I have to be quick and get into the garage to get done what I can while the family is absorbed checking out their freshly opened gifts. If I spend too long in the garage, and my absence is noticed……I just might have to move into the garage. So I decide to limit my inspection to the Right Front Wheel.

I start by jacking up the right front of the car and placing a jackstand under the R/F corner. Next step is to remove the right front tire to give me access to the hub. With the tire off, I get a better look at what I am dealing with.

I’m safe so far. No one has noticed that I am missing from the house so I can keep moving forward on the dissassembly. With the tire off, I can clearly see the spindle, hub, shock, spindle saver and spring. Nothing really alarming yet.

View of the inside of the Spindle with the tire off. Notice the spindle saver between the lower ball joint and tie rod mount.

I give the brake caliper a quick check and then remove the hex head retaining bolts. Because I don’t want to open the brake system yet, I support the caliper to the frame and leave the brake line attached. The next step is to remove the hub to check out the hub, bearings and rotor. Very quickly I remove the dust cover, then the cotter pin and finally the hub retaining nut. The hub comes off of the spindle very easily and the inner and outter bearings and races look pretty good. They even show the signs of fresh grease packed around them which is a good sign that the previous owner kept up with his preventative maintenance. With the hub and rotor off, the rest of the components can be checked a little closer. Right away I notice some abrasion on the lower A arm. The outside area just outside of the lower ball joint has been grinded away, and not be a grinder. The brake rotor shows signs of rubbing against the lower A-arm.

Lower A-Arm with ground off outer lip. The rotor had been rubbing against the A-arm when the spring and shock were compressed.

So it’s clear that I will need to make some changes here. I don’t have too much time to dwell on it now, I still have more components to remove before my wife notices that I have disappeared. I pull the shock absorber off by using the quick release pins on the top and the bottom. The right front shock is a Pro Shock WB 753.

Front shock absorbers are critical to the Modifieds suspension and steering. I really like the quick disconnect pins for removing and replacing the shocks quickly, but they need to be shimmed so that there is not a lot of slop in the shock mounting. Shock mounting is absolutely important in the effectiveness of the shock. Ideally, the shock should be mounted just behind the lower ball joint on the A-arm, and to the frame where the shock angle will fall between 10-20 degrees from vertical. I try to shoot for the middle and build the upper shock mount where the shock angle is about 15 degrees from vertical. At normal ride height, the shock should be resting about about half of it’s normal travel. The shock should never be allowed to bottom out or reach the end of it’s travel at the top end.

Shock Absorber mounting with quick disconnect pins. These make changing shocks at the track for suspension tuning, a quick and easy adjustment.

Everything is looking good so far. A little rubbing on the A-Arm by the brake rotor, but the shock and shock mounting looks good. The 753 designation on the shock tells us that it is a 7 inch shock with 5 valving in compression and 3 valving in rebound. This is a common shock to use on the right front on a flatter track that is a little bit slick. This valving set up allows the weight to transfer quicker from the right front to the left rear as the car exits the corner. Under this condition, the car will have better forward bite and will be a little tighter on exit.

Ok. So I am still in the clear. No one has noticed me missing yet, so I can keep taking parts off and checking them out.

Next step is removing the spindle from the car. Using a ball joint separator, removal of the upper and lower ball joints come off very easily, and most importantly, quietly. If I would have used a “pickle fork” to separate the ball joints, my work in the garage would have been heard inside the house. Using the clevis type ball joint separator, the job went quickly and virtually silent.

Using a clevis type ball joint seperator to remove the tie rod joint, upper and lower ball joints. Notice that I have left the nut on the end of the threads so the tool would not damage the end thread.

The spindle came off with no problem and I checked it over for any problems. The spindle has a casting number of 459756 RH, which is a 70’s G body spindle. These may not be the best choice in spindles but they are common use in the modified divisions with metric chassis. With the spindle off, I spot a problem with the ball joints. Both the upper and lower ball joints are bent. This also is a common problem. Racing is tough on parts, and ball joints are manufactured to be mallable. That is, they will bend first to prevent other components from breaking. That’s actually a good thing.

Lower Ball joint with a bit of a bend in it.

Upper ball joint also bent.

So our parts list is growing. I now need to get a new rotor, new hub, new upper and lower ball joints and maybe a new lower A-arm. Before I start wrapping the work up and re-join the Christmas festivities, I happen to take a look at the upper A-arm. We can add that to our new parts list too. The upper A-arm showed previous damage that was repaired. Where the repair was welded, another crack had manifested itself just outside of the weld.

Crack on the Upper A-arm and a previous crash damage repair makes this part no good.

Finally, I pull the front right spring out of the spring bucket so that i know what the previous owner was running for a chassis setup. The front spring is an AFCO 800 pound spring. Seems a little stiff for my taste, but we need to document what came out of the car to give us a point of reference.

Front Right spring is an AFCO 800 pound spring.

Quickly but quietly, I put the tools away, store the parts in a plastic tub, and go back inside to see if Santa left a couple ball joints in my stocking.


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