Project 10 The Hard Way – Rear axles and brakes to fill the 9″ Ford housing
Rear axles and brakes to fill the 9" Ford housing
It has been a very busy couple months and I am disappointed I had to miss a couple updates on the "Project 10" Firebird. I am going to try to get caught up a bit by getting a few tech stories out in the next couple weeks. This article is about the decision on brakes and axles for the S&W-built 9" Ford bolt-in housing. I looked at three different brake set-ups and a couple different axle choices but I ended up thinking the Strange S/Series axles and brakes offered the engineering, reputation and prices that made them a good fit for the "Project 10 - The Hard Way" bracket car.
First up was measuring the rear-end housing and filling out the online Strange Axle Order Form. Pretty easy to do and the ends that S&W used were marked with a part number that indicted they are the small-GM ends. I sent the Order Form in and followed it up with a call to the tech line at Strange Engineering. They said it looked good and the axle kit would be sent in two days. I asked them about the S/Series line of rear brakes vs the Strange Pro Series rear disc brakes. His explanation made sense in that the S/Series has a more conventional rear rotor that is not vented and the caliper was similar in design, re-buildable but not polished. For a savings of about $150.00 for the rear brakes I not only liked the price but I knew I could stop the Firebird safely and do it for years.
In all the years I have been racing I have never put new rear axle bearings and the retainer ring on a new set of axles. Now for brakes; I have installed all sorts of aftermarket and OEM brakes. The point here is if you are starting on a new bracket car or rebuilding one don't worry about the little things. You can get good help locally if you look around or you can do it yourself with some basic tools. I have a 30 ton press at our shop, which I don't use much, but I figured it out and had the bearing pressed on in about 30 minutes. Any local machine shop or good automotive shop can do it for you.
I have rebuilt and installed the rear brakes on our dragster dozens of times so I was familiar with how they needed to be aligned on initial set up. Take your time, install the caliper mounting brackets and I like to put a little red Loctite on the nuts that retain the bracket. Make some spacers or stack up washers that fit over the axle studs so you can torque the lug nuts down on the rotors to make sure they are seated against the axle flange. Turn the axle with the rotor tightened down to make sure the rotor is flat and doesn't have a side to side wobble.
Now you can slide the S/Series caliper onto the caliper bracket (leave the brake pads off for this procedure). We are going to make sure the caliper is centered over the rotor so you will get equal pressure from both sides when brakes are applied and brake pad wear will be more consistent. Snug the bolts up but don't worry about getting them real tight yet. Once you have dome that get some feeler gauges out and see what the space is between the caliper and rotor on both sides. The first time I checked mine I had a .120" more clearance on the outside than I did the inside. When you move the caliper in you are moving out on the inside and in towards the rotor on the outside so you split the difference in the amount of movement you need to get centered. That means I needed to move it inboard about .060". The Strange S/Series rear brake hit came with several shims in different thicknesses. A micrometer or a caliper can save you some time by measuring exactly how think the shims are. I found two pair of shims that matched up at .058". I put them between the caliper and the bracket, slide the bolts in (this takes a bit of practice to keep the shims from falling out), measured the space on each side of the rotor and it was within a couple thousandths. I was very satisfied with that.
Now all you have to do is slide the brake pads in place and you have finished the installation except for one thing...brake lines.
I prefer to use pre-made flexible Teflon-lined stainless brake lines I can get from a local stock car parts house to run from the caliper to the metal brake line I mounted to the housing. That way if I need to remove the caliper for any reason I can sit it out of the way and not have to bleed the brake system again. I use another flexible stainless line from the body of the car to the housing so the rear suspension can move its full travel and not pull on the brake lines.
Run your brake lines from the master cylinder to the rear end along the frame connectors or under the edge of the rocker panel. Keep the brake lines out of the driveshaft tunnel so a broken driveshaft can't cut or smash your brake line.
I decided, for budgetary reason (otherwise known as a lack of funds) to keep the stock F-body factory disc brakes. I simply went to NAPA and bought new aftermarket rotors and new aftermarket calipers. I took the old-cracked rubber lines off and replaced with new aftermarket replacement hoses. I think I spent about $120.00 for all new front brake parts, repacked the front wheel bearings and out a new seal on each side.