Do you ever really consider everything there is to factor in when you lower a car and/or add adjustable suspension? There may be a lot more involved than you first imagined.
Take, for instance, upgrading to rear disc brakes on an Impala. Under normal factory conditions, it’s literally a bolt-on deal; but when the suspension’s been altered (lowered) and/or the rearend housing’s been narrowed (not to mention one of Ford 9-inch nature), which is often the case, you’ve got some variables to work “around.” Namely, you’ll experience interference between the caliper and the frame — mostly the E-brake mechanism, as well as portions of the caliper body itself. If you’re not willing to address the framerail accordingly (by notching it), there is a solution.
Classic Performance Products (CPP) offers a variety of rear disc brake kits, including ones specifically suited for such “non-stock” applications. Their 9-inch Ford kit can be ordered without emergency brake option, which basically translates to using front calipers on the rear. Furthermore, they provide the necessary frame clearance without having to necessitate the E-brake cable hookup, the calipers can be mounted in a more downward position, ultimately giving you the room for full (adjustable) suspension travel.
With its Currie Enterprises-supplied Explorer disc brakes already coming in contact with the frame with our ’68 Impala on “fixed” suspension (RideTech coilovers), in order to further facilitate the pending airbag setup, we sent the car over to CPP to have the situation resolved with their slotted/vented rotor, S-10 caliper kit installed.
Bedding New Brakes
Unlike with drum brakes, after installing new disc brake pads/rotors, you need to bed (break in) the pads; adding a layer of friction material to the rotors improves braking performance, provides smoother operation, and helps eliminate squealing. Find a safe stretch of unpopulated road (or larger empty parking lot). Bring the brake rotors up to temperature by performing a series of progressively faster stops — 45mph, 55mph, and 65mph — applying more pedal pressure as the speeds increase (without coming to a complete stop). Once you start smelling the brakes and begin noticing them fading, they’ve reached temp. Allow them to cool by continuing to drive vehicle at low speed with minimal brake use for the next 20 minutes. Typically, break-in occurs after first session; follow-ups may be required for more aggressive type friction material and rotor surfaces.
1. Classic Performance Products’ 9-inch Ford rear disc brake kit (CP2105-38-5434NE) includes everything shown: 11-inch slotted/vented, cross-drilled rotors, S-10 metric caliper, brackets, braided stainless flex hose, and all required hardware/spacers.
2. With the old Ford Explorer OE disc brake setup long gone, CPP mocked up a “standard” 9-inch disc brake conversion kit — both the 5/16-inch mounting bracket and E-brake lever cause interference problems, even in normal fixed-suspension travel. No bueno, especially consider the airbag system that will be installed.
3-4. The solution, as mentioned, is to use CPP’s non-emergency brake kit — with the calipers clocked in a lower position, requiring the mounting brackets to be swapped and flipped upside down.
5-6. CPP recently developed a 9-inch Ford axle shim kit to help avoid (or in this case, remedy) bent axle flange brackets caused by tightening onto larger bearing seals. When setting up the caliper brackets, select the appropriate number of shims to take up the gap between bracket and axle housing.
7. With the shims sorted out, secure the caliper bracket by tightening down the 3/8-inch T-bolts. Make sure lock washers are used.
8. The bracket that hangs the caliper itself will also require some precise fitting. Supplied is an assortment of spacer blocks to accurately locate the caliper over the rotor; start by using all eight (four top, four bottom) to see where that puts the caliper.
9. As you can see, maxed out, our caliper is pushed too far in.
10-11. We removed two shims (one small, one medium), which put the caliper appropriately centered over the rotor. Securely tighten down the bracket bolts once the fitment has been handled.
12. With the caliper bolted in place, depending on your particular shock/trailing arm mount situation, you may or may not experience some additional clearance issues with the casting around the brake line port.
13. If that is the case such as with ours, simply (and carefully) remove excess material from the caliper, which will allow the banjo to be installed pointing the brake line out and away from the rearend bracket. (Be extra cautious and seal the fitting port so as not to get any debris inside!)
14. With the last of the fitment issues out of the way, secure the caliper in place for the last time.
15. Here you can see that without the extra clearance, the banjo would have routed the flex line directly into the trailing arm bracket. With the caliper clocked in this position, rearward is the only feasible way to direct the hose.
16. Also included in CPP rear disc kit are convenient rearend housing clamps and to mount the pre-bent flex-to-hardline tabs.
17. And with that, CPP’s modified install is complete. Next up, their narrowed-hub front disc brake kit.
18. And as a rule of thumb, despite pointing it out at the “end” of the story — always make sure your wheels clear any new brake/suspension components “before” you install the parts! And once you’ve put a few miles on the car, and properly bedded the brakes (see sidebar), re-torque your lug nuts to spec.
A Tip About the Tip
This “Paint Tip of the Month” issue is once again brought to you by the painting specialists from Axalta Coating Systems. This basic advise should help all lowrider painting enthusiasts, whether you paint in a high-collision repair shop or your garage out in the back! This simple advice is about the right tip size you should be using for your spray gun. That’s right; whether you are using a high-build primer sealer, clear, basecoat candy, metallics, or solids, using the right tip size is what gets the job done right from the start. This is something of a problem, Steve, our paint specialist, runs across quite often being a tech rep for Axalta Coatings Systems. When he gets called into a shop to help troubleshoot a problem, he finds out from time to time that painters are not using the right tip size for the materials they’re working or spraying. For instance, if your priming a car with a high-build primer you should be using a tip size of 1.8 to 2.1. This is your window for the primer to achieve the right film build. Also, all too often painters like to recycle old base and sealer spraying guns, thinking they will work for primer, but that is just not the case. This is why it is so important when you purchase any Axalta Products from local distributors that you ask for the technical data sheets with the product you are purchasing. This will give you the total breakdown in detail of the right tip size you should be using for the product that you are purchasing. If you need any further assistance in automotive technical painting advice please feel free to contact Steven Chaparro at firstname.lastname@example.org