|
|
FRPP Disc Brake Conversion Kit Upgrade - Project ProCharged Pony - Throw Out The AnchorWhile ABS may be out of our reach, strong stopping power isn't, with help from Ford Racing Performance Parts. From the May, 2003 issue of Muscle Mustangs & Fast Fords By Steve Baur Photography by Rick Jensen
|
|
Slipping and sliding is now... Slipping and sliding is now a thing of the past. And we look good, too, thanks to Ford Racing Performance Parts and Discount Tire. Let's face it, Fox-body 5L Mustangs have never been known for their stopping prowess. Ten and a half inch rotors up front and 9-inch drums out back just don't cut it in today's world of anti-lock, four-wheel disc braking. And if you have brought your pony to ultra-modern power levels, like we have, you're not only under the gun, you're under the firing squad! Since supercharging our '90 GT with ProCharger's P-1SC huffer, our horse gained 130-plus rear-wheel horsepower and is hauling its tail like never before. Stopping the pony was a problem prior to the power enhancement, and so we looked to Ford Racing to provide a remedy. In the heart of the Ford Racing Performance Parts (FRPP) catalog, one will find the five-Lug Front/Rear Super Heavy-Duty Cobra Disc Brake Conversion Kit, otherwise known as PNM-2300-K. We went to FRPP for improved braking mainly because it uses all factory equipment. If we need to do a brake job, all we have to do is pay a visit to our local parts store for replacement rotors or pads. We also took into consideration the extensive testing these parts are subjected to before they go on a production vehicle. The kit is quite inclusive, providing everything you need to convert your failing Fox braking system into a stalwart stopper. Starting at the rear is a new set of 11.65-inch rotors and calipers, new axle shafts, brake lines and hoses. Four parking brake cables are supplied, as two are for '87-92 Mustangs, and the other two are for '93 models. Moving forward, giant 13-inch rotors and Cobra-embossed calipers really toss the anchor out when you step on the negative-G pedal, and new spindles with sealed-bearing hubs make changing rotors a snap. More brake hoses and lines are provided for the front brakes, and dust shields are supplied for all four corners. FRPP also includes a new master cylinder, brake booster, and an adjustable proportioning valve to ensure the four-wheel discs perform at their peak. We did mention the M-2300-K kit is a five-lug system. This requires a new set of wheels if you haven't already added the additional lug studs. Having the 13-inch rotors up front will also affect your wheel choice; with whatever wheel you choose needing the appropriate backspacing and clearance for the calipers. FRPP recommends a 17x8-inch wheel with a five-hole, 4.5-inch diameter mounting pattern, and 5.75-inch backspacing. This makes things very easy, as many of the factory Ford wheels already have this. Flipping through the FRPP catalog, we counted six different wheel styles that would work, and adding the '94-98 17x8-inch GT wheels would increase the number by two. So you have quite a few wheel choices without even going to the aftermarket, which has an immense number of custom wheels available with that backspacing. We had originally planned to go with some silver Bullitt-style wheels, but after talking with Dan Meadows at Discount Tire Direct, we opted for a set of Fittipaldi Force rims in a 17x8-inch size. The Fittipaldis are sold exclusively through Discount Tire and are available in 17x8-18x8.5-inch sizes. The Force rims featured a 35mm (5.85 inches) backspacing. Any more and we run the risk of contact with the front lower control arms. The wheels are machine cast and clearcoated for easy cleaning and a shiny finish, and once we checked them out on a Thunderbird in Discount Tire's gallery on its Web site, we knew they would give our pony a unique style and add a little pizzazz to the stock body.  As you can see, there are...  As you can see, there are a lot of parts to be installed. The good thing is they all fit perfectly because they are factory issue parts. Check out the big, juicy rotors. That's what we're talking about.  It's Christmas time at Eric's...  It's Christmas time at Eric's Performance! Here, Eric and Assistant Tech Editor John Hedenburg assess the various components. Hedenburg, our resident bracket racing maniac, assisted during the operation.  Eric began by dismantling...  Eric began by dismantling the rear drum brake components. This included removing the drums, springs, and shoes.  In order to remove the stock...  In order to remove the stock axles and backing plates, the C-clips and carrier pin need to be removed from the differential. Then the axles slid out.  Next, the brake lines were...  Next, the brake lines were disconnected and the backing plates were removed.  The kit comes with new backing...  The kit comes with new backing plates for the calipers. They bolt on using the stock mounting points, and are supported by moan brackets that bolt to the axle tube. The dust shields can then be installed along with the new, longer axle shafts. The axles are the same 28-spline units found in the '94-98 Mustang. Should your future include sidestepping the clutch with slicks, you may want to use a stronger axle, but for our application, these slightly thicker stock shafts will do fine. The wheel and tire package came in at $1,525, and Discount also supplied us with Gorilla chrome-plated lug nuts that use a special socket to install them. The design of the wheel necessitates the use of a slim lug, and you certainly don't want to use some horrid open lug on your hot new rims. The new brake hoses are attached... The new brake hoses are attached to brackets that are to be bolted to the shock support. To save time, we tack welded them to the support until we replace the shocks. Then we shall drill and bolt them to the bracket. The FRPP kit also includes two new steel brake lines. These are perfectly contoured to the axle. For rubber, Discount Tire recommended Nitto's NT555 radial tires. We opted for the '94-98 GT factory size of 245/45x17, but in hindsight, we may have been better off with a 235/45. The 245 increased the overall diameter of the wheel and tire, which not only changed our gear ratio, but also put the rubber closer to the fender lips than we would prefer. FRPP does say the kit may require the rear inner fender lips to be rolled, and bottoming out several times on the way home confirmed this (not that our pothole-infested New Jersey highways helped any). We also think the factory 139,000-mile rear shocks might be a little on the soft and worn out side complicating the matter. Going with the 235-size tire might lessen this problem a little, but if you plan to lower the car or have already done so, rolling the fenders will be a necessity. While the majority of the Cobra brake kit can be installed by the average enthusiast, there are a few modifications that require some special tools, which you may not have. Installation is pretty straightforward with the only real difficult parts being the installation of the new brake booster, cutting and flaring one brake line, welding the parking brake handle, and adjusting the proportioning valve. Testing and adjusting the proportioning valve may run into another day, but it is time well spent, as you don't want to have the brakes working incorrectly. Adjustment required a bit of wheel lock up to verify the back brakes lock after the front ones do. This should be done on a closed course of some sort, preferably on a low-traction surface like wet pavement. That will keep you from flat spotting the tires. The instructions with the valve give you a baseline to start with and it is fairly close. We made one full turn clockwise to increase the rear bias and after making a run, backed it off half a turn to find the sweet spot. The kit comes with some instructions. They are rather brief and the picture quality wasn't the best. However, Ford Racing told us the instructions for the kit are being completely revamped as this was being written, and all kits shall be equipped with them by the time you read this. They also recommend you have a '94-up Mustang service manual handy.  The new brake lines join at...  The new brake lines join at the differential with this new hose and connection. Simply remove the old one and bolt this in its place.  The caliper is attached by...  The caliper is attached by two bolts and holds the rotor on. The parking brake cables are installed next. There are four supplied cables. Two are for '87-92 Stangs, and the other two are for '93 models.  Here, Eric uses the supplied...  Here, Eric uses the supplied metal clips to fasten the parking brake cables to the floorboard. Not included in the kit are two metal springs that attach the parking cables to the lower control arms. Similar to carburetor return springs, they will prevent the cables from rubbing on the tires, and allow the necessary travel with the control arm.  Rear disc brakes completed....  Rear disc brakes completed. Stopping power eminent.  At the front of the car, the...  At the front of the car, the calipers and rotors are removed. Say goodbye to packing the bearings. The new units are sealed and support the wheel hub. The disc will fit onto that and be secured by the caliper.  To remove the old spindle,...  To remove the old spindle, support the control arm and then remove the two lower strut bolts, the tie rod end, and the lower ball joint. Here you can see the old spindle, the new spindle, and the wheel hub. If you're not familiar with braking systems, you might want to get a professional to install the system. This will ensure the components are installed properly and the system works like it should. Once the kit is installed though, performing brake maintenance is a snap. Two bolts hold each caliper on, and the rotors are held in place by the calipers. No messy bearing to repack and no springs and other assorted parts to come flying off of the brake drum. Work on our '90 Mustang GT was performed by Eric Ledbetter of Eric's Performance in Old Bridge, New Jersey. Eric has been working on cars, and Mustangs in particular, for years. He also owns a 9-second '67 Mustang, and an 11-second late-model notchback, so it's safe to say he knows his way around a Blue Oval. With a knowledgeable technician turning the wrenches, the complete kit can be installed in about 8-10 hours. The bulk of the installation can be found in the captions within the story. The new spindle is installed... The new spindle is installed with this spacer. Then replace the tie rod end and strut bolts. To verify the Ford components were worth the expense, we performed before and after brake testing at Old Bridge Township Raceway Park, New Jersey. Although closed for the winter (it was mid January when this was written), the track lets us use the open space to perform such tests. After complaining about the brakes in the opening paragraph, one should expect a monumental improvement in deceleration and we weren't disappointed. During our baseline runs, we managed to lock up the warped stock rotors a few times, as evident from the pictures. Once we found the right pedal modulation, we still went sailing past any acceptable distance. Using our Stalker ATS radar equipment to verify our braking data, we averaged 485 feet slowing from 100-0. With the Cobra four-wheel discs stopping us, that average was cut by 61 feet to 424. Just to give you an idea, 60 feet is about the length of four Mustangs. Further investigation of the chart will show you we gained stopping power in 70-0 and 60-0 tests, also. Add to that the ease of working on the disc brakes, and the kit's $1,795 price tag just bought you a whole lot of peace of mind. We have to add the new tires and wheels certainly had an affect on braking, also. The 245-size tires offer a bigger footprint than the 225-size rubber we had on the factory pony wheels. While both sets of tires were made by Nitto, the 225s were an all-season tread and not geared toward the same performance level of the NT555s. We couldn't be more pleased with the Ford Racing Cobra Disc Brake Conversion. The performance gain was absolutely fantastic and something that every Fox Mustang should be blessed with, even if it is still stock as a rock under the hood. The kit also gave us the opportunity to bolt on some awesome looking wheels from Discount Tire, giving it a well-deserved aesthetic upgrade. Fox Mustang owners, if you need improved braking, Ford Racing can give it to you.  The wheel hub slides on and...  The wheel hub slides on and then the caliper and rotor can be mounted. Before you do that, install the new brake hoses up front. That way you don't have those big honkin' 13-inch rotors in your way.  Like buying an answering machine,...  Like buying an answering machine, we're finally moving into the 21st Century. Here, the front brakes are finished with the exception of the dust shields. If you are using the brakes on a street application, definitely use them. The front pieces are installed using supplied pop rivets that require the Big Daddy (yes it's the actual name of the tool) of rivet guns.  Under the hood, Eric starts...  Under the hood, Eric starts by disconnecting the brake lines from the distribution block and the master cylinder, which is then removed from the brake booster.  The FRPP kit includes a new...  The FRPP kit includes a new master cylinder and brake booster to support the big discs. Four bolts under the dash secure the brake booster.  Here we compare the new and...  Here we compare the new and the old. The FRPP booster is quite a bit larger than the stock piece (it was designed for a different engine compartment) and requires a bit of muscle to get it into place.  To make it easier to install...  To make it easier to install the booster, we removed the driver's side engine mount bolt and pried the motor over.  The new distribution block...  The new distribution block is placed in the factory position and the bottom two lines and the top line mount as they did before. The driver's side brake line mounts in the back, but you will need to bend and cut it first.  Once you have the line bent...  Once you have the line bent and cut to size, you'll need to get a 7/16 tube nut and slide it on the line. Then use a flaring tool to, uh, flare the end of the line.  Installing the FRPP proportioning...  Installing the FRPP proportioning valve is a simple matter of disconnecting the joint over on the passenger's side and installing the valve between the lines.  The parking brake lever must...  The parking brake lever must be modified to prevent the rear calipers from hanging up. This is accomplished by cutting off the spring tab and welding the pawl to the handle with the second from the last tooth engaged.  Hedenburg bolts up the new...  Hedenburg bolts up the new Fittipaldi Force wheels. They measure 17x8 inches and wear Nitto NT555 245/45ZR rubber. Those with '87-90 Mustangs may want to consider getting the later model fenders if you want to run this size tire, as there is some occasional contact. If you don't want to change fenders, go with the 235/45 tires.  Hedenburg, a long-time bracket...  Hedenburg, a long-time bracket racer, shall be entering a new 5.0 class this year with expected elapsed times in the 7s-seven minutes that is.  No this is not a burnout shot...  No this is not a burnout shot (although our ProCharged pony is fully capable of it). This is the official front brake lock-up, "the photographer is gonna die" photo from our pre-Cobra brake test session. Associate Editor Rick Jensen narrowly escaped being scooped up by our ATI intercooler, and lived to photograph the car another day. You should have dodged left Rick.  The results are in. Brake...  The results are in. Brake testing is much like drag testing. You search for traction. The wider Nitto tires certainly helped, and having larger (and two additional) rotors reduced brake fade between runs. If we weren't conducting these tests in the dead of winter, all of the measurements might have improved, but there was nothing we could do about the mid-20 degree temperatures. We were still able to drive away with great results.  A final look at our new Ford...  A final look at our new Ford Racing Performance Parts Cobra brake kit and Fittipaldi rims from Discount Tire. You really can't go wrong with stock pony wheels, but the Fittipaldi Force pieces really wake up the Mustang in the looks department.
|
|
|