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1967 Chevrolet El Camino Suspension Upgrade - Rehab ProgramNew suspension and brakes turn this ’67 El Camino from zero to hero. From the June, 2012 issue of Chevy High Performance By Steven Rupp
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The great thing about buying a beat-down classic A-body is that you don’t need to hock household items or sell off family members to medical science to afford one. The bad thing is that it has a low buy-in for a reason. Lots of wear, lots of tear, but then again making treasure out of trash is what this hobby is all about. The suspension under this... The suspension under this ’67 suffered from a terminal case of being old and worn out. Over the years the springs had sagged to the point where spacers had to be added to keep the fenders off the front tires. A good example is Chris Gordziel’s ’67 El Camino. He picked up this hunk of classic Chevy iron for a measly $1,500. Of course, for that meager sum, it barely ran, had a few bashed-in panels, and was sketchy to drive on roads that weren’t laser straight. His first task was to get it running by dropping in a freshened-up big-block and fixing some of the body panels. With this complete, it was time to address the items that were conspiring to make driving the Elky a real buzzkill, namely the poor handling and brakes. Stuffed into the handling category are the steering components. After all, even a car with a top-shelf suspension package will suck to drive if it has vague, unresponsive steering. For handling we decided to go with Classic Performance Products’ (CPP) Stage II “Pro Touring” kit (PN 6467PTK2). Included are front and rear tubular control arms, front QA1 coilovers and rear shocks and drop springs, along with front and rear sway bars. Gordziel’s ’67 was rolling on tired four-wheel manual drums and he lived in constant fear of eating the bumper of the car in front of him. The solution to this was CPP’s Big Brake kit (PN 6467FRBKBB) that included rotors, calipers, hubs, spindles, parking brake cables, brake lines, brackets, and everything else needed to convert over to four-wheel disc. To finish off the upgrade we added in a 500 series steering box (PN CP50004) and a power brake booster kit (PN 6772CBB4), which included the proper disc/disc proportioning valve. Now a big pile of new parts is cool and all, but we wanted to see what the gain would be from dropping such a big stack of cash. We realized before starting this adventure that the stock 15-inch rims would never clear the new binders so we picked up a set of Vintage Wheel Works wheels and wrapped them in some street-friendly Nitto rubber. After all, we wanted to test the suspension/brake upgrades and the only way to do that fairly would be on the same tires. With all the parts on hand we grabbed our tools and headed over to Best of Show Coach Works in Escondido, California, for a little quality time on their lift.  Before the new parts could...  Before the new parts could go on the old junk had to come off. One area that gave us problems was the driver-side lower control arm bolt. To get it out we had to dent in the header a bit. (It’s OK, they were pretty ugly already.) If they were nice we would have needed to unbolt it from the head and lift it up a bit to clear.  They look sweet, but more...  They look sweet, but more importantly these new TIG-welded tubular control arms from Classic Performance Parts (CPP) are much stronger than what was originally placed on the ’67. The arms are made from 1.25-inch 0.120 wall DOM tubing and have thick 1.5-inch 0.188 wall pivot barrels. This ensures the pivots stay true even under stress. The arms come preassembled on new billet chromoly 4130 cross-shafts and pivot sleeves. These sleeves capture both sides of the bushing, unlike the stockers that are only retained on one side. As a result they’re much stronger and better resist flex. As a safety measure the control arms incorporate an interlocking shaft and sleeve design so that the bolts can’t work loose. The fact that they came with new ball joints already installed saved us the hassle.  CPP’s coilover system is based...  CPP’s coilover system is based around billet QA1 single adjustable shocks. Before going in the car we dabbed the shock threads with some antiseize and installed the ride height adjustment rings. With that done we installed the QA1 shock with its 10-inch 550-pound spring. The coilover shock assembly was bolted to the lower control arm, raised up and through the frame, and then secured with the supplied hardware.  With the new control arms...  With the new control arms installed the rest was easy enough for a caveman to do. The main reason for this is the front spindle, hub, steering arm, and brake parts came completely pre-assembled from CPP. The bearings were packed, brake pads installed, and all we had to do was place the assemblies between the control arms and lock them down with castles and cotters.  The twin-piston calipers will...  The twin-piston calipers will be a huge leap forward from the old drum brakes and the zinc washed, drilled, and slotted rotors should work as good as they look. The powdercoating and zinc cost a few bucks extra, but they ensure that the parts will stay looking great for a long time.  Here you can see the difference...  Here you can see the difference between the dainty solid stock sway bar and the 1.25-inch hollow CPP replacement bar. A bigger bar is the quickest way to tame body roll in any car and the big-block ’67 badly needed help in this area.  With the sway bar installed,...  With the sway bar installed, the front suspension was put into the done column. When the Elky was back on the ground we set the ride height using the coilover system.  Check out this vintage rear...  Check out this vintage rear suspension; it’s all original with the exception of the air shocks. The exhaust system was cut off in order to fit the larger rollers onto the car for the initial baseline testing. Chris Gordziel assures us that he’ll fix the line routing once the install is complete.  For the stock drums to come...  For the stock drums to come off the car, we had to pull the axles on the 12-bolt. To do this, we removed the pin-retaining bolt and dropped the pin. Just make sure that you don’t turn the axles at all with the pin out or else the gears will fall out of place. With the pin out, we removed the C-clips and carefully slid out the axles.  The upper triangulated control...  The upper triangulated control arms anchor in the rear to the 12-bolt housing. The rubber bushings are pressed into the housing and can be difficult to remove; we used a big hammer and an air chisel to get them out.  When compared to the stamped-steel...  When compared to the stamped-steel stocker, it’s pretty easy to see how much stronger the new upper arm is. The other huge benefit is that it’s adjustable, so we can dial in the pinion angle and better align the rearend.  We lubed up the new bushing...  We lubed up the new bushing and tapped it into the housing until it bottomed out. We then installed the new upper control arm. To make sure we were in the ballpark, we set the length the same as the stocker that was removed.  Before the axles could go...  Before the axles could go back in we needed to install the new caliper bracket. Due to interference with the axletube suspension brackets, we had to reverse one of the T-bolts.  We then slid the axle back...  We then slid the axle back in place, installed the new 12-inch rotor, and attached the single-piston caliper. The caliper was aligned over the rotor using the supplied shims. Also, note the new longer wheel studs that came with the CPP kit. We just knocked out the stockers with a big hammer and used an impact to pull the new splined studs into place.  Like the upper the arm, the...  Like the upper the arm, the lower trailing arm is tons stronger than the stamped factory version and it has urethane bushings in lieu of the rubber version. The new tubular CCP arms also incorporate sway bar mounts.  The new QA1 shock bolted in...  The new QA1 shock bolted in place just like the old air shock did. The adjustment knob will make fine-tuning the shock a snap. With the shock in place we ran all the new brake lines CPP included in the kit and put the rear cover back on the 12-bolt with the gasket that was also included.  And here’s the new rear drop-height...  And here’s the new rear drop-height spring in place using the lower factory isolator. The top of the new spring differed from the stock spring, which meant we couldn’t reuse the original isolator. Our solution was to wrap the big end of the spring with a small section of hose.  Like the front, the QA1 shock...  Like the front, the QA1 shock offers simultaneous compression and rebound adjustments with the 12-position knob. They feature QA1’s deflective disc valving and are 100 percent dyno tested.  Having a rear sway bar should...  Having a rear sway bar should really pay off in the handling department. The new 1-inch solid bar is huge step up considering our Elky didn’t have one to begin with. The completed rear suspension sure looked better, but the real question was how much better would it help our Chevy handle.  With the main work done under...  With the main work done under the car, we turned our attention to what needed to be done underhood. In addition to drums, our El Camino also had manual brakes—not a great combination at all. The stock master was ditched, and in its place we installed an 11-inch power brake booster and master cylinder combination. Like the front spindles this came fully assembled from CPP and included all the brake lines to plumb in the proper proportioning valve. The larger booster was a tight fit but it cleared the big-block valve covers, inner fender, and windshield wiper motor. Sure, the new parts looked great, but what we wanted to know was how much better the ’67 would perform. To keep this a suspension test and not a tire test we made sure to install our new 17-inch Vintage Wheel Works wheels and Nitto 555R tires prior to the baseline testing. This way we had a true before-and-after testing of the suspension and brakes. The big-block ’67 looked like it was getting ready to flip over onto its roof. It was fun to watch, but not conducive to good handling. Before getting motion sickness our wheelman, Nick Licata, was able to nail down a best time in our 420-foot slalom of 6.82 seconds, which equates to 42.1 mph and far better than we expected. On the other hand the four-wheel manual drum brakes were abysmal with a best 60-0 mph braking distance of 192.90 feet! That’s past the point of being bad and firmly into the dangerous category. With all the suspension parts installed, and the ’67 wearing a fresh coat of black primer, we headed back to our El Toro test track. After a few warm-up laps we were rewarded with a best slalom time of 6.22 seconds or 46.2 mph. This was a substantial improvement over the previous tests. Moreover the El Camino’s body roll was now under control and the tighter steering made the Chevy easier to weave through the cones.  We decided to replace the...  We decided to replace the stock steering box with a CPP 14:1 close-ratio 500 box. Having good steering response is critical if you want to improve the handling and feel of an older Chevy, and it’s one of the easiest upgrades you can do. The new CPP box turned out to be a direct replacement for the stocker. We also ordered new high and low pressure lines along with the correct rag joint to attach it to the steering column.  Our El Camino originally ran...  Our El Camino originally ran 15-inch wheels all around with its drum brakes. Unfortunately, those wheels were a no-go with the new bigger binders. Our solution was to pick up a set of wallet-friendly 17-inch Vintage Wheel Works V40 rollers and some Nitto NT555 tires (245/45/17 front and 275/40/17 rear). The wheels (17x8 front and 17x9.5 rear) are made from virgin 356 aluminum ingots and heat treated for strength. The tires have a 300 treadwear rating which means they will last as well as perform.  In the braking test we saw...  In the braking test we saw an even more impressive improvement with a 60-0 stopping distance of 120 feet. Knocking over 70 feet off the distance is huge, and—best of all—this performance was repeatable while the stock drums were toast after two panic stops. Five back-to-back distances revealed 129, 127, 123, 120, and 121 feet. We should also note that the ’67 didn’t pull to either side and nose dive was slight, even with the big-block weight up front.  Gordziel was happy to report...  Gordziel was happy to report that the El Camino is now a pleasure to drive on the street, handles great, and has a much-improved ride. He can also now hit the brakes without worry of plowing into the guy in front of him.
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