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1976 Chevrolet Camaro - Project g/28 Part 2PHR's new project car gets an affordable suspension that looks great, and really works-thanks to PST, Global West, Weld and Falken. From the January, 2009 issue of Popular Hot Rodding By Johnny Hunkins Photography by Johnny Hunkins
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Project g/28, our Gen II '76 Camaro, picks up momentum this month as we dive into arguably the most important system: the suspension. As the interface between the body and the road, the suspension can make or break the handling; get the suspension wrong and nothing else down the line matters. And while it is very easy to just throw a pile of cash and custom fabrication at a new project car, the real challenge is to get the good result without paying all that cash. As we stated in part 1, the goal of this project is to build a g-Machine without a lot of cash. Specifically, we'd like to get this thing done for under $20K-car included. It ain't gonna look pretty, but we think we can knock down some respectable numbers to the tune of 0.90g on the 200ft skidpad, 46 mph through the 420ft slalom, high 12-second quarter mile ETs, and a 60-0 mph stopping distance of 120 feet. In keeping with these goals, we selected a Gen II Camaro. These cars have much better suspension geometry than the highly sought-after Gen I cars, and they're cheaper too. Between 1970 and 1981, Chevrolet made over 1.9 million of them-and they all share the same suspension components. We haven't even counted the hundreds of thousands of Firebirds and Trans Ams built during the same period, but the sum of all Gen II Camaros and Firebirds makes it the most prolific musclecar ever. After finding our '76 Camaro for $2,300, we proceeded immediately to our Fontana test site-the parking lot of California Speedway-for some hard numbers. They weren't real great, but that's kind of the point: we ran the quarter mile in 17.63 seconds at 78.62 mph, the 420ft slalom was run at 40.3 mph, 60-0 braking took 216.9 feet, and the 200ft skidpad averaged 0.70g. This was with a completely stock car, right down to the Costco 205/70R14 whitewall tires. We knew Gen II Camaros had lots of potential, but unlocking that potential on a modest budget would require some thought. Right off the bat we knew we couldn't make any improvements to handling, braking or acceleration without a good foundation, and that means refurbishing the chassis. Translation: replace the ball joints, bushings, tie rods and the like. Performance Suspension Technology (PST) is known for their Gen II chassis and suspension parts, and they have a reputation for high quality and rational pricing, so they were our very first phone call. We ordered up PST's Super Front End kit, some polygraphite leaf spring pads, a quartet of KYB shocks, a drop spring kit, a G-Max front swaybar kit, and a body mount bushing kit.. This stuff totaled $1,276-just over half the price of our project car. Our second stop was for wheels. The goal was three-fold here: don't break the bank (i.e. no three-piece hoops), find something that will stand up to track punishment (i.e. no heavy Asian knock-off castings), and find a wheel that looks attractive and unique at the same time. We didn't want to have the same wheel that a ton of other cars have-but if others decide to copy us later on, that's cool. As a point of interest, the wheels "make" the car, and it's really disappointing to see how little thought other car owners seem to put into selecting a wheel. Of all the cosmetic things that can be done to a car, the wheels and the stance are by far the most influential on a car's look, even more so than paint color. After researching the options, it became obvious that when price was factored, we had to go with Weld's Pro Star XP. They are made in the sizes we need (18x8.5 and 18x9), they were relatively affordable (around $1,394 for the set of four), and they didn't look like every other wheel on the road. As a rolled forging, they beat the hell out of a cast wheel for strength too. But before we picked up the phone to order wheels, we did what most serious car builders would do: we enlisted the help of a professional artist-Kris Horton of Cars By Kris-to render our project with the wheels we were planning. This costs $300 to $400, depending on the project, and gives us an idea of what the finished car will look like, right down to graphics, spoilers, paint and stance. We like to think of it as a blueprint for how our car will look. It's also a great motivational tool to have a picture of the finished car pinned on your garage wall while the real thing is in pieces on the floor. With the Pro Start XP wheels mounted on the imaginary car, and our stance figured out, we had enough confidence to order the wheels. For rolling stock we went with Falken, a company that is rapidly gaining respect among hot rodders and g-Machiners. Falken tires have already won the respect of racers and performance enthusiasts in Japan, and as their product line gains visibility in the US, the same is happening here. What makes Falken different from many other overseas tire manufacturers is that the product line is tailored for the American market, i.e. the sizes are right for our big cars, and our punishing roads. Let's face it, most of the Asian tire manufacturers make plenty of tires for big-diameter rims and narrow footprints, but this stuff is all show and no go. We're not interested in bling, we want performance, and we want value. Those two criteria intersect with the Falken FK-451, our chosen tire. We say value because all four skins set us back just $684 through a well-known mail-order tire source. As an all-season tire, the FK-451 isn't going to get us all the way to our skidpad goal, but it will give us enough grip to evaluate our suspension mods for effectiveness. Once we get that dialed in, we'll step up to some R-compound tires when it's time to pull the real ammo off the shelf. Keep in mind, using an R-compound race tire from the beginning can only mask problems with the suspension and braking; we'll get as close as we can with the Falkens, using them to fine tune our set-up. As a matter of record, we bolted on the wheels and tires before doing anything to the suspension. This was to discover any possible problems with fitment beforehand, and we discovered plenty. Up front, we had initially chosen an 18x9 with a 6-inch back spacing. This proved to be too much, as we bent a wheel on the upper control arm upon making the first turn. Six inches is too much, so we dialed it back a bit, and ordered up some 18x8.5s with a 5.5-inch back spacing. This worked fine with the 255/35R18 Falkens, but our concern lingered. Under highway conditions the clearance was there, but what about hard cornering? When we discovered Global West's Gen II upper control arms had a slightly narrower profile than the stock upper control arms, we ordered a set for $535-bringing our total outlay to $6,189, including the car. Our last real hiccup with wheel/tire fitment was at the rear in the wheelhouse area. The 6-inch backspacing of the Pro Star XP is livable on a Gen II, but not ideal. The tire is so close to the inside that it rubs at the front of the wheelhouse; this is in an area that roughly corresponds to the cove where the rear seatbelt retractors reside. We got out a big mallet and hammered the offending area into submission, but later discovered on the skidpad that the tire would rub on the leaf spring when pushed hard. The quick fix turned out to be a set of quarter-inch thick wheel spacers (from Baer Racing) and some longer wheel studs. The clearance problem is now fixed, but we're a little dissatisfied with the appearance; we think the rear wheels are still too far sucked into the bodywork (compared to our artist rendering) and need to be pulled out to the fender lip. We're looking into some 1-inch thick bolt-on spacers which look promising. If they do the trick, we'll report back later. So what did we get for our $3,889 in parts? On the 420ft slalom course (six cone gates set 70 feet apart) we improved our speed from 40.3 mph (stock) to 46.2 mph. Of all our results, this was the real shocker because we TKO'd our lofty goal in the first round of mods-without a rear swaybar. As a point of comparison, the fastest car we've ever tested in the slalom ran 48 mph and cost well over $100K. Mission accomplished. In the 200ft skidpad, we went from a 0.70g average to a 0.79 average. That's right on par with most modern performance cars on production tires (i.e. Mustangs, Camaros, Firebirds). We feel a set of R-compound tires will push us over our 0.9g goal by a wide margin. For comparison sake, our '94 Camaro Z28 with Nitto R-compound tires and lowering springs (honestly, that's it!) has already run 0.94g thanks to R-compounds, so that goal is well within grasp. In the meantime we'll fine tune things to chip away as much as we can before using the DOT race tires. Who knows, maybe 1.0g is even a possibility. The skidpad, however, did bring into focus a concern we had early on. These cars have room for a lot more tire than earlier Camaros and Firebirds ('67-'69). This is something that should be taken advantage of if at all possible. The controlling factor here was not finding trick suspension parts or doing months of fabrication (like with first gen cars), but of finding a wheel wide enough for the space available. The fact is, the only way to get a big enough wheel into these cars is with a custom three-piece hoop. That would double the price of the wheels for another 0.02 or 0.03g in lateral road holding. Is it worth it? The looks alone would tempt us, but when it comes to dollars and sense, an R-compound tire will get us to our skidpad goal with cash to spare. Of course, if Weld can build an 18x9 with a 5.5-inch backspacing (or even an 18x9.5!) we could fit a 275 tire up front. An 18x10.5 with a 6-inch back spacing would be perfect for the rear and could fit a 315 tire, but we're just day dreaming out loud. The final test we ran was 60-0 mph braking. Even though we didn't upgrade the crappy front discs and rear drums, we calculated that the larger footprint by itself would be enough to effect an improvement in braking. What we found was the biggest improvement (by percent) of all the parameters we measured. Stopping distance went from 216.9 feet to just 163.9 feet-an improvement of 24 percent. Sure, 163.9 feet is nothing to write home about, but at least we no longer have to put our foot out the door to stop the car. Our next stop is Baer Racing in Phoenix, Arizona. We're going to upgrade the rear drum brakes to a Sport system (11.35-inch rotor with 1-piston PBR caliper, $875), and the front discs will be endowed with a GT system (12.75-inch vented rotors with 2-piston calipers, $1,345). We'll also add a proportioning valve ($55) to adjust the rear brake bias. The whole deal will set us back $2,275, which is a few hundred less than we budgeted for. Can we get our braking distance down to 120 feet? Check out the June issue of PHR to find out!  When we last left you, we...  When we last left you, we were about to install a new set of tires and wheels on Project g/28, our '76 Camaro project car. We ordered 18-inch Pro Star XP rims from Weld and drove over to Falken Tire in Rancho Cucamonga, California, for the install.  The problem with building...  The problem with building a (relatively) low-cost g-machine while gaining performance and creating some kind of unique identity is picking the right wheel. The Weld Pro Star XP turned out to be both affordable (around $350 a piece) and great looking. It's also nice to look different from the crowd. We initially chose 17x9s front and rear, but had to drop back to 8.5s in the front due to clearance issues.  The Falken FK-451 isn't billed...  The Falken FK-451 isn't billed as an ultimate street tire, but we found it to be a competent performer in all our testing. When the dust settled, the FK-451 was within 0.01g of the much more expensive BFG g-Force KD (as tested on a more radically-built '69 Camaro). The larger 275/40R18s on the rear visually complement the smaller 255/35R18s on the front, but does the combo work as good as it looks? Read on...  A trial fitment of the Falken...  A trial fitment of the Falken 275/40R18s showed some initial rubbing on the inner wheelhouse. The 6-inch backspacing on our 9-inch wide Weld wheel was the culprit, but this was the minimum backspacing Weld makes in this line. We spoke with Weld about this, citing the 1.9 million Gen II Camaros built between 1970 and 1981, and told them we'd like to see less backspacing in this design, but no word yet on new part numbers. Until then, we can make these work.  To solve the problem of tire...  To solve the problem of tire interference, we took a multi-directional inertial device (okay, a sledge hammer) and arranged for it to meet Mr. Wheelhouse. This isn't something we recommend for everyone, but our '76 is a jalopy, so it's cool. It didn't need much persuasion, just some strategic clearancing in one area.  Up front, our 9-inch wide...  Up front, our 9-inch wide wheel (with a 6-inch backspacing) proved to be too much, as we destroyed one rim while making our first turn. The inside lip of the rim rubs the upper control arm, so we ordered 8.5-inch wide rims with a 5.5-inch backspacing. This solved the problem-but not without some carnage. Don't you just love it when a magazine ruins stuff in the name of science?  This close-up shows how nicely...  This close-up shows how nicely stamped steel grinds into soft aluminum. The wheel was so deformed after contacting the control arm that it could not be computer balanced. If we could convince Weld to build a 9- or 9.5-inch rim with a 5.5-inch backspacing, that would be a perfect "10" on a scale of 1 to 10.  Back at the Primedia Tech...  Back at the Primedia Tech Center, technician Jason Scudellari prepares to install our PST suspension and Global West upper control arms. Here, you can see the de-arched leaf springs, lowering front springs, tie rod ends, ball joints, bushings, and swaybars. Since our '76 was not originally equipped with a rear swaybar, we left this out of the installation. As a side note, we did eventually try a rear swaybar on Project g/28 (for a story in sister magazine Super Chevy), and our cornering deteriorated significantly.  We're not going to make this...  We're not going to make this a blow-by-blow install story, but there are some points we'd like to make along the way. Item one: there's nothing wrong with retaining the stock lower control arm on a Gen II Camaro. The geometry is already very good, so a change to firmer polyurethane bushings and new ball joints will get you within 95 percent of what a completely new fabricated tubular unit will do on the track. We can't say enough about how much difference the PST control arm bushings made.  The decision to go with the...  The decision to go with the Global West upper control arms wasn't made lightly. At $535 a pair, they aren't exactly cheap, and we had a budget to stay on, but after our wheel-mangling incident we felt we needed a control arm with a narrower profile and some added stiffness. We held off on the better Del-A-Lum bushings to keep cost down. Del-A-Lums would take the bind out of the suspension motion (relative to a polyurethane or rubber bushing).  The PST steering end links...  The PST steering end links really made a difference, both in terms of our own peace of mind, and their performance. A '76 model car doesn't sound old compared to some of the cars we cover, but this is 29-year-old stuff, and we just weren't comfortable with placing our lives on the line to save a few bucks. We want to beat the crap out of this thing on the track, and that means making it reliable as a rock.  This shot illustrates the...  This shot illustrates the difference in thickness between the stock swaybar (1.0-inch diameter) and the PST G-Max swaybar (1.125-inch diameter). There are two schools of thought regarding swaybars (also called anti-roll bars): control roll stiffness with swaybars and go relatively light on spring rates and dampers, or go light on the swaybar diameter, and control roll stiffness with springs and dampers. We opted for the latter, and as you shall see, we were rewarded on the skidpad and slalom course.
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