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1976 Chevrolet Camaro - A Sharper Knife -- Project g/28 Part 9Project g/28 turns with scalpel-like precision, thanks to Flaming River's new quick-ratio Steering box. From the January, 2009 issue of Popular Hot Rodding By Johnny Hunkins
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This is one of those stories where we scratch our collective heads and ask, "Why didn't we do this sooner?" And by "this," we mean swapping our old slow-ratio steering box for a new one from Flaming River. At the risk of sounding stupid, it's really important that a performance car--a g-Machine--turns willingly and predictably. And even though our previous test numbers didn't show it, our '76 Camaro turned pretty much the opposite of that. Our best 420-foot slalom speed of 46.2 mph looks great on paper (ironically, it's one of the quickest cars through this course we've ever tested), but the numbers don't express the difficulty encountered when steering Project g/28. Our steering problems aren't unique. Our 29-year-old Saginaw 800 steering box is a recirculating-ball worm and sector gearbox. As these wears out, the ball bearings that run between the worm gear and the steering nut wear down. That translates into steering slop, delayed steering response, and "hang-up" that occurs when the worn ball bearings try to climb over each other in the worm gear. Old musclecars almost always have sloppy steering, which is kind of a big deal, but we really plan on beating our car on the road course, so tight, crisp steering isn't a luxury for us, it's a necessity. The Choice Was Easy
All modern performance cars use rack-and-pinion steering from the factory because they're lighter, more responsive, and cheaper to manufacture. But, only two of these reasons, weight and responsiveness, are valid for retrofitting a rack-and-pinion into older cars. Some rack-and-pinion kits are indeed available for older musclecars, but not for Second-Generation F-bodies like ours--and they certainly aren't inexpensive or easy to install, even in kit form. At any rate, we're well aware of the tremendous fabrication headaches involved, and we didn't want the extra work. One reason we chose a new box from Flaming River is because of the ease of installation. It bolts right into the same place as the old box and allows you to use most of your existing steering hardware including the pitman arm, drag link, steering shaft, pump, and mounting bolts. A swap like this is within reach for most backyard mechanics, while a rack-and-pinion conversion is the sole domain of the professional or expert mechanic--but there's more to it than that. A less-considered problem for a rack-and-pinion swap is the safety issue. Older cars tend to have a much longer scrub radius, which is the line described between two points where the wheel centerline and the upper/lower ball joint centerline intersect the ground plane. The longer the scrub radius, the more leverage an object on the ground (i.e. a bump) has on the steering wheel. Late-model cars with rack-and pinion steering have front suspensions with a short scrub radius, so longitudinal wheel impacts have minimal effect on the steering wheel. Older cars (with steering boxes) have a longer scrub radius (the deep-dish wheel is the giveaway), but due to the construction of the steering box, the longitudinal impact on the tire is not easily converted into steering wheel torque. However, when older cars are converted to rack-and-pinion (without a corresponding reduction in scrub radius), the steering wheel torque resulting from a wheel impact can cause severe damage to the hands and thumbs. Since we're going road racing, this safety issue is a very real one. Flaming River offers steering boxes for Camaros in several ratios: 17:1, 16:1, 14:1, and 12:1. We chose the 14:1 (PN FR1561, $489) to replace our aging 20:1 stock box. We were on the fence with the 12:1 box (PN FR1560), but ultimately decided against it because of our high volume of highway driving. The 14:1 box would require fewer driver corrections at highway speed and still be a lot quicker than the stock box, so that got the nod. Virtually every message board on the Internet has figured out that the Flaming River box as a version of the Saginaw 800 box, so we'd look pretty dumb by implying it's anything else. A look at the unit followed by a peak under the hood of any of 5-million-or-so late-model GM trucks is a dead giveaway. We asked Flaming River about it, and the crew there could neither confirm nor deny it, so we'll just leave it at that. What we can say is that the FR1561 has instant turn-in, thanks to a rack-and-pinion-style spool valve that delivers more precise metering of fluid. What we didn't mention earlier is that the power-assist portion of a steering box is 90 percent of the box's personality--its "feel." With the rack-and-pinion spool valve, the Flaming River box has a tight, crisp feel with precise transient control. Overall, the feel is like a late-model Camaro or Mustang with a rack-and-pinion steering system. Simply put, this isn't something you're going to get from a vendor hawking rebuilt Saginaw 800 boxes. Price-wise, the Flaming River box is at the high end of the spectrum at $489. As a cost-conscious build up with a modest $20,000 budget, Project g/28 could've gone with a less-expensive box, but we thought the build quality and better feel of a brand-new Flaming River box was the way to go at the end of the day. The Flaming River box is also trivalent chromium plated for corrosion resistance, which will come in handy the day we go to spruce up the looks under the hood. Some readers will opt out of the Flaming River box to save fifty or a hundred bucks, that's a given, but if you really enjoy turning corners, this is the box for you. Installation
The FR1561 is a fairly straightforward installation, but there are some obstacles you'll want to be prepared for. For one, the input shaft of the FR1561 is suspiciously identical to a late-model GM truck with a Saginaw 800 box, which is to say it's completely different from a Second-Generation Camaro. The rag joint coupling of early Second-Gen Camaros is a larger diameter than the Flaming River's input shaft (which is 3/4-inch 30-spline). You can order up some nice universal joints and fabricate everything, but we prefer a stock-style rag joint that dampens engine and road vibrations. (As a bonus, this route is also easier and less expensive than universal joints.) Even though Flaming River is in the business of selling universal joints, we worked with them to develop a rag joint conversion (PN FR1951, $89.50) which requires you to cut the old rag joint off at the steering shaft and weld the new one in (the new piece has a steel pin that fits snuggly inside the hollow steering shaft). The new rag joint coupling fits the late-model input shaft perfectly and has a nice factory feel. The only other issue is the incompatibility of the old compression-style hose fittings with the late-model O-ring fittings. If your Camaro was built pre-'80, you'll have to convert your hoses over or use adapters. The low-pressure return-side hose isn't that big an issue, but the pressure-side hose will get your attention in a hurry if not done correctly. We found some fittings to convert the old compression fitting (on the factory line) to the O-ring fitting (on the box) at G&J Surplus Aircraft Supply in Ontario, California (909-986-6534). We scored it for $49 (including the low-pressure hose fittings), but can't say whether it's from a 747 or an F-14 Tomcat. For a little more you can buy Flaming River's hose conversion kit for F-bodies (PN FR1625, $175). It's a little more, but at least you won't have to scrounge around old jet engines to get the right parts. The kit has everything you'll need to finish the job, including new braided stainless hoses. To help us put it all together we called upon our friends at Don Lee Auto Service in Cucamonga, California. You'll remember from our last issue that Don Lee Auto Service helped us with our ring-and-pinion (Randy's Ring & Pinion) and Truetrac differential (Detroit Locker) installation and set up. Once again, technician Rick Galloway gave us a hand with the wrenches in exchange for a nice Mexican lunch. Working together, we finished the Flaming River steering box install and tackled a second task, a long-standing wheel fitment problem, in just a few hours. The Wheel Spacers
In the last issue of PHR, we also brought you the review of Nitto's new NT01 track tire, a high-grip DOT-legal competition tire that is setting new standards for performance and value. In the process, we spent a significant amount of time with g/28 on the 13-turn 1.45-mile road course at California Speedway in Fontana, California. As our first all-out track day with g/28, we discovered two problems that didn't show up in previous testing: the rear tires rub the inside of the wheelhouse under hard cornering, and the gas tank spills fuel from the vent tube under hard acceleration. This month, we were able to correct the first of those problems, the tire rubbing, thanks to some help from the wheel fitment experts at Motorsport Technology in Grand Terrace, California (909-514-0091). Earlier, we had tried small wheel spacers from Mr. Gasket with only limited success. The problem was that we were not getting enough clearance to fully eliminate rubbing. What we needed was an extra inch of clearance, which you can't really get from normal spacers since the studs are too short (not to mention it would be unsafe). Motorsport Technology builds billet aluminum spacers with wheel studs built-in. The spacer itself bolts to the axle using lug nuts that are nested in recessed openings. You then bolt your wheel to the spacer (it's now a solid part of the axle) using the studs in the spacer.We ordered a pair of 1-inch spacers built with a five-lug on 4.75-inch bolt circle. They cost us $160 (pair) and easily fit into our budget. (The alternative, a new rearend, would've been cost-prohibitive.) One nice side benefit is that the spacers now allow us to bolt up our company slicks, which are 26x10 Mickey Thompson ET Street DOT slicks mounted on 15x8-inch Centerline Telstar wheels. In the past, the wheels would not fit on g/28 because our larger Baer calipers interfered with the inside of the wheel. Now that the wheel is spaced out, there is plenty of clearance for the slicks. These wheels and slicks have been used on at least four other company project cars (some running deep into the 11s), so we look forward to bettering our 13.85/101 quarter-mile ET soon. One final installation note on the spacers: After bolting them on and trial-fitting the wheels, we felt uncomfortable about the clearance between the outside of the tire and the inside fender lip. There is a lot of metal rolled into the fenderwell by the factory, so we decided to whittle some of it away to provide an added margin of safety. With a carbide cutting wheel in hand, we trimmed the inside fender lip, leaving us with another 1/2-inch of clearance and no visible outward sign of surgery. dAfter mounting the wheels we noticed an immediate improvement to the stance. The rear wheels are now pushed out to the edge of the fender where they make an aggressive statement. The only down-side might be a slight loss of rear body roll and a slight increase in understeer, but we don't think it will be significant enough to negatively impact performance, in fact, it might even help. Still to Come
We're getting pretty close to the end of the line with our $20,000 budget, so phase one of Project g/28 will be wrapping up soon. We still need to get back to the track for some more quarter-mile drag testing, but before that we need to make a trip back to the chassis dyno for some serious tuning with a wide-band O2 sensor. With slicks, some 70-degree weather, and another 20 hp, we stand a fighting chance of getting into the 12s. As this is mid-August, we've got a few months before things cool down. In the meantime, we'll try to make the best use of our remaining dollars!  The Flaming River FR1561 steering...  The Flaming River FR1561 steering box has a 14:1 ratio (3.25 turns lock-to-lock) and costs $489. Thanks to a rack-and-pinion spool valve, steering is precise and responsive. Flaming River starts with a brand-new box, then upgrades it with a rack-and-pinion spool valve, trivalent chrome plating and a billet aluminum sector gear cover. Flaming River's reputation for building top-quality steering components is long standing, making our choice a no-brainer.  The Flaming River box on the...  The Flaming River box on the left features late-model O-ring fittings (18mm x 1.5 for the high-pressure feed side and 16mm x 1.5 for the low-pressure return side), which are not compatible with the early-style compression fittings on the original F-body box (right). From what we can tell, Camaros built through '79 had compression fittings. Later Camaros had the metric O-ring style fittings, making the Flaming River box a direct swap for them.  To connect the late-style...  To connect the late-style box to your early-style pump, you'll either need a new late-model pump and late-model lines, or this line kit from Flaming River (PN FR1625, $175). The kit includes braided stainless feed and return lines, adapters and fittings. The rag joint (upper right) is also recommended (PN FR1951, $89.50) and allows the late-style .75-inch 30-spline input shaft to work with your stock steering shaft.  Rather than go with the $175...  Rather than go with the $175 kit from Flaming River, we scrounged the supply-side high-pressure fitting (left) from G&S Surplus Aircraft Supply in Ontario, CA. G&S has thousands of obscure fittings for aircraft engines, and we scored everything here for $49. The low-pressure return side can use a standard AN elbow with an O-ring/AN adapter and barbed fitting (right) which can be spliced into the stock line.  We got started by removing...  We got started by removing the lines from the stock steering box using an 11/16-inch crow's foot line wrench. The high-pressure feed line has already been loosened and the low-pressure return line is being removed.  Down below, technician Rick...  Down below, technician Rick Galloway pulls off the old steering box. The pitman arm has already been disconnected using a splitting fork, the rag joint has been disconnected and the three 7/16-inch bolts holding the box to the frame have been removed.  Remove the pitman arm from...  Remove the pitman arm from the old box and put it on the new one. One thing to remember is that the pitman arm length controls the steering ratio, but don't be tempted to just install a longer arm--that will screw up the steering geometry. When installing the pitman arm on a new box, make sure to center the box. The FR1561 is 3.25 turns lock-to-lock, so we set ours at 1 5/8-inch turns from either end. Use a 1 5/16-inch impact socket to tighten the pitman arm into place.  Mounting the Flaming River...  Mounting the Flaming River box to the Camaro's frame is easy. It's just three 7/16-inch bolts. This is where you'll thank yourself for not converting to a rack-and-pinion. You'll be carving corners before the sun sets...  Next, it's time to remove...  Next, it's time to remove the steering shaft and cut off the old rag joint (on left). The Flaming River rag joint slips into the hollow column where you weld it into place. Before welding, you'll need to mock up the steering shaft in the car--wheels straight, pitman arm straight, and steering wheel straight. Mark how the joint is clocked and then tack it in place. You'll note that we drilled holes in the column and made a series of Rosette welds followed by a butt weld around the base. It ain't going nowhere.  Now fit the steering shaft...  Now fit the steering shaft with the new rag joint back into the column. (The shaft telescopes in and out as a safety feature in a head-on collision.) Tighten the 11/16-inch bolt on the D-joint after slipping the rag joint over the steering box input shaft, and then tighten the rag-joint bolt.  At the steering box, it's...  At the steering box, it's time to splice in the hoses to and from the pump. We used a tubing cutter to cut the high-pressure line where there was enough length left to accommodate the compression ferrule and collar. With the Flaming River line kit, you won't need to cut or splice the high-pressure line like we did.  Here are our surplus aircraft...  Here are our surplus aircraft fittings prior to tightening. You only get one chance to do it right, so make sure everything's straight and level. The elbow into the steering box has an O-ring adapter fitting on the high-pressure side (18mm x 1.5) and an AN fitting at the junction. An adapter in the center goes from AN (on the left) to a compression fitting (on the right). We got lucky finding this; you can't just walk into a Granger and find this stuff.  An AN 90-degree fitting with...  An AN 90-degree fitting with a barbed end and some low-pressure hose completes the low-pressure return line to the pump. If you want a power-steering cooler, this is the side to tap into (bottom hose). As we pointed out in the text, Flaming River offers a stainless braided line kit with everything you need to connect its box (PN FR1625, $175). We went the budget route and saved $126, and it all works well without leaking.  After tightening everything...  After tightening everything down, we poured a quart of Royal Purple Max EZ synthetic power-steering fluid into our stock pump. You'll need to crank the engine and cycle the steering wheel a few times to get fluid throughout the system. Check the level periodically and top off as needed.  At the rear, we pulled the...  At the rear, we pulled the wheels off and bolted on our Motorsport Technology spacers. Just bolt the spacer to your axle with standard lug nuts, then bolt your wheel to the spacer using the studs integrated into the spacer. We paid $160 for a pair of custom spacers--it sure beats buying a new rearend. We noticed no vibration at highway speed, which means they're perfectly concentric and balanced. Motorsport Technology can make any spacer thickness you want, and can even change bolt-circle patterns.  You can see what a 1-inch...  You can see what a 1-inch spacer does for the appearance in this before/after comparison. The tire isn't any wider, but it sure looks that way from behind...  ...The improvement in appearance...  ...The improvement in appearance aside, we no longer have to deal with the tire rubbing on the inner wheelhouse during hard cornering.  The final operation for the...  The final operation for the day was to eek out another 1/2-inch of clearance inside the wheelhouse. A carbide cutter was used to cut away some of the inside lip--about a 1/2-inch near the top. The steel is two sheets thick and diverges about halfway, so you can't cut it too close to the outside paint or else the layers will separate.  Before the Motorsport Technology...  Before the Motorsport Technology spacers we couldn't bolt our 15-inch slicks to g/28 because the calipers on the Baer Sport brake system interfered. The extra inch of space gives us the clearance we need to get our Mickey Thompson 26x10 ET Streets on--which was an unexpected surprise. With a little dyno tuning and waiting on some cooler weather, we might make it into the 12s and stay in our budget.
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