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SOME BASIC STUFF ABOUT THE BASIC PREDATORBefore we get into this stuff, lets set the racing rules with the following Rules, the PREDATOR dozen…
The PREDATOR Concept Stuff…
The predator is based upon experience gained over the past 25 odd years of racing, ovals, stock cars, formula cars road racing etc. Nothing in this car is novel, revolutionary or “one off”. Reluctantly, we can not so proudly state that we have “stolen” many of the design features from others….this is a compilation of features and designs which have proven themselves to be easy enough, strong enough and cost effective enough to be included in the Predator design. We anticipate that the basic concept of the Predator’s design will not change much over the years as there have been very few changes in Formula Indy cars since their inception in the early 70s. The metamorphosis of Formula Indy cars…some made good stuff and some from not-so-good stuff. Slowly, the class has gained an identity and its design separated from other similar classes such as Formula 440/500 road race cars, their closest relatives. Formula Indy Cars are often referred to as F/500 cars on steroids. Among the noticeable differences is the attention to finish and detail. Side pods, for example, on a road car are housings for radiators, coolers and usually finely detailed aluminum ductwork allowing for intake and exhaust of cooling air, clutch ventilation and usually houses the race battery and/or cranking battery (depending on the waistline of the driver). The pods always have a bottom and are made to exacting SCCA specs. Formula Indy cars on the other hand have taken a different direction, in that while the side pod also houses the radiators, it will also include a battery and perhaps a fuel cell likely all squeezed into the left side pod. Weight on the left is good…on the right is bad. Formula Indy cars rarely have “floors” in the side pods and it is easy to see that these are purpose built racers designed for short sprint racing which brings side pods into contact with one another from time to time. This ‘functional” theme is carried throughout the current design of cars which tend not to have fancy schmancy dash boards and interior cockpit finishes. When looking into a typical Formula Indy Car, you may see the ground along side the seat. A “no no” in road cars. The most noticeable difference is the presence of a roll cage. Road cars have approved hoops while oval cars need the protection of a cage. This is due to the fact that ovalcars deal with concrete walls around the perimeter of the track. This fact combined with the extreme close proximity to another car and the nature of open wheel racing, make the likelihood of getting up-side-down, a little more probable than possible. Road cars, on the other hand, enjoy fewer walls and have the benefits of gravel or “kitty litter” runoff areas. The Formula Indy car is the result of time testing with its current form following only its function. It’s appearance today is the result of Darwin’s theory of evolution wherein the strong survive, the weak don’t, although not natural selection, but evolution none the less. If you want to win, you emulate the winners. The kit concept… PREDATOR is designed as a race car which can be acquired in a series of kits, some of which are proprietary such as the body, chassis and certain suspension components of which most can be replicated. Brackets, tabs etc. are currently “burned” in a laser cutter which has created uniformity in parts. All of the bracketry and tabs can be made at home. This allows a racer to start the race project at a very affordable entry cost and continue as finances allow. It also allows a racer to exclude a portion of the car (a specific kit) when they have the wherewithal to build it themselves. Each kit is a compilation of the parts necessary and in lieu of the kit, a list of specs and parts can be obtained to allow the racer to build all the required parts of required. No plans are available for proprietary parts at this time. Assistance is always available. Turn key or complete race cars are not available from PREDATOR but, we can give information about those who can complete you kit for you at a fee. Now you can have a your turn key racer.
The following basic kits are available. · Basic Chassis kit· Basic Body kit· Front suspension kit· Rear suspension kit· Brake kit· Steering kit· Fuel kit· Cooling kitThe result is almost all the parts needed to construct your Formula Indy Carposit with the balance upon pickup. Current kit assembly fees are in the $800 to $1,500 range, depending on finish, plus required c oPREDATOR The Design stuff… The chassis is designed to be as safe, simple, strong, light and as inexpensive as possible. The space tube frame is available in two major configurations, a side engine model and the more traditional rear engine model. Other than the obvious engine location, the difference is the redistribution of weight to allow for maximum left side weight bias, extremely desirable in short oval racing. Both chassis can perform well and is a matter of personal preference. The chassis is completely triangulated and includes a either a dragster style roll cage or a style utilized in super modified racing. The dragster style cage features shorter lengths of tubing between weld joints which results in a stronger overall enclosure even though its overall volume is smaller. A side benefit of this compact cockpit package has been proven to reduce the “helmet to cage” distance. When properly padded, this reduced distances allows the helmet to incur the impact directly without the increased velocity attained when traveling a longer distance. The concept is why King Richard Petty ran close to the walls…”you don’t hit as hard when you are closer to it!” It is also more in keeping with the overall style. We call this ‘swoopy”,…a real technical term!
Metallurgy stuff… Okay, bring it on! This is a very sensitive area when talking with racers and race car builders. The basic argument is material…mild steel or chrome moly steel. Each has its benefits and its weak points. Because it is steel, both materials have an identical Modus of Elasticity, or deflection, when identically loaded. The specific characteristics of each come into scrutiny when bending them beyond their memory point. Mild steel has a limited memory. Its not as hard as moly and it will not tolerate as much bend as moly before it forgets its original shape. Bend a mild tube in the middle and it will eventually kink it and it will not spring back into its original shape. It takes the same energy to bend a mild steel rod to this point than it does chrome moly steel. Therefore, to attain the same degree of memory (confused with strength), mild steel has to be thicker than chrome moly tubing. The result is a package that is just as strong as mild steel but in a lighter package. That is the primary reason why the current crop of sprint cars and midgets are using fly weight tubing…to save weight! Today, the chrome moly chassis of midgets and sprint cars are literally the cheapest part of the race car and considered by the top runners to be disposable and are “swapped out” after a certain number of races. While weight is a real concern, we have addressed the memory/strength concept in a more pragmatic way. Given two pieces of tubing, one being a mild steel piece and the other a chrome moly piece of equal memory (mild steel being say .095 wall thickness and chrome moly being .065 wall thickness), lets examine the results of bending each. As we stated above, bending the mild steel beyond its memory first results in a bend that doesn’t’ return to its original position. By continuing the bend, we reach a point where the tube will kink. Once the kink begins, the tube loses a significant amount of structural integrity meaning it takes less energy to continue the bend than it did to start the bend. The mild steel can be bent around until the two ends are virtually parallel and the tube remains one piece. It retains SOME of its integrity throughout the bend and most importantly, remains in one piece. Further, the speed of the bend has little impact on the amount resistance encountered.When the chrome moly tube is bent as above, its characteristics vary. It offers as much residence to the initial bend due to the same Modus of Elasticity characteristics of all steel. However, it maintains its memory of original shape much longer than the mild steel did, i.e., we can bend the tube farther and it will go back to its original shape.By continuing the bend beyond its memory, we see a different characteristic emerge in the form of metal failure. Mild steel will kink and continue to deform. Chrome moly will deform slightly, kink slightly but then break into to two pieces. Therefore Chrome moly maintains its shape longer but loses all structural integrity when in two pieces. Further, the speed of bend has a major impact on its structural integrity. The slower the bend, the longer it maintains its memory before crack failure. The faster the bend (crash impact) the sooner the crack will occur. We have concluded that the only real benefit to chrome moly is weight savings and all basic Predator cars are made in DOM (drawn over mandrel) mild steel tubing. For the diehard chrome moly fans, you chassis can be special ordered in 5130 chrome moly. The weight savings is about 12% and the increase in price is about 250%. The Suspension stuff… One of the first things to jump out at you is the suspension system. While it may appear novel, it isn’t. CART, IRL and the whole F1 through F-whatever class of race cars have had this style, pushrod and bell crank, suspension system for the last two decades or so. Certainly, the idea of inboard suspension systems has been around for at least 30 years. We just haven’t seen them on short ovals for good reason. There are actually no other classes of Formula style cars which run on ovals except AIS, American Indy Car Series, which utilizes outdated (but still expensive) Indy/CART cars as its base of racers. The first comment from most folks is that it is costly, complicated and will add to the cost of the race car. All these criticisms are false, absolutely false and Predator has proved this from a functionality standpoint with the “COILON Ó” suspension system. Moving the suspension components up and to the center of the vehicle offers several advantages.
The front spindle is located outboard by straight lengths of mild steel tubing with weld-on ends. The fore/aft location is via two trailing arms also constructed with straight lengths of tubing machined or with “weld-on” ends. The result is a light weight, easy to repair and replace system which can be done at home or by any competent weld shop. There is no requirement for bending, jigs or fixtures. Weld-on ends and pre-made arms are available separately from different sources. Additionally, the arms can be made interchangeable from left side to right side meaning that only one set of replacements need be carried. The simplicity is carried into the aluminum pushrod with its inexpensive rod ends. If you need another and wish to make it, just whack off a length of tubing, drill both ends to the proper diameter and tap the ends for rod ends and you are done. Again, no jigs fixtures or welding. Only hand tools are required…carry several, they can interchangeable left to right depending on the chassis you choose. Premade, off-the-shelf “swedged” aluminum units can be acquired for even less cost and construction time. Bellcranks are simple also. The base units (as of December 20, 1999f) are laser cut from mild steel plate and stamped to form.. Wear bushings are from Sears Hardware. The pushrods activate the COILONÓ units. You can utilize any number of coil over shock absorbers such as, Penske, Koni, Carrerra, Pro, AFCO etc. and spend between $175.00 to over $600 per corner for these units…or you could consider using the basic COILONÓ unit we have designed and described as follows. The COILONÓ units consist of a Dodge Dakota Gabriel rear shock (gas bag type), a 3/8” rod end (which screws onto the pin end of the shock), the shock washers provided with the shock, spacer washers, one industrial die spring and two industrial die spring cups. The result is a compact inexpensive unit (a spring ON top of a coil) that rivals the big guys in performance and beats the heck out of all of them in terms of price. Industrial die springs are available from any number of industrial supply and mail order shops in rates from 70 to 700 pounds and can be mixed and matched to fine tune your racer…between $5 and $20 each. The only real drawback here is the lack of adjustable compression and rebound rates available in all-out racing shocks. For information about PREDATOR
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