RULES
These racing rules are still tentative, but they’re not likely to change much, if at all. They deal primarily with the car itself. Other rules covering race procedures, points, purses, membership, etc. will be addressed later.
This class is based on a “spec” car—i.e., one design, built by one company (Note i). The general rule is that the car cannot be modified, but any adjustment within provided adjustability is permissible. There are a few exceptions (e.g., max overall width, minimum weight with driver).
We Are Tyrese
Formula RPD Specifications and Rules
Specifications:
Formula RPD Specifications
Wheelbase (Note ii) ……………………………………………..80 in. to 83 in.
Overall Width (Note ii)……………….…………………………………………. 65 in.
Weight (less fuel) ……….………………………………………..approx. 950 lbs.
Overall Length…………………………………………………………...approx.144 in.
Overall height …………………………………………………………………approx. 45”
Things you CAN do
- use any shock (within a few limits) (Note iii)
- use any type or brand of spring, any spring rate, any type of helper spring or bump stop
- use any type or size anti-roll bar or means of adjustment use any ride height or wheel alignment setting (i.e., toe-in, toe-out, camber, caster, etc.)
- use droop limits
- raise or lower roll centers or use anti-dive or anti-squat geometry (within adjustability provided)
- use any weight distribution scheme (i.e., you can set weight “cross” or add ballast weight to change weight distribution)
- use any wing setting within adjustability range
- adjust tire pressures, modify tires by grooving, siping, shaving, etc.; use tire “stagger” (provided you achieve the stagger with specified tires)
- use tire pressure bleeders
-adjust brake balance (with standard brake bias adjusters or brake bias valves, or by changing master cylinder sizes)
- shut off one or both front brakes on dirt tracks
- use any brake pad compound
- change steering ratio (using pinions provided with the car)use any gear ratio (i.e., you can change both front and rear sprockets)
- Install mechanical in-car adjusters for any chassis function (i.e., brake bias, shock, anti-roll bar, cross weight, wing, etc.) Electric powered adjustments are permitted, but electronically controlled adjustments are prohibited (Note iv)
- convert to a paddle shifter system (Note iv)
Things you CANNOT do
- You cannot change wheel sizes or offsetsYou cannot exceed the maximum overall width (65”)
- You cannot increase or decrease the wheelbase (Note ii)
- You cannot use carbon fiber, titanium, magnesium, or any space-age material to reduce the basic weight of the car (the specifics and exceptions are detailed in section #7)
- You cannot modify the differential (Note v)
- You cannot modify the wings, add aerodynamic features, or modify the body or the underside of the car to gain aerodynamic advantage
- You cannot use anything other than the designated tires, and you cannot chemically alter the tires
Engines
The only engine specified for this class is the Kawasaki ZX14. The early ZX14 was 1352cc. displacement. Engines made after 2011 have a displacement of 1441 cc. (Cars using a pre-2012 engine will be allowed a weight advantage (see section #7 below).
The basic engine rule (Note vi) is that the engine (including the transmission) must remain completely stock, with the following exceptions:
- You can modify the cylinder head and anything that attaches to it (and no, that doesn’t include all the rest of the engine!) any way you want. That means you can change cams, valves, valve springs, ports, combustion chamber, etc.
- You can use any exhaust system design, any air intake system (i.e., air cleaner, air horns, etc.), and you can modify or replace the throttle bodies and/or fuel injectors. The only requirement is that you must use (i.e., start with) the stock head casting.
- You can modify the oil pan and pick-up any way you want. You can add a windage tray.
- You can use an aftermarket clutch
Electronics
- The car is supplied with an ECU made for Formula RPD by Performance Electronics, Ltd. The ECU can be accessed by an app that can be downloaded from Performance Electronics’ website. You can change anything except the max RPM.
- Engine RPM must be limited to a maximum 11,500 RPM.
- Data acquisition is allowed, so long as it doesn’t perform any active engine or chassis functions.
- Any form of electronic traction control or anti-lock braking is forbidden. (Note vii)
Radio Connections and Rear-View Mirrors:
- Two-way radio connections are allowed on road courses and on paved ovals.
- Two-way radio connections are not allowed on dirt tracks.
- One-way radio connections where officials can talk to drivers, but drivers cannot talk to officials, are always allowed wherever the racetrack mandates that requirement.
- Rear-view mirrors are mandatory on road courses.
- Rear-view mirrors are optional on paved ovals.
- Rear-view mirrors are not allowed on dirt tracks.
Fuel
- The only fuel allowed for this class is gasoline. (Note viii)
- Nitromethane, nitrous oxide, methanol, ethanol, or other power enhancing fuels and/or additives are not allowed.
Minimum Weight and Ballast Placement Requirements:
Minimum weight for car, less fuel and driver………….………………….940 lbs.
Minimum weight for car withdriver, but less fuel:
With 1441 c.c. engine (2012 or later) …………………...…………………….….….1125 lbs.
With 1352 c.c. engine (pre-2012).……………………………………………..….…….1050 lbs.
- Where it is necessary to add ballast weight to comply with minimum weight rules, the needed weight must be added in equal amounts to each side of the car on top of the radiator ducts.
- Heavy-duty ducts can be provided where it is necessary to add more than 15 lbs. per side. The heavy-duty ducts themselves add 6 lbs. per side.
- All ballast weights must be marked to show their weight and must be securely attached but easily removable (incase tech inspector wants to verify the weight).
- You can add weight to change the balance of the car if you think it will be advantageous. However, you are not allowed to replicate original components, using lighter materials such titanium, magnesium, carbon fiber, etc., and then add weight where it could be advantageous (e.g., adding lead under the seat) to bring the car back up to the 940 lb. minimum.
- If after a race a car-with-driver is under weight, coolant may be topped up, but if that is not enough to bring the weight up to the minimum, the car is illegal, and subject to disqualification.
Brakes
- Aftermarket brakes may be substituted for the brakes supplied with the car, but the rotors must be cast iron or steel. (Note ix)
- Front and rear brakes must have separate master cylinders, so a loss of pressure in one doesn’t result in total loss of brakes.
- All four wheels must have brakes, but one or both fronts may be shut off for dirt tracks.
- Brake proportioning valves are allowed.
- Driver accessible brake bias adjusters are allowed.
- Any brake pad compound may be used
Wings
- The wings are “spec”. You are not allowed to modify or relocate the actual wing in any way. Only the wings supplied with the car may be used. You are not allowed to add wings.
- You may modify the side plates (spill plates) but you can’t exceed 4 sq ft total area on any one side plate.
- You can adjust the angle of attack within the adjustable range.
Tires
Tires are a strictly “spec” item. Before the first race we will designate exactly what tires are legal for this class. We reserve the right to impose a rule limiting how many new tires a car may use per race. We don’t know yet whether we will do that, but that’s a possibility. We want to keep it simple and easy to enforce, but we don’t want to allow this class to turn into a money spending contest.
You are not allowed to chemically alter the tires (i.e., use tire softening chemicals).
You may modify dirt tires by grooving, siping, shaving, etc.
Safety
- Seat belts must meet SFI 16.5 or SFI 16.1, be within manufacturer expiration label (must have label). Seat belts must be installed and used in accordance with manufacturer’s instructions.
- All participating drivers must wear safety helmets that meet or exceeds the SA 2005 or SA 2010 Snell Foundation or SFI Foundation 31.1 Specifications and are labeled as such.
-All drivers must wear fire resistant underwear, socks, shoes, gloves, and a one-piece uniform fitted snugly around the neck, wrists, and ankles. It is recommended that you also wear a fire-resistant head sock and/or helmet skirt. It is also recommended that all above items meet SFI Foundation Specifications 3.2A and 3.3
- An SFI approved head and neck restraint system is highly recommended. An onboard fire system is highly recommended.
- Removable steering wheel incorporating a quick release mechanism conforming to SFI Specification 42.1 is mandatory.
- All cars must have high impact energy absorbing foam at least 1 in. thick behind, and alongside, of the driver’s head. It is recommended that padding alongside the driver’s head be of progressive density (hardness) to minimize the possibility of low-grade concussions due to the driver’s head continuously hitting the foam, particularly on rough dirt tracks.
- Padding on the roll cage bars is highly recommended. Roll Cage Padding conforming to SFI specification 45.1 is highly recommended.
Driver Eligibility
Formula RPD will issue a license to compete in Formula RPD events to any driver who, in the unanimous opinion of the designated officials, is competent to race in this racing class, and meets any other legal or insurance requirements. However, it should be noted that a unanimous opinion of the designated officials can deny a license, or revoke a license, whenever it is deemed to be in the best interests of Formula RPD and its members.
Certain conditions and exceptions may apply. (Note x)
Notes
Note i
This car is currently being built by Walt Boyd Racing, but in all probability, we will soon incorporate under a new name—Formula RPD, Inc., or Formula RPD, LLC, or something similar. For now, we will simply refer to the manufacturer as Formula RPD. In the first season of racing the only car available will be the car built by Formula RPD. We anticipate that at some point in the future other car builders may want to build cars for this class. Since Formula RPD owns all the rights to this class, it has the right to set the terms for licensing other builders. It is our intention to compile detailed design dimensions and specifications that will allow other builders to compete in the market based on factors such as price, safety, ease and cost of maintenance, etc., but will assure that there is no significant difference as far as on-track performance is concerned. Whether or not this will be possible, remains to be seen.
Note ii
The formula rpd car was designed with a nominal 81” wheelbase. However, the rear suspension arms are designed so that they can be turned over, moving the rear wheels back 1”, giving a nominal 82” wheelbase. We have not tested with the 82” wheelbase, but it is an available adjustment, and therefore legal. It may be advantageous under some circumstances. There is a 1” tolerance in either direction beyond the full nominal wheelbase range (i.e., anything from 80” to 83” is legal).
The car must roll freely through a frame that is 66 in. wide. (That gives about 1” tolerance beyond a normal set-up.) The tires can rub lightly, but it can’t be forced through, nor is it legal for the crew to lift the car so the wheels droop to get it through.
Officials may wave the maximum width limit in a post-race inspection if there is apparent damage from an on-track incident.
Note iii
Any conventional shock absorber (“shock”, damper) may be used, but
- Maximum of 4 shocks.
- Shocks must be independent from each other with no interconnectivity.
- Shocks must be either non-adjustable or manually adjustable (no electronic controls).
- G valves, inerters, and mass dampers are prohibited.
Note iv
Certain adjustments—e.g., an anti-roll bar adjuster—might require an electric motor, controlled by driver accessible switches, to be useable while racing. That would be acceptable; What we don’t want is any computer-controlled adjustments, or anything that could be wirelessly controlled from the pits.
We plan to develop some in-car adjusters that we will offer as accessories. We also plan to offer an accessory paddle shifter system. You are free to develop these things yourself, but you must be willing to sell them to us or to other RPD competitors at a reasonable price or allow us to copy them (if you patent them). We reserve the right to disallow anything that confers significant advantage at exorbitant cost.
Note v
The ATB (Automatic Torque Biasing) differential appears to be the best compromise for the three different types of venues that this class is designed to run on. For any one type of track, another type of differential or a “spool” (i.e., “locked rear”) might be better, but changing the differential from track to track would add a lot of change-over work, and, in the case of a locked rear on the ovals, would require rear tire “stagger” that typically adds costs. Quaife makes an ATB chain drive differential that is well suited to this application and is the make that is supplied with the car. You can’t modify it. Specifically, you can’t lock it. It must behave like a normal “open” differential when the rear wheels are jacked off the ground.
Note vi
The rationale behind this rule is keeping engine costs to a minimum by allowing only modifications that will (1) increase engine reliability and longevity, or (2) would be too difficult to enforce if forbidden.
In keeping with the basic rule, obviously you can’t increase the displacement. We have a simple way to detect a violation.
Note vii
Electronic traction control is detrimental to the sport; attempt to use it will, if detected, result in the car owner being suspended for at least a year.
Wiring harnesses can be zip-tied to the frame or other components but must not be taped to the frame or other components in such a way as to allow wires to be hidden (i.e., disappearing into frame tubes, etc.).
If traction control is suspected, the tech officials reserve the right to require the car owner to substitute an ECU supplied by the sanctioning body for the day’s activities.
Formula RPD, Inc. will endeavor to keep abreast of all techniques to detect traction control.
Note viii
Gasoline is the only fuel allowed. Pump gas is adequate with the stock compression ratio, but within the rules it is possible to raise the compression ratio to the point that race gas would probably be necessary, so race gas is allowed. It may become necessary to specify which race gasolines are legal.
Note ix
The reason for allowing alternate aftermarket brakes is that some car owners might be able to secure sponsorship by using a brand other than the one supplied with the car (Wilwood), and we see no reason to stand in the way of that. However, alternate brake calipers and/or rotors—including Wilwood components other than what is supplied with the car— must be submitted for approval. Rotor materials other than iron or steel—e.g., aluminum, titanium, ceramic, carbon, etc.—will not be allowed.
Note x
We have not yet written a formal “Release of Liability”, but all owners and drivers will be required to sign a statement holding Formula RPD, its employees, members, and anyone else associated with Formula RPD, harmless for any injury or loss resulting from any practice or racing related incident involving Formula RPD.
At this point we don’t what minimum age requirements may apply. We know there are some very young drivers who are very good and already have a lot of experience. We are looking into the issue.
