Formula High School Rules 2013-14
All Formula High School vehicles are to be completed before all track events.
Absolutely NO fabrication will be allowed at the track events.
FHS officials reserve the right to disqualify a team if the officials believe there is a safety hazard present on the team’s vehicle.
Formula High School Classes
Formula Stock
Suspension: Solid front/rear axle only
Engine: Briggs & Stratton 16 HP Vanguard V-twin ONLY. To further clarify, we are accepting engines in the 3034xx and 305xx (horizontal) and the 3037xx and 3057xx (vertical) model line. Provided the engine is designated as a 30 cubic inch, OHV, "V-twin" engine that is rated at 16hp, and falls in the range listed above, it will be accepted. No other engine will be allowed. NO power adders or modifications to the engine allowed, except for wiring extensions, throttle and choke connections. Engine must have a throttle return spring attached directly to the throttle shaft arm. Removing or disconnecting the governor is allowed.
Fuel Pump: Stock Briggs vacuum fuel pump
Transmission: Centrifugal Clutch only
Max Rear Axle Speed at Engine Redline: 730 RPM
Max Overall Tire Diameter: 23”
Wheelbase: 81” – 87” measured from center of front spindle axle to center of rear axle.
Width: 54” to 60” measured to the outside edge of the mounted tire.
Ground Clearance: 2” MIN – 4” MAX
Formula Mod
Suspension: Solid axle or suspension
Engine: Any industrial engine manufacturer allowed, provided the engine be restricted to 16 HP (+/- 1 HP) and max displacement is 600cc. This may be achieved by installing an appropriate restrictor in the intake system. Motorcycle/ATV based engines are limited to 250cc.
Engine Redline: Open to match engine used
Fuel Pump: Electric or Vacuum, Electric fuel pumps may be used, provided power is cut to the pump when the battery switch is turned to the OFF position or an alternative safety measure is used.
Transmission: Centrifugal Clutch/CVT/Multi-gear: Transmission MUST utilize some type of clutching mechanism to allow the engine to idle.
Max Rear Axle Speed at Engine Redline: 730 RPM
Max Overall Tire Diameter: 23”
Wheelbase: 81” – 87” measured from center of front spindle axle to center of rear axle.
Width: 54” to 60” measured to the outside edge of the mounted tire.
Ground Clearance: 2” MIN – 4” MAX
Formula Prototype
Body: Teams must use a full fendered body-shell design. Teams are encouraged to use the prototype body shell
Suspension: Independent front suspension with independent rear or multi-link rear suspension.
Engine: Any engine manufacturer allowed, provided the engine originate from a 20-23 HP base industrial engine or limited to a max 250cc motorcycle/ATV engine. 30 HP MAX after modifications to the engine. Teams must install the appropriate intake restrictor for their engine.. It is highly recommended that teams document engine power with dynometer results.
Engine Redline: Open to match engine used
Fuel Pump: Electric or Vacuum, Electric fuel pumps may be used, provided power is cut to the pump when the battery switch is turned to the OFF position or an alternative safety measure is used.
Transmission: Centrifugal Clutch/CVT/Multi-gear – transmission MUST utilize some type of clutching mechanism to allow the engine to idle.
Max Rear Axle Speed at Engine Redline: 810 RPM
Max Overall Tire Diameter: 21”
Wheelbase: 80” – 81”, Must fit roadster body-shell wheel openings
Width: 68” to 72” measured to the outside edge of the mounted tire.
Ground Clearance: 2” MIN – 4” MAX
Vehicles not within these measurements will not be allowed to compete, even as an exhibition. Vehicle widths and wheelbases are set to ensure a safe and stable vehicle for track day events. Specifications must be followed. There will be no exceptions.
Chassis: All teams must use the supplied chassis model as the base for their vehicle. Chassis MUST be constructed to the chassis model within 1” of specifications. All frame members shown on the model must be present in the completed chassis.
Prototype design may be allowed to modify the original drawing, provided the chassis retains appropriate margins of safety.
Roll Bar Tubing: 1 ½” round mild steel tubing, 0.083” (14ga) wall thickness. Roll bar tubing must be a single continuous piece. NO SPLICING ALLOWED. Driver’s helmet should not be excessively forward of the roll bar protection when seated in the vehicle.
Prototype design may be allowed to modify the original drawing, provided the chassis retains appropriate margins of safety.
Bracing: 1” round or square mild steel tubing, 0.083” (14ga) wall thickness.
Floor: 0.0747” (14ga) mild steel sheet, stitch welded to the bottom frame rails. The minimum weld stitch pitch should be no more than 1-3.
Prototype floor may be allowed to use alternative flooring techniques, provided the floor retains appropriate margins of safety.
Body Shell: Teams must use an approved FHS fiberglass body shell. If a team chooses to use an alternate body shell, that team must submit approval directly to FHS officials. The only approved body shell materials are: fiberglass, Kevlar, carbon fiber or 0.032” aluminum sheet. Aluminum must either be polished or painted.
Appearance: All FHS vehicles must be painted, gel coated, or powder coated with school and sponsor decals appropriately placed. Bare metal frames will not be allowed.
Mandatory Decal List (List may change at later date):
- Sugar Grove Custom Cars
- Fiberglass Solutions
- Road America
- Briggs & Stratton
Decals must be placed in a position where they are easily seen from both sides of the car. FHS officials reserve the right to add to the mandatory decal list at any time.
Firewall: .032” or thicker aluminum or mild steel sheet must be used for a firewall between the driver and the engine compartment. The firewall must extend all the way to the body shell. Teams must try to make all reasonable efforts to fully seal the driver’s compartment from the engine compartment. Teams should try to keep all gaps to less than ½”.
Safety Harness: All teams must use a 5-point safety harness, installed to safety harness manufacturer’s specifications. Harnesses certification stickers must be within five years of event date. If harness is passing through the firewall, clearance the firewall to eliminate possible harness damage.
Kill Switch: Two paddle type kill switches are required. One switch shall be located in easy reach of the driver’s right hand and labeled appropriately. The second switch shall be located on the left side of the rear roll bar but above the body shell. This location is shown on the chassis model. The switch will be marked with a red vinyl or painted 3” equilateral triangle and labeled ON/OFF with .25” high contrasting color text. Both switches must be demonstrated to effectively shut off the engine.
Fuel system: Teams may relocate the stock Briggs and Stratton vacuum fuel pump to allow proper fuel supply to the pump. Fuel tanks/cells must be commercially available, designed for fuel use and installed to manufacturers specifications. A fuel shut-off valve must be installed in the fuel supply line within 6” of the tank outlet. Driver operated fuel supply shutoff is highly recommended.
Exhaust: Exhaust outlet(s) must extend past the body shell by a minimum of 1”.
Tachometer: To help speed up official inspections and to verify engine speeds, teams are encouraged to install a tachometer in the cockpit. The Equus Tachometer (model 8068) has been proven to be very accurate and easy to install on a B&S Vanguard engine.
Tires: DOT or Racing slicks allowed.
In Event of Rain: Slicks will NOT be allowed to run if the track is too wet.
Minimum Size: No tires narrower than 175mm (example: 175/70-13 would meet minimum width, 165/70-13 would not)
Rims:
Stock/Modified: 13 x 6 OR 14 x 6 steel rim, 2.5” back spacing suggested
Roadster: 13 x 6 steel rim minimum, 13 x 8 steel preferred
Front Spindles: All teams must use standard or dropped VW Beetle spindles, ball joints, eccentric adjusters, rotors and disk brake calipers. No modifications allowed to these parts.
Prototypes may use alternative spindles, provided they follow proper engineering strength and manufacturing techniques.
Rear Brake:
Stock: All teams must utilize a standard VW Beetle brake caliper, actuating a single brake rotor keyed or splined to the rear axle. At least one rear tire must transmit braking power to the ground. This caliper will also be on a separate hydraulic circuit from the front brakes.
Unlimited/Prototypes: All four wheels must transmit braking to the ground. Two separate hydraulic circuits must be installed. This can be accomplished by a two separate master cylinders or a tandem master cylinder. Teams are not limited to the VW rotors/calipers.
Suspension:
- All teams must have a minimum of 1 successful year of Formula Stock experience before they may compete in Formula Unlimited/Prototype.
- Teams designing/building and IFS/IRS system must incorporate properly designed and constructed spindles, brakes and uprights.
- Teams must supply engineering drawings and or pictures of their design to FHS officials for approval before manufacturing their suspension.
Minimum Rear Axle Diameter: 1 ¼”
Steering: Rack and Pinion ONLY, no go-kart steering allowed.
Steering Wheel: Steering wheel must be either a continuous round or “D” shaped wheel. No butterfly style steering wheels allowed.
Minimum Tie Rod Diameter: ¾” steel tubing or 3/8" tap tubing (Coleman #16203) or equivalent
Driver Safety: All drivers must use the following safety equipment:
- DOT or Snell rated full-face helmet, manufactured within 5 years of event date
360 Plus Neck Collar (Pegasus Racing # 9308)- Closed toe shoes
- Long pants
- Long sleeve shirt/jacket
- Gloves
- Impact rated eye protection, minimum rating of Z87.
No sweats pants or windbreaker pants allowed.
Safety Glasses: All team members must be wearing safety glasses when actively participating in repair or adjustments to the team vehicle.
Overall Rule of Conduct: Students must present themselves in a professional manner. Teams will be disqualified and removed from the track in any team member does not follow directions from the officials.
SUGGESTIONS:
Rear axle bearings should be placed as close to the inner side of the wheel hub as possible to limit axle bending/twisting. Some teams have run up to a total of four bearings across the rear axle.
Chrome Moly Steel axles suggested. Low quality axles have bent under load.
Gear ratios: A good rule of thumb is to start with an overall gear ratio of 8:1 and then gear for the existing track conditions and individual vehicle response.
Chain tensioning devices: Use a sliding engine base set-up to adjust chain tension. There was a much higher incidence of thrown chains when using idler sprocket assemblies.
Install shaft collars on both sides of the rear hub assemblies. This is extra insurance to keep the hubs in place on the axle.
Fasteners: Teams should try to use at least grade 5 or higher fasteners, with nylock nuts, when possible.
Standard Formula High School wheel bolt pattern: 4 on 4”B.C., 2.5” back spacing.
Exhaust: Teams have run both open pipes and mufflers. The engines seem to work the best with some type of muffler. Individual team chassis dyno testing is suggested.
RPM: Engines should be limited to 4500 RPM. Teams run a risk a valve float above that RPM.
NORAM Enforcer clutches have shown a much higher durability than the NORAM Mini-Cup clutch.
When using a NORAM Enforcer clutch, install a spacer behind the clutch to eliminate the chance of the clutch sliding towards the engine.
Use Loc-tite on the crankshaft bolt and torque to 95 ft/#. This reduces the chance the bolt will come out, dropping the clutch on the track.
