Sunday in SCCA World Challenge GTS competition, the Ford Mustang Boss 302 contingency staged a protest against the series by parking their cars in pit lane after the initial formation lap.  The reason for the protest was actually twofold.

The primary reason for the protest was driven by high engine temperatures caused by the very small restrictor the Boss 302 GTS Mustang is required to run to reduce the horsepower of the Mustang.  This causes unusually high engine temperatures and all Mustangs were experiencing high engine coolant and oil temperatures.  Two Mustangs failed to finish due to engine related issues. Some engine oil temperatures were in excess of 310°F which is quite a bit higher than normal. Engine coolant temperatures ranged from 240°F to 280°F.  This is significantly higher than normal operating temperatures and puts the engine’s computer into protect mode.  This demonstrates that the restrictor has a compounding effect on the Mustang’s ability to make horsepower and be competitive. The competitors collectively chose not to race their cars rather than risk further damage to the engines in their cars.

 

 

The secondary purpose of the protest was to bring attention to the current rules package for the Boss Mustang. The series has a very difficult task in trying to create parity between vastly different vehicle makes that achieve lap times in vastly different ways.  Some have a power advantage, some have a stopping advantage, some have handling advantages, etc…  The Mustang owners and drivers collectively and unanimously feel that the SCCA’s method of creating parity is not working and leaves the Mustang with a significant handicap in many areas, and an advantage in NO area.  The Boss Mustang teams held meetings with series officials throughout the Mid-Ohio event in an attempt to regain some level of competitiveness, but those discussions proved fruitless.  The teams collectively felt that their voices were not being heard and staged a protest to bring more attention to this matter.

The top finishing Mustang in Saturday’s race was 10th place.  The fastest lap time of the fastest Mustang was some 1.4 seconds slower than the front running cars.  All of the top six cars were greater than one-second clear of all Mustangs.  The three fastest Mustangs were within 0.1 seconds of each other.  This demonstrates that there is a clear disparity between the Mustang and all other makes.

The following teams agree the use of inlet restrictors are the direct cause of the extensive engine overheating issues leading to eventual failures. In consideration of the high replacement costs of a new Boss 302 engine and the replacement of failed components due to the high heat stresses being applied to these engines,  and the resultant safety issues stemming from exhaust fumes entering the car, it is agreed SCCA must stop its parity by restricting the Fords.

Failures of note are:

* Tiger Racing:  Two engine failures due to catastrophic engine over-temps

* JVK Motorsports:  Elevated ECT

* Rehagen Racing:  Exhaust Manifold blowout, cracking and extreme driver compartment heat.

* GSP Racing:  Extreme Driver compartment hot enough to melt the rubber soles of driver's shoes.

* Autosports Development:  Elevated ECT

* R & C Motorsports:  Exhaust manifold failures

First an understanding is required of the layout and configuration of the Boss 302 air filter box, air temperature sensor (ATS) and the Mass Airflow Sensor (MAF).  The air enters the air filter box and a temperature reading of that air is given to the ECU for a calculation on air density first.  The MAF, located within the tube from the airbox works by the velocity of the air flowing over the sensor sends a voltage reading indicating the mass of air flowing into the engine. Load variables are then added based upon engine coolant temps and load based on manifold pressure.  These variables are finally checked during the feedback signal from the wide band oxygen sensors located in the exhaust pipes. Unfortunately, Oxygen sensors are typically not used for engine calibrations at Wide Open Throttle during high load usage which then demands all fuel-based calculations are made from MAF inputs.

The problems begin when using such a small restrictor in the inlet of the throttle body, so far from a calibrated air meter being fed ram air, an increase of pressure at the sensor reducing the airflow velocity across the MAF sensor element, falsely indicated less than actual airflow to the ECU that it needs less fuel. As the airflow converges at the inlet restrictor by the throttle body, the airflow has to accelerate to get through the reduced size air restrictor (think thumb on end of garden hose) which increases its velocity and its pressure. ADD to this equation the A/F ratio is calculated using an air temp sensor mounted at the forward end of the airbox which is MUCH higher temp then the expanding airflow coming from the restrictor which will have a significant temp drop due to its expansion. Ever see a tunnel-ram intake sweat and chill due to this design? Take a second look at the tunnel ram style of intake manifold such is being used on the Boss 302.  This convergent divergent airflow is the basis of all air-conditioning systems where the resultant air is now cooler and thus more dense than the previous readings.  This denser air charge now carries with it the two-fold problem of an initial miscalculation of proper and actual airflow into the engine coupled with the miscalculation of the actual air mass in the intake and then third factor of a much higher airflow velocity through the port into the cylinder creating an extremely lean fuel mixture.  This is chemistry for detonating an engine which is being pushed to its calibrated limitations during race lap after lap until something fails.

We feel that SCCA Pro World-Challenge has lost sight of what has brought so many people to love World-Challenge Racing... the Professional sport at a reasonable cost in GTS competition. The Ford Mustang Boss 302 S should be the standard, not the exception.  Ford Racing has engineered a very affordable and race ready product anyone can buy out of the Ford Motorsports parts catalog and has continually developed its platform each year with feedback from its racers to have the best performance package for the dollar spent.  The GTS Category should be a "Pony Car War" class with vehicles in competition which can be purchased at any dealership and raced for a reasonable cost. Rule mandates for competition should be done with proper consideration given to costs, calibrations and ease of implementation.

We challenge SCCA Pro World Challenge to commit to the immediate implementation of new rules and standards.  We offer our collective support to work with Tech to find a suitable and affordable means to make a competitive racing event which is safe for all who participate.

 

On Monday, Ford Racing issued the following statement:

 

"Ford is very proud of the Boss 302S and all the privateer teams that choose to campaign this production-based race car in SCCA World Challenge and other race series.

“Competitiveness is critical to the success of any racing series. The actions taken by the individual Ford teams on Sunday highlight the difficulty that World Challenge has had establishing and maintaining parity in the GTS class throughout the season and the resulting frustration of the competitors.   We understand and share the Ford teams' concerns over the competitiveness and the resulting rules changes that have hurt them on track.

“Ford Racing is committed to continuing to work with the SCCA Pro series and the Boss 302S owners to establish a rules package that will allow all vehicle makes to be competitive in the exciting GTS class.”