Saturday, August 16, 2014

A Summary of Pan Am Classifications (Draft)


A SUMMARY OF CLASSES OF CARS
IN LA CARRERA PANAMERICANA
(DRAFT)

General Rules: no turbos or blowers, no fuel injection, original body work and frame. 600 CFM carbs for V8s, multiple carbs for European sports cars.  0.040 overbore allowed in most classes. Headers and modern disc brakes allowed in all classes. DOT tires, minimum tread wear 60, no shaved tires.  Six-point roll cages and other safety measures comparable to FIA Group N rally cars (not vintage cars). Fiberglass parts or bodies allowed on some cars with permission.  No station wagons or pick-ups.
There are six major classes of cars:  Competition, Historics, Original Pan Am, Exhibition, Hot Rods, and Concept cars.  Please note that this event is less about period correctness than safety and speed.
1.     Competition Cars, 1940-1954 – highly modified cars that just look old

A.    Turismo Mayor -- sedans, up to 360 c.i. engines, iron block, alloy heads, Jerico transmissions, five speed,    coil-over suspensions front and rear, min 3300 lbs, 16” rims  

B.    Turismo Production -- sedans, same as Mayor, except 305 c.i., iron heads on V8s, four-speed

C.    Sports Mayor – two seaters over 2000 c.c., coil-overs, replicas allowed with permission

D.    Sports Menor -- under 2000 c.c., two seaters, coil-overs, replicas allowed with permission   

2.       Historics, 1955-1965 or later, 1972  -- these cars must be more stock than Competition cars   

A.    Historic A -- four cylinder sports cars and sedans to 1965 or later in some cases
B.    Historic A Plus – four cylinders sports cars and sedans to 1972 or later
C.    Historic B -- six cylinders sports cars and sedans, 2400 c.c. limit for Porsches, 4.2 liter for American six cylinders.  
D.    Historic C -- eight and twelve cylinders, limited to largest engine generally available in 1965 model, some models up to 1972 are allowed; must weigh minimum 2800 lbs to carry a four-barrel carb.  See “continuation rule” below in Notes.

3.     Original Pan Amsedans and sports cars that were eligible to run the event in 1950-1954.  These cars must look like the originals (body and trim) but are allowed:  headers, aluminum radiators, disc brakes at all four wheels, 12 volt, modern ignitions, etc. Four speed transmissions in models of cars that were not available with manual transmissions in 1950-1954.

4.     Exhibitionif a car does not qualify for any of the classes above, it may run in Exhibition with the prior approval of the Organizers.  These cars are listed in the daily results but not in the final results.

5.     Hot Rods – in 2014 the Organizers created this class.  These are hot rods that were common in the years of the original race.  They may be prepared like a Turismo Mayor car, but are limited to 306 c.i. and must weigh at least 2800 lbs.

6.     Concepts – in 2014 the Organizers created this class.  These are one-off cars, often displayed in car shows as a future design.


Notes
This summary is just that.  Read the published rules of the event for the details.  For just about every rule, there is an exception, and the Organizers can waive just about any rule since they decide which cars are allowed to enter.
The “Continuation Rule”:  In the Historic classes, later model cars may be allowed to compete if its chassis and engine are essentially the same as the model of that car manufactured in 1965, or in the case of Historic A Plus, 1972 models.  In other words, the later model car should not have a mechanical advantage over the 1965 model of the same car and look about the same.  And in Historic A Plus it is possible to run a modern engine of up to 1600 c.c.
Limits on Speed:  the following classes are limited to 144 MPH by use of a MSD rev limiter: Turismo Mayor, Turismo Production, Sports Mayor, and Historic C.  See rules for the chart of variables:  rear-end gear, tire size, and other factors.  It assumes a top gear of 1:1 ratio.
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