Welcome to the Trans American Championship season of 1972! Where we race cars!
Rules
Sedan or coupe body
Touring cars
Trim year: 1972 or earlier
Engine variant year: 1972 or earlier
Engine: No race parts
Aspiration: Naturally aspirated only
Maximum wheelbase: 2.94 meters
No convertibles
Fuel: 98 Ron Super
Car: No race parts
Drivetrain: RWD
Aerodynamics: 2 fixtures maximum
Safety: Standard 60s or better
Techpool: $25,000,000 max
Max approximate cost: $40,000
Over 2.5L
Maximum engine size: 5 liters
No independent rear suspension
Rim diameter: 14 or 15
Rim diameter must be the same for both axles
Minimum weight: 1400 kg
Fuel system: 4 barrel single carb only
Under 2.5L
Minimum weight: 1 lbs per engine cubic centimeter
Submissions:
You may submit 2 cars, 1 in each category
Model name should be: TAC - Name
Engine family name should be: TAC - Name
There are 2 classes of cars. Under 2.5 liters (engine size) and over 2.5 liters size. Both classes will race at the same time.
All cars will be entered into an advanced simulation program of mine own design which will simulate the race on various tracks.
How simulation works
Higher drivability reduces the risk of crashes
Higher sportiness make cornering easier
Higher reliability means less likelihood of mechanical failure
Higher prestige increases base fan count
Higher fuel efficiency means less pit stops
Each pit stop will refuel the car. It take 2 minutes.
Rules deliberation will continue until November 1, 2024, and submissions will close on December 12th, 2024 (please tell me what rules I should add I probably forgot something)
Rules sound good so far, but will you be using a baseline track time for each car to base these stats off of? Otherwise it would be pointless to make a fast car and much easier to just focus on the stats.
95 RON is an unleaded blend, but it was not in widespread use by 1972. Also, the complete ban on all functional aero fixtures (which I’m assuming includes undertrays) makes little (if any) sense given the presence of small front and rear spoilers in the various cars being entered in real life at the time (nonfunctional spoilers simulated through body moldings are exempt, though).
The entry-level class is for cars whose engines displacing 2500cc or less; the only other class accommodates cars whose engines have a displacement greater than 2500cc.
It is wild. i think he just wants some cars to play around in beamng and he’s going to ghost us lol (if its not clear im joking, i dont think he has ill intentions)
If you’re trying to follow the rules closely, I have a few suggestions. Limiting engines to 5 Liters would be important, and spoilers were allowed and common. I also think the tires would have been racing compounds (crossply), certainly not stock tires. And while the base cars and engines have to be homologated, lots of modifications were allowed or required.
I will also add that rules for Trans Am racing changed from year to year, so if you want this to represent 1972 specifically, there are a few regulations that only came about after 1970 or so, like the min weight of 3200lbs and requirement for single 4 barrel carbs.
Here’s a collection of the original regulations if you find it helpful.
O2.5L cars were always under 5 Liters (305 cu.in.). This is buried in the 1972 regulations in section E (Engine and Drive Train).
O2.5L cars were not allowed to have independent rear suspension—they all had solid axles.
Wheels were 14" or 15" diameter, maximum 8" rim width. Maximim track width was 64". Front and rear rims must be same diameter.
Minimum weight (with full fuel tank—no driver) was 3200lbs (1451kg).
Any exhaust headers and mufflers could be used, including straight pipes.
Any pistons and camshaft were allowed. Any steel or cast iron con rods were allowed.
Dual 4-barrel carbs banned since 1970. Single 4-barrel carbs with a specific bore mandatory. Any intake manifold was allowed.
Under 2.5 Liters
Minimum weight determined by engine type and capacity (between 1.0 and 1.4 lbs per cc engine capacity).
Maximum rim width 6" for <1.3L, 7" for >1.3L.
Any pistons and camshaft were allowed.
All Classes
Wheelbases over 116" (2.94m) were not allowed.
Convertibles and sunroofs not allowed
Headlights and parking lights removed and either covered or used as air duct.
Front and rear spoilers allowed if homologated. Standardized front spoiler allowed if no stock one homologated.
Stock front and rear bumpers required.
And for clarity for those who aren’t familiar, the O2.5 category was exclusively muscle cars, so all 5 Liter pushrod V8s. The U2.5L category was mostly European and Japanese sporty touring cars, like Datsun 510s, Alfa GTAs, etc.
Edit: One other thing. High octane leaded fuel was available back then. GM recommended 103 octane (RON) fuel for the L88 engine it sold for racing use. That engine had a 12.5:1 compression ratio, as did many of the engines used in Trans Am racing, so it’s reasonable to expect fuel of at least 100 octane would be used in racing. 102 RON was even widely available at brand name gas stations.
