IMSA Automation GT Challenge '78

Brought to you by @ramthecowy and @Speedemon

The thunderous roar of V8s. The scream of a six cylinder. Pierced by the wail of a high strung 4 banger. Any and every car made before 1978 qualifies for entry - anything from hatchbacks to wagons to proper sporty coupes to serious hypercars. This is the 1978 Automation GT Challenge. Build the most unhinged, unbelievable monsters based off the most unsuspecting plebian vehicles to exist and fight your way up the grid for victory. Battle against luck, design gorgeous liveries, go wild, because in the Automation GT Challenge, there are few limits. Winning means eternal glory for the team or company, for this challenge is not an easy one, it is not a minor or unknown one - and this is exactly the thrill and attraction of this race. A season of grueling long distance sprints and short bursts of wheel to wheel battling… the AGTC has it all. Who will be the one to dominate?

Big thanks to @ramthecowy who not only boarded the hype train but also helped finalize the rules, and also helped set up this post so the challenge could be held. If you have questions you can ask me (@Speedemon) or Ram. Another big thanks to @DeusExMackia who kindly lended the ATCC calculations to me, which I used as a base for the AGTC Endurance Calculations.

How does this challenge work?

The Automation GT Challenge is based off the IMSA GTX, in turn, FIA Group 5 regulations adapted for Automation. First of all, this must be clarified. Your eyes do not deceive you, there really are no power-weight regulations to balance out different body styles or aspirations, much like the real IMSA GTX. However, like reality, raw laptimes are not everything. Indeed, the difficulty of the driving is very much factored in, and similarly fuel consumption too.


The calculations are based of @DeusExMackia’s ATCC calculations, but edited for endurance races with the addition of mechanical failures and crashes. The calculations will be tweaked and refined in the time before the first race (Daytona 24 hours.) Lap Times, Sportiness, Drivability, Trim Reliability, Engine Reliability and Economy are all factors in the calculations. But to keep one car from finishing the races in first every time and to replicate the unpredictability of auto racing there will be chance, also affecting if you crash or have a mechanical failure.


click here to view the table
Position Points
1 150
2 140
3 130
4 120
5 110
6 100
7 90
8 80
9 70
10 60
11 50
12 40
13 30
14 20
15 10


24 hours of Daytona Road Atlanta (100 Miles)
12 hours of Sebring Laguna Seca (100 Miles)
Portland International Raceway (100 Miles)
Mid Ohio Sports Car Course (100 Miles)

Deadline: August 13th, 10:00PM EST

Of course the submission format is:

Model AGTC - username
Trim Free
Engine AGTC - username
Variant Free

It is crucial to read all fine print.



These rules apply for the entire car, trim and engine. You are allowed:

  • A maximum of 15 quality points you can use in total, 8 at most in one go
  • and a minimum of -8 quality points
    Remember that minimum of -8 means you are not allowed any value below -8, NOT that -8 is the highest amount permitted and you can use anything below that. To repeat, all quality sliders must be between -8 and +8. Using negative quality will not increase the amount of positive quality points you are allowed.


You must have 2 trims, one production trim and one race trim. The model year can be anything, but be sure that the race engine variant and trim are set to 1978. You must use the same drive type that the original production car did. All morphs except the fenders must be the same as the original. The engine placement must remain the same as the production trim. Ensure you are using non-Barth and CaptainD00m bodies and fixtures. PM @Speedemon if you will change from a variant with chrome or plastic trim to one without and clear that.


The engine family must be one used in any production trim of that model. The variant capacity can be changed, meaning that the race variant can have a different bore, stroke or capacity altogether. The engine aspiration may be changed.

  • 98RON super leaded fuel will be provided.
  • You must use race intake
  • The engine must have 30 reliability or more

Your engine and car must conform to the table below.

Engine capacity to weight regulations

click here to view the table

Maximum Engine Capacity

Minimum Vehicle Weight

850 cc

675 kg

1000 cc

735 kg

1150 cc

800 kg

1300 cc

860 kg

1600 cc

915 kg

2000 cc

970 kg

2500 cc

1025 kg

3000 cc

1065 kg

3500 cc

1115 kg

4000 cc

1155 kg

4500 cc

1190 kg

5000 cc

1200 kg

5500 cc

1240 kg

6000 cc

1255 kg

>6000 cc

1330 kg


  • Minimum 35 safety
  • Manual transmission
  • Semi slicks
  • Magnesium rims
  • Fully clad undertray
  • Basic interior
  • One wing and one lip only
  • All locking differentials are banned


Sounds great, nice fine print.

Only problem is that everyine will go turbo. If that is a problem at all…

Meanwhile I’ll be going the Pushrod V12 Pick-Up truck route…

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I didn’t do the calcs but I’m hoping Speedemon has stuck in a great big penalty for low drivabilities because I’m going NA :laughing:

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Question: does using negative sliders use your positive slider pool, or is that 15 positive points only?

Get ready for the Erin TI-76 to come to life at last. A steroid-packed attack dog version of the Merna.


Bringing a Calculator are you :stuck_out_tongue:


Holy schnacks, I didn’t realise it had the same name… :smiley:

As it says you have 15 positive sliders to use throughout the entire car. That amount doesn’t change whether or not negative sliders are used. The 8 negative points allowed are seperate from the 15 positive ones allowed. If that made any sense.

I kind of want to…


If I could request that the OP be changed to read thus:

All tech sliders must be between -8 to +8 inclusive
You may use up to a total of 15 positive tech points over the entire car, trim and engine
Using negative tech points will not affect your positive tech point total

That would be perhaps a bit clearer. And also confirms that there is no limitation on total negative slider.

The NTX looks more like a ute than a truck, but I still like the look of it anyway. That thing looks and feels like it can devour smaller cars whole!

Anyway, are there really no limitations on price (including markups) for this series?

What’s a reasonable driveability for 1978? G&W want in on this.

“Reasonable driveability”?

You want a drivable IMSA GTX car?



You wanna laugh at me? Okay, then. See you on the track :rage:

JK. My car’s rubbish to start, just wondering how much :man_mechanic: it needs to “race”…

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To be fair, it’s a pretty simple recipe.

  1. Squeeze every last motherf*cking horsepower out of the engine
  2. Make it as light as humanly possible
  3. Ensure the tires are wide enough to land a small airplane on

Ok hold on there I’m not even sure that’s what speedemon meant it to say so… @Speedemon?

@strop You can use up to +8 quality points and up to -8 quality points per slider, with a total of 15 positive points usable for each section (Model, engine, trim) not each individual tab, meaning if the sum of all the positive quality points you used across a section is greater than +15, your car does not meet the regulations. If a slider shows more than +8 or -8 quality points were used your car doesn’t meet the regulations. Negative quality points do not increase the amount of positive quality points available, so if you have -2 quality points on a slider, you cannot use +17 points for that section.


I want in, but I have a small question:

If i want to build, say 1400cc engine, do I have to make the car weigh at least 860kg (1300cc limit) or 915kg (1600cc limit)?

1600 limit. You are above 1300cc.

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