Scorpion S1 Formula 500

Scorpion S1 Formula 500 1.0.1

Login or Register an account to download this content
Buy me a coffee via Paypal

Please support this modder with a small donation.



Originally introduced in the SCCA club racing rules as Formula 440 in the early 80s, Formula 500 is a unique low-cost racing class built around inexpensive, low-displacement motors, minimal aerodynamic devices, and simple-but-effective suspension components.


As originally conceived, the class used a two-stroke snowmobile engine and associated CVT transmission to drive a go-kart style solid rear axle. In 2014, lightly-modified 600cc motorcycle engines were added to the formula to broaden its appeal. To keep suspension costs down, the class uses neither dampers nor springs – instead, 2” diameter rubber pucks take the place of coil springs, and damping is provided by clamping friction between suspension links and the chassis. (Snowmobile engines and hockey-puck-based suspension? No points for guessing what part of the United States F500 comes from!)

That’s not to say that these cars are primitive, though. F500 car designer Jay Novak (after hours from his day job in Ford’s NASCAR program) developed sophisticated suspension bellcrank geometry to get linear spring rates from the rubber pucks, which is replicated across most class-leading cars today. CFD analysis has also lead to the widespread adoption of prototype-esque bodystyles with partially-faired wheels for drag reduction, and as a result these cars can see speeds in excess of 140 miles per hour in a straight line. The simple underlying systems, however, keep build and operating costs low – about half of the cost of a US-spec Formula Ford car – and enable tinkering owners to design, tweak and optimize their cars with home-shop tools and know-how. A competitor in the related F Modified autocross class recently designed and built an entirely new car in his garage, over the winter off-season, and took home third and first place wins in the open and ladies’ classes at Nationals the following year.



The car represented here is a Scorpion S1, one of the few F500 chassis still being produced new for purchase. It is equipped with an aerodynamic carbon-fiber body and is powered by a Suzuki GSXR600 motorcycle engine and paddle-shifted sequential transmission. Cars based on this chassis have placed highly at the annual SCCA Runoffs every year since its introduction, with multiple overall victories.

Features include:
  • 20 different skins, based on real-world liveries of SCCA F500 competitors
  • High-fidelity vehicle physics developed by @mclarenf1papa of IER Simulations and validated by race-winning F500 drivers
  • Fully-moving suspension components
  • Functional and fast AI (it will come within a couple seconds of the F5 lap record at most circuits)
  • Custom SFX


Many thanks to IER Simulations, who developed the physics for this mod, as well as Matt Strand of Satellite Racing, who supported the project and provided lots of reference models and photos. Thanks as well to real-world F500 drivers Ryan Mayfield and (back-to back Runoffs F5 champion) Sven de Vries, who provided testing and feedback to ensure that the car looks, feels, and drives like the real thing. Finally, thanks the SCCA F500 & F Modified community on Facebook for their interest, enthusiasm, beta test reports, and livery reference images.





Help! When I try to load the game with this car, it crashes the game/flies into space/drives like it’s on ice!
The suspension physics rely on @Stereo and @mclarenf1papa ’s Cosmic physics extension, which is only available in CSP version 0.1.79 and above. The car may or may not load in earlier versions of CSP, but it will behave unpredictably at best. You must use a supported version of CSP for this car to load and drive properly.

I installed the right version of CSP, but I’m still having problems!
This issue was noted in private testing and appears to be a problem with CSP. Downgrading to an earlier version and then reinstalling 0.1.79 appears to resolve the issue in most cases.

AI cars are being launched into the air on certain kerbs!
You may be using a preview release of CSP 0.1.79; this behavior has been largely corrected in the public release. Please update to the latest public version.

Latest updates

  1. v1.0.1 - Now with 50% less cheese grater to the ears!

    Minor update: Version-locked the car to CSP 0.1.79 or greater Included a revised, more pleasant...

Latest reviews

Great mod, very fun to drive, superfast!
Only drawback is de missing Protyres support.
It looks like some files are not accessible for Protyres in data.acd, preventing Protyres to advice over temps and pressures.

Is it possible to fix this, either creating an update or is there a workaround I can can apply to the mod?
Very well made and they almost entirely like the real thing, these have always been some of my favorite cars in SCCA. Thank you for making this mod.
Awesome car, awesome physics (thank you IER) and whole lot of fun :)
Excellent job / good fun. Thanks so much.
I'd been looking forward to this mod & it doesn't disappoint.
Thank you! Great work.
Wonderful little car!
Quick and challenging to drive.
Unfortunately doesn't load with csp 0179 preview5 but does work with 0179.
Thank you for the mod!
Active SCCA club racer here. This mod is awesome. These cars are awesome. I didn't get to watch the F500 race at the Runoffs this year, but I watched at Indy, and that race was epic. The mod is wonderful, I love the real-life skins. Physics seem to be spot on. Wish there were some of these cars that still operated here in New England. The F500 track record at Lime Rock is 53.152 set in 2008. Let that number sink in a little!
Heads up for some people: just because the car doesn't handle like you expect or think the car handles badly, doesn't mean the physics are wrong.

You can be sure that IER knows what they're doing. Probably more than any other physics modder on AC.
What bothers me personally are the paddle shifters that are not connected to the steering wheel. I prefer to drive with the steering wheel hidden. Like this it looks awful. If the paddle shifters had a nicer brushed aluminum texture it would be ok with me. Handling is fun, but for my taste the brake balance is too rear-heavy in the default settings. (have CSP 1.79)

P.S: Sorry for my rude criticism. I am an ungrateful contemporary. If it were possible I would have given 4 and a half stars.
Fair's fair, the aluminum texture is a bit plain. I don't think I can hide the paddles from view, but I can dress them up a bit...
Great job! A lot of fun to drive. Well done!
@Wietie I use the Yamaha YZF-R6 sound from the Cross Car Camatos mod
Fun little car. Way to loose. Operates well with CSP 1.74. Please tighten it up some or open the data file.
So what's happening is that CSP 0.1.74 will load the car, but since it can't understand the rear suspension it acts as if it's completely locked in place. That makes the car undriveably loose -- if you update to CSP 0.1.79 it'll handle much better.
Thank you and everyone involved for this amazing creation! After around 15 minutes to get somewhat of a feel for this small vehicle, it's incredible! Exrtremely fun to race!
This was one of the WIP mods I was most looking forward to and I am very glad to see it make it to full completion and public release. Truly a very unique and challenging car, keeps on on your toes throughout each corner, really an anti-thesis of most "point and shoot" modern entry level single seaters. It is nice to have enough skins for a full grid too. Big thanks to the people who were involved in the mod's creation.
Let me start out by saying this car has great potential, it's decently "challenging" while remaining a lot of fun to drive.
I did some runs around Donington Park and I very much approve of the physics work (a mod without stolen Kunos physics, hallelujah!).

The model looks decent, even if it is a bit dense in places, and comes with a full set of LODs (which is seemingly becoming scarcer on mods released here), so bonus points there.

The SFX is the main reason why I'm knocking a star off here, it really makes your ears hurt after a few laps, which obviously isn't very fun.
I would suggest either reworking it or looking for an alternative.

One minor visual bug noted, but I'll place that in the discussion thread.

All-in-all a good mod with lots of potential to be superb!
Fair point regarding the sounds. This is my first whack at FMOD, and unfortunately it sounds a bit like it. I'm working on a less grating sound pack for a future update... or if somebody who knows what they're doing wants to have a crack it, I wouldn't say no! :D
The car feels a bit 'wobbly' - mainly during cornering and braking - and the sound is 'meh' but it definitely has potential. Thank you for this!

Latest News

File size
49.6 MB
First release
Last update
User rating
4.69 star(s) 16 ratings

More mods from Thrashy

How long have you been simracing

  • < 1 year

    Votes: 215 14.3%
  • < 2 years

    Votes: 154 10.3%
  • < 3 years

    Votes: 149 9.9%
  • < 4 years

    Votes: 115 7.7%
  • < 5 years

    Votes: 216 14.4%
  • < 10 years

    Votes: 179 11.9%
  • < 15 years

    Votes: 118 7.9%
  • < 20 years

    Votes: 80 5.3%
  • < 25 years

    Votes: 64 4.3%
  • Ok, I am a dinosaur

    Votes: 209 13.9%