When you think of multiclass racing, you picture high-powered prototypes passing lower-class cars at amazing venues like Le Mans and the Daytona 24 Hours. However, there are also short-form multiclass series on iRacing that feature cars that are not as intense to drive but still offer the opportunity to race against other categories of cars at the same time.
iRacing’s Sim-Lab Production Car Challenge is a short-duration multiclass series that provides beginner drivers with all the excitement of racing four different categories of tin-top cars.
The Cars
The Sim-Lab Production Car Challenge features four different classes of cars from four manufacturers, ranging from the 2.0L 181hp Mazda MX-5 to the BMW M4 GT4, which is designed to train the GT and prototype stars of the future.
Mazda MX-5 Cup
Almost all iRacing rookies start their career in the Mazda MX-5 and quickly learn how to pedal this rear-wheel drive roadster thanks to its balanced and exciting handling. It may not have much power, but it more than makes up for it with a handling model that’s easy to learn initially but very difficult to master.
The MX-5 is all about momentum and load transfer. There’s no downforce to speak of and not much power, but once you figure out how to carry speed by being smooth with the controls, it’s a joy to drive.
- If you want to learn how the master this car, make sure to check out our guide to the Mazda MX-5 here.
Toyota GR86
Blessed with amazing handling and a decent amount of power, the 2.4L rear-wheel drive Toyota GR86 is a true driver’s car that is tremendously fun to race. Similar in certain aspects to the MX-5, it does, however, have a small amount of downforce that helps improve its cornering ability and therefore is slightly faster over one lap.
It can handle being pushed hard with a wide slip angle allowing drivers to take it past the limit and still bring it back. Just like the MX-5, it’s free and, therefore, a cheap option for entering multi-class racing.
- Want to learn more about the GR86? Take a look at our guide to it here.
Renault Clio
Weighing in at just over 1000KG, the Clio is a small, 200hp front-engined front-wheel drive hatch that’s nippy and handles well. However, without much weight, it can be a handful if you’re not careful with the throttle, especially when entering corners. Sudden oversteer can be a problem if you don’t come off the throttle smoothly.
Overall, the Clio is quick but needs the driver to follow smooth lines and not be aggressive with inputs. Slow in, fast out tends to work well, with gentle brake inputs helping with load transfer due to its lack of downforce.
BMW M4 F82 GT4
With the Ford Mustang FR500S having been carted off to retirement, it has been replaced by the BMW M4 F82 GT4. Designed for entry-level GT regulations, the M4 is heavier and doesn’t feature as much downforce as its GT3 cousins.
Despite its turbocharged 3.0-liter inline-six engine not sounding as muscular as the Ford’s, the powerplant provides way more power at 530 hp. While it tends to lumber around more than a GT3, it’s still more agile than the old Mustang was. Due to its heavier weight and lower downforce levels, making sure not to overdrive corner entries is important to prevent the front tyres from losing grip.
It also comes with traction control and ABS, so you won’t have to worry as much about suffering from wheelspin or locking up the tyres under braking. Fancy getting up to speed with the BMW M4 GT4? Then why not take a look at Coach Dave Academy’s in-depth guide to the contender?
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Race Format
Sim-Lab Production Car Challenge Races are 25 minutes long and begin from a rolling start procedure after the usual private 8-minute qualifying session. Races start every hour at half past, e.g. 5:30, 6:30, 7:30, etc.
Since it’s multiclass, you need to focus only on racing cars in your class and steer clear of drivers in other vehicles. You’ll need a Class D license or a Rookie license with a Safety Rating of 4.0 to enter the series.
Races tend to be chaotic, especially at the start, so it’s recommended that you focus more on getting a clean start and less on trying to make risky overtakes. 25 minutes is plenty of time to work your way up to a good position, especially if you stay out of trouble.
Multiclass etiquette
If you’re a rookie, we strongly recommend that you join practice sessions with several drivers on track, to understand how to pass slower-class cars and how to get overtaken by faster-class cars. With the Sim-Lab Production Car Challenge positioned as an entry-level multiclass series, it’s designed to teach you the ropes of racing around other types of cars, so make the most of learning before graduating to a championship such as the IMSA iRacing Series!
You should also map the Black Box Relatives window to your steering wheel to have real-time info on how far cars are in front and behind you. You need to watch this window like a hawk to make sure you don’t impede other drivers, as well as to plan for overtakes. It’s better to practice, make mistakes and then learn from them than to spin and crash in an official race and ruin your race and the races of other drivers as well.
What’s so special?
As mentioned before, the Sim-Lab Production Car Challenge is a short-format multiclass series that gives you all the thrills and spills of multiclass racing without some of the downsides:
- Races are only 25 minutes long and occur every hour
- Two of the cars are free
- Some of the tracks are included in the iRacing base content
- You get to learn how to race multiclass with the same MX-5 you learned to drive as a rookie
- There are no pit stops, refuelling or tyre management to worry about
Final thoughts
Multiclass racing provides a thrilling racing experience once you master traffic management and maintain solid, consistent lap times while passing slower cars. Thanks to the Sim-Lab Production Car Challenge, you don’t need to worry about dealing with rapid prototypes like the Ferrari 499P.
It’s an excellent series for beginner drivers to learn multiclass racecraft, and will set you up perfectly to move up to series like team-based endurance events, which consist of races as long as 24 hours.
