A guide to multiclass racing on iRacing
Image credit: FIA WEC

A Guide to Multiclass Racing in iRacing


Multiclass races are often the most thrilling. But how does one navigate traffic and survive? Here’s a guide to competing in multiclass races in iRacing.


Some of the most popular series’ on iRacing feature multiclass battles. The IMSA Series, Production Car Challenge and European Endurance Series all see cars of different speeds race on the same track at the same time.

The thrill of fighting for position all whilst dicing through slower traffic is second to none. It’s clear to see from the popularity of the aforementioned iRacing series’ that the community loves this unique style of racing. But it seems many struggle to grasp the intricacies of multiclass events. This year’s Nurburgring 24 Hours sparked controversy for the many needless incidents caused by inexperience in dealing with traffic.

With that in mind, this is the perfect time to outline a few unwritten rules and agreements. Whether you’re a top class missile or feel like a lower class chicane, here’s our guide to multiclass races on iRacing.

What is multiclass racing?

Before embarking on the path to perfecting one’s multiclass racing skills in iRacing, it’s a good idea to know what this discipline actually is.

This is typically something one would experience in endurance racing. In fact, whilst expensive faster cars attract high-level professional racing drivers to an event, a grid is often completed with a selection of lower class cars. Traditionally driven by younger drivers or amateurs, sim racing sees racers choose their preferred category.

In many cases, multiclass racing sees fast prototype cars ripping around a circuit all whilst slower GT models compete in their own race. It’s important to know that, whilst the different classes are on track at the same time, they are not truly fighting between themselves. Instead, the individual classes battle for in-class position all whilst managing traffic. This typically makes for an exciting spectacle to watch and a heart-pumping experience behind the wheel.

iRacing Lower Class Guide

Whilst the majority of sim racing fans will prefer to race among the faster classes of a grid, running a lower class of car is just as fun. At Daytona or Sebring, this would be the GTD class. At the Nürburgring 24, the Toyota GR86 was the slowest car. Regardless of the model, the theory of driving a slower class of car in a multiclass event remains the same.

GT3 cars are the slowest class of car in many iRacing special events
GT3 cars are the slowest class of car in many iRacing special events. Image credit: iRacing.com

Although slower cars obviously race for position, they must also always keep an eye behind them. With faster cars incoming, it can feel like a helpless situation. But when done right, there’s plenty of time to be gained from following the guide lines of multiclass races on iRacing.

As with typical wheel-to-wheel racing, the most important thing to keep in mind is being predictable. Faster cars will have a much easier time passing a predictable car rather than a car weaving all over the track. This will save both cars buckets of time.

So how do slower class cars remain predictable? The easiest way to do this is to stick to the racing line. Whilst many think it’s helpful to move over and let faster cars through, it isn’t. Faster cars will be plotting their route past traffic from the moment they see a slow car. The minute a driver moves over to let a faster car through, it messes up the leader’s flow. This sort of unpredictability can lose both cars time and even create crashes.

This doesn’t mean you can’t leave the racing line. If you’re racing another car in class, focus on what you’re doing. A faster car’s role is to wait for the right moment to pass. One can even defend in an attempt to block a faster car in specific sections. Only do this well before a braking zone however. Do not throw defensive moves late in to a braking zone.

Simply slide over to the inside early on a straight leading up to a corner you don’t want to be passed at. The faster car should understand what you’re doing and wait for the next straight.

Top Class Rules

Lower classes of car in iRacing multiclass events must stick to their lines and almost forget about upcoming cars, but there’s a very different set of guide lines for faster cars. When driving a faster car through slow traffic, it’s crucial to make one’s car visible and to be patient.

In fact, one could blast through traffic in a fast yet unsafe way, making enemies as they go. But this isn’t the best way to go about events like these. In order to get to the end of the race in one piece, one must instead be patient and pick moves safely.

For this, make sure slower cars can see you. Pull out of the slipstream early to show your intent of making a pass. Alternatively, a flash of the headlights, whilst often interpreted as a sign of anger, is a great way to ensure one’s visibility.

The BMW M Hybrid V8 LMDh makes up the top class of many iRacing multiclass series
The BMW M Hybrid V8 LMDh makes up the top class of many iRacing multiclass series. Image credit: iRacing.com

Now that upcoming traffic can see you, it doesn’t mean you’re entitled to send a divebomb up the inside at the next turn. As already mentioned, passing slower cars is all about patience and avoiding slowing either car up as much as possible. Typically, this involves not going side-by-side through an apex. Either complete the move prior to a corner or fly past on corner exit.

In fact, the best way through traffic is to keep momentum high. If you can’t get past before the braking zone, drop back. This means you can take your normal racing speed through the next corner and get a slingshot onto the next straight.

Multiclass Racing on iRacing

Overall, multiclass racing on iRacing is all about respecting your fellow racers. If you’re a faster car, you must make sure to not slow traffic down. But if you’re in a slower class, you must keep an eye on cars coming up behind you. Choosing which class to compete in comes down to which models you enjoy driving and how you want to spend your race.

As a top class runner, prepare to see your rivals escape your reach as traffic slows you. As a lower class competitor, you are sure to spend your race checking the mirror and having “blue flag” shouted in your ear by the crew chief.

If you really want to suffer, a middle-class entry can be a terribly stressful yet rewarding experience. Fighting for position all whilst making your way past moving chicanes and seeing missiles fly by you is a thrill like none other.

What is your top tip for multiclass racing on iRacing? Tell us on Twitter at @OverTake_gg or in the comments down below!

A petrol head and motorsports fan since the early days, sim racing has been a passion of mine for a number of years. The perfect way to immerse myself in my true dream job; racing driver. With lots of experience jotting down words about the car industry, I am happy to share my passion for pretend race cars here on Overtake!