Hello iRacing,

What a summer it’s been for motorsports. Between a brewing F1 title fight, dominant performances in INDYCAR, and NASCAR powering toward the Chase, real-world racing action has been relentless. That same energy is fueling iRacing, where we’re seeing all-time high participation across official series, packed special events, and incredible drama as our esports championships enter the final stretch. It’s truly a fantastic time to be a racing fan.

It’s an equally exciting stretch behind the scenes, where our development teams have hit major milestones across several flagship projects. NASCAR 26 has officially passed certification and is primed for launch on September 18th, loaded with new features and game-changing upgrades. Dynamic tracks advance both the tech and the on-track action, while the all-new Chase mode lets you jump straight into the heart of the championship. There’s so much packed in, though I have to admit, the new burnout celebrations are a personal highlight of mine.

Meanwhile, iRacing Arcade just landed on consoles, bringing an approachable, high-energy pick-up-and-play experience right to the living room – complete with four-player split-screen that my kids and I have already been tearing up. And how about the Euro Truck… To cap it all off, the team behind our upcoming INDYCAR title continues to make incredible progress as we gear up for release next Spring. 

Now, onto the sim itself and the real reason you’re all here for this update! The team is putting the finishing touches on the Season 4 build, and it’s shaping up to be a massive release – packed with core engine advancements, deep physics overhauls, new sim systems and UI features, and an unbelievable lineup of cars. Let’s dive in.

Tracks

With Season 4, we are excited to release three from-the-ground-up rebuilds of some iRacing track classics. I list these as new because each project was built upon all-new laser scans captured earlier this year, bringing the latest real-world enhancements to their iRacing digital counterparts. 

Road America is one of the great racing circuits in the world, and one of iRacing’s debut track partners all the way back in 2008. Referred to by some as the “Spa of North America,” Road America features racing across many racing categories, including GT, prototypes, IndyCar, and even NASCAR. With Season 4, Road America has been completely rebuilt and looks amazing. We are also adding two all-new configs that feature the bypass road in Turn 5, allowing for East and West Configurations.

Mid-Ohio Sports Car Course also joined the iRacing stable early on, back in 2010. This great racetrack was built to use its variable terrain as a feature, providing a fast, sweeping layout that is thrilling to drive while also technical and challenging at the limit. The new track looks amazing and offers exciting racing across the full range of road-racing machines.

The Milwaukee Mile has been a staple on our service for many years. Its one-mile length is perfect for a wide range of oval-racing racecars, and its design allows for high speeds balanced with technical, 9-degree-banked turns. Our new Milwaukee will also feature the debut of an all-new configuration – the Road circuit. This brings a classic Roval-style configuration to the track.

Each of these three new track scans will be added to their existing track packages – the result, you will get them automatically if you already have these tracks.

Track Refreshes

With Season 4, we have refreshed two of our most popular tracks.

Summit Point Raceway is one of the most raced circuits in all of iRacing. Unfortunately, it also has some of our most dated graphics. We have wanted to improve this for a while, and we’re happy to announce the work is complete. This is a from-the-ground-up upgrade, with every model and texture, tree, curb, surface, etc. rebuilt from scratch. Also upgraded is Jefferson Circuit. We’re excited for you all to experience it soon. 

Road Atlanta is another iRacing classic and one of the most popular road racing circuits in North America and worldwide. With S4, Road Atlanta has had a host of art upgrades, including new track surface textures, 3D curbs, foliage, new trees, and upgraded scenery. It looks awesome, and just in time for Petit Le Mans.

These updates will automatically apply to existing packages.

Cars

We’re excited to share details about our new and upgraded racecars this season. Let’s dive right into the details.

We’ve been actively working on bringing the Aston Martin Valkyrie AMR-LMH to iRacing for over a year now. It is a complex machine, and we refused to shortcut the physics and driving model just to hit a release date; critically, we worked to secure hard-to-acquire telemetry and engineering data, real-world chassis data, and direct engineering guidance and collaboration. That patience paid off: we’ve captured the Valkyrie’s unique blend of raw V12 power, extreme downforce, and intricate chassis dynamics as it battles at the pinnacle of sports car racing. We appreciate everyone’s patience while we dialed in every mechanical detail to the level you expect. The Valkyrie is dynamic, demanding, stunning to look at, and an absolute weapon on track.

I teased this one a few updates ago, and some iRacers were spot-on with their guesswork—we have partnered with Caterham Cars to deliver not one, but two of their incredible machines: the Caterham Academy and Caterham 420R. For those unfamiliar with Caterhams, they sit in a category of their own as true open-wheel sports cars: they feel like the ultimate cross between the immediacy, lightness, and exposed feel of a Formula Ford and the sports-car DNA of a heavily tuned Mazda MX-5.

Caterhams are based on the classic Lotus 7, a lightweight sports car that was available both factory-built and as a kit car. In fact, our own Dave Kaemmer built one and took me for a spin on the quiet roads near the office. Safe to say, the roads weren’t so quiet during that trip.

Built for novice racers, the Caterham Academy combines lightweight mechanical grip and deep-corner braking with high-drag, slipstream-heavy pack racing. Meanwhile, the 420R cranks up the intensity with a greatly stepped-up power-to-weight ratio that demands serious throttle control and precise inputs.

We’ve decided to package the Academy and the 420R together, so a single purchase gives you access to both cars. Initially, the Academy will be positioned in Class D series, while the 420R takes on Class C.

Car Updates

Our focus remains on balancing adding exciting new racecars with keeping our already amazing fleet up to date, taking full advantage of our latest improvements, tools, and processes. With Season 4, we have a handful of exciting updates to share with you.

The Mazda MX-5 has long been one of the absolute most popular cars in all of iRacing. It’s a fantastic introduction to motorsports for new iRacers, yet it has the ceiling to challenge the most skilled drivers in our Advanced series. If you want tight, competitive, fun, and forgiving racing, the MX-5 is the place to be. Some could say, why mess with success? Well, because we know we can do even better. 

There has been a complete re-engineering of the car, from bumper to bumper. Suspension system now utilize iRacing’s enhanced kinematic, which helps tune the suspension for better realism. Engine updates and driveline efficiencies have been tuned to reflect a past series update.The latest spec damper updates have been implemented. Our latest tire model has been integrated. Car handling was developed with pro MX5 drivers alongside in-house drivers. The damage model and aerodynamics have been enhanced to allow better realism for bump drafting and drafting in general. And finally, an overall art refresh was done to reflect the latest look of the car. The result is more intuitive driving feel, a smoother transition when catching slides, and closer, more predictable door-to-door battles.

A couple of years ago, we filled an important gap in our stock car lineup with the Gen 4 Cup car. For Season 4, we’re bringing you its little brother: the Gen 4 Grand National. Sitting just below the premier division during the pre-CoT era, this agile machine combines classic Gen 4 styling with high-momentum racing that rewards smooth pedal work.

The Grand National is being added directly to the ‘[Legacy] ARCA Menards Chevrolet and Gen 4 Cup’ package. Existing owners get it automatically for free on patch day, and with this release, the package sheds its [Legacy] tag (and price) and gains a dedicated official series running opposite Gen 4 Cup.

Gen 4 Cup and Gen 4 Grand National also have received a drafting model update.

For Season 4, our pavement Sprint Car gets a complete front-to-rear rebuild. Developed in close partnership with real-world and sim community drivers, this overhaul updates every underlying system to our highest technical standards – capturing the raw, fierce character of a modern asphalt Sprint Car with unprecedented fidelity.

Under the hood, power has increased, backed by a broader low-end torque curve and reduced engine braking that puts a true premium on pedal control into the corners. Beneath the chassis, the car transitions to our newest tire model with authentic construction and dimensions. Combined with completely overhauled suspension geometry, updated hydraulic braking, 2026 rulebook weight targets, and 1:1 garage adjustment limits, this update was comprehensive and utilizes our absolute latest tool and process improvements.

A massive thank you to the tight-knit community of Sprint Car racers who have championed this car since the early days of the service – this update is for you.

Sim updates

Physics upgrades

Last quarter, I touched on our multi-year roadmap to overhaul iRacing’s physics engine architecture. Today, the first major milestone of that effort is officially complete and shipping for Season 4.

We have refactored and multi-threaded the core physics update loop, an internal initiative we call ‘Physics Islands.’ By slicing the physics workload and parallelizing the end of the physics tick, calculations are now distributed cleanly across available CPU threads. While single-car test sessions will feel as crisp as ever, the gains in heavy traffic are massive: in full-field races, crowded multi-car battles, and large AI grids, CPU physics overhead drops by 50% or more across a wide range of hardware.

Beyond immediate frame stability and performance headroom, this architecture shift is a critical building block. It unlocks the technical runway needed for upcoming phases, where we will raise physics tick rates, tighten input sampling, and accelerate force feedback update loops.

Multi-class, multi-pace car

Last quarter, I previewed a major overhaul to our Race Control engine to enable true, real-world Multi-Class Starts. After extensive testing (with a special thanks to everyone who jumped into our ‘iTested’ sessions), that feature is officially soft-launching for Season 4.

Say goodbye to chaotic, stacked-up multi-class grids. The system now deploys dedicated pace cars for each class, maintaining authentic safety margins between fields and throwing independent green flags for every category. This delivers a massive leap in realism and cleaner, fairer turn-one racing across the board.

We’re launching this feature on select tracks to start, headlined by full support in our official IMSA series. With this advancement now complete, the team now has the bandwidth to tackle the next wave of real-world racing procedures advancements and enhancements on our extensive roadmap.

UI

Season 4 is stacked with new features, all powered by our updated Sim UI engine. Retiring our legacy UI architecture has unlocked our development pipeline, letting us deliver long-planned advancements without technical friction holding us back. In this build, you’ll find a seamless blend of everyday racing improvements and innovative features designed to push the sim forward. Here is a look at what’s on offer:

• Pit Summary: In iRacing, a trip down pit lane is almost always critical – whether you are taking fuel and tires, making car adjustments, repairing damage, executing strategy, serving a penalty, or swapping drivers. While we’ve traditionally provided pit-stop-related information through spotter calls and black box overlays, the experience has often been more ambiguous than it should be, leaving drivers with less information than a real-world crew would provide. Season 4 addresses this with an all-new Pit Summary UI. During your stop, you’ll now have full real-time visibility into estimated service durations, damage assessments, active service selections, and a precise visual indicator for your exact pit stall location. Anyone who has ever overshot the final pit stall at Watkins Glen will certainly sympathize.
• Car Damage UI: While we offer spotter-reported damage assessments, it can still be ambiguous just how damaged (or undamaged) your car actually is. In the real world, race teams benefit from sensors, cameras, and performance data to determine whether and where a car is damaged. To help close that information gap, we’ve developed a new visual damage indicator. This opt-in feature applies a color-coded treatment to a graphical representation of your car. To keep things realistic, this indicator provides a fuzzy, practical estimate rather than artificial, pinpoint precision.
• Reference Car UI: Time Trial, Time Attack, and Test Drive are fantastic modes for improving lap times or learning a new track. Chasing your own ghost car or a competitor’s can teach you a lot. We’ve expanded these modes by introducing a new UI directly within the 3D world, attached to the reference car. This display shows live driver inputs, such as braking points, allowing you to analyze their technique and advance your own driving.
• Quick Settings: This new UI replaces the legacy F9 black box, which had become a hodgepodge of various camera, graphics, and input controls. We’ve added additional settings and reorganized the entire interface to make it much easier to use.
• Shifting Feedback: To clear up uncertainty regarding whether a gear shift actually registered, the gear indicator has been enhanced to visually display both successful shifts and mis-shifts. This setting is optional.
• Pinned Mode: You can now pin specific UI elements so they remain visible even when the rest of the HUD is hidden. For example, if you want to keep input telemetry visible while watching a replay without cluttering your screen with the rest of the UI, Pinned Mode allows you to do just that.

VFX

We fully migrated our smoke and particle effects to our modern VFX engine, stepping away from the legacy smoke renderer for good. The result is thicker, far more visually authentic smoke and dirt, complete with dynamic lighting response, accurate visibility occlusion, and realistic physical interaction with wind. Notably (and a personal favorite of mine given my earlier NASCAR ’26 burnout enthusiasm), laying down post-race burnouts is now an absolute blast… just be mindful to do it once incident points are done calculating.

Weather

A couple of seasons back, we noted that we were closely monitoring feedback regarding the rollout and ongoing use of our dynamic weather system, including rain. While we’ve been relatively quiet publicly, internal development and discussions have been anything but. We aren’t ready to make dramatic service-wide changes just yet, but Season 4 introduces a few targeted capabilities to gauge reception and collect more data.

To start, we’re testing weather re-rolls in two distinct ways: per-race re-rolls and per-race-day re-rolls. Additionally, we’re working directly with community managers across a few select series to test forecasts with a higher likelihood of rain.

Looking further ahead, our weather roadmap forecast continues to evolve 😉 The team is hard at work introducing deeper condition variability, more life-like weather patterns, and expanding the overall atmospheric simulation.

Future

Thanks to our incredible sim development team, we have more in the works than ever. I’ll touch on a few notable projects, but this is by no means an exhaustive list, and apologies if I left out something critical to you. I will no doubt touch on more in subsequent updates.

Single Player Career Mode

Career Mode is a project I’ve touched on briefly in each of our recent updates. We were so close to making this post an official release announcement rather than another progress update, but the mode needs just a little more time in the oven. That said, I’m thrilled to share that Career Mode is now officially technology-complete, and our team’s focus has fully shifted to bug squashing, usability testing, and final polish.

That brings us to something we haven’t fully spelled out yet: what exactly is Career Mode in iRacing? Plenty of racing games offer career modes, and each has its own take on the concept. So, what does a single-player iRacing Career Mode look like?

Career Mode redefines the iRacing experience, offering a single-player platform where drivers can follow the path real-world racers take—working their way up from grassroots local racing to the pinnacle of their favorite category.

Initially, Career Mode will launch with a core feature set built around racing, learning, advancement, objectives, leaderboards, realistic progression paths, and an unprecedented amount of included content. Ultimately, the goal is to provide a realistic, engaging experience you can enjoy at your own pace, competing at a level that’s right for you, and have a lot of fun along the way.

What to Expect on Day One

• Massive Scope: Career Mode will debut with seven unique Careers, each offering a full game’s worth of content. Two iRacers pursuing the same end goal—like becoming a top-level GT racer—can take radically different forking routes, competing in different regions of the world before converging on a global scale.
• Zero Extra Cost: Career Mode is included with your standard iRacing subscription, with no additional car or track purchases required for the mode. 
• Content Access: Cars and tracks automatically unlock as you advance through your Career and re-lock upon completing each race week or season. This access is exclusive to this mode and does not transfer to the broader iRacing service.   
• Ladder Design: Our designers had full access to our content library with their designs – their focus: to make the most compelling and authentic career ladders possible.  Making this happen was a crucial decision to eliminate barriers and deliver a complete, deep experience using our multi-decade-spanning content library.
• Success and advancement criteria: Career mode is not structured in the same way as official racing. You advance in Career Mode based on objectives you are given each season by our Career Mode objective system.  Principally, you are expected to achieve a level of performance in standings to meet the criteria for advancement.  If you don’t succeed, you are given additional kicks at the can, but they are limited and you can ultimately get demoted and have to start a career over.  That said, don’t worry if you want a casual experience – difficulty is adjustable.  Additionally, you are given a set number of re-dos each season, but the more you take, the lower your overall leaderboard score.
• Career Length:  Careers are lengthy, as they are designed to parallel the real world.  Race lengths and schedule depth increases the higher you get in competition.  However, this is also adjustable, and customization of schedule length and race length is provided.
• Authentic Foundations: Designed by a core group of sim racers, a former motorsport team manager, internal designers, and real-world professional drivers. 

To set expectations properly, it’s also important to cover what Career Mode isn’t—at least on Day 1. It won’t debut with some common career mode features right out of the gate, such as a driver/owner system, sponsorship management, or team budgets. What we do have is a powerful dynamic foundation packed with new technology, intentional and fun career design, groundbreaking technology to power career variability, focused single-player gameplay with global competition via leaderboards, and a platform built for continuous expansion.

New Careers will launch over time as demand dictates, alongside special one-off Career Events. As with all things iRacing, this is just the beginning—our roadmap includes plenty of additional systems for future updates, including Save Game. We’re extremely proud of this mode and can’t wait for you all to get your racing-glove-clad hands on it.

New Graphics Engine

Our graphics engineers and artists have been hard at work on night lighting for our new renderer. We’ve built a brand-new tooling pipeline for physically based lighting (PBL) from scratch, enabling emissive materials on everything from the iconic string lights around the Nordschleife and glowing palm trees at Sebring to Daytona’s massive standings tower and the radiating garages at Le Mans.

For the first time in iRacing history, a full field of cars can race around a truly physically lit track. This has been a long-standing wish for members and developers alike, and we can’t wait to show it off in all its literal brilliance.

As part of this comprehensive rendering overhaul, we also reworked the physics system that calculates solar track irradiance. This delivers far more accurate track dynamics and temperatures while, in a surprisingly pleasant twist, reducing network traffic sent from the client.

Recognizing that RAM (I don’t mean the truck) has become more expensive than gold, the team has focused heavily on memory optimizations, including the implementation of a full texture-streaming system. This ensures iRacing can be enjoyed both by those who invested in RAM and those who invested in gold… delivering the highest-quality textures possible on your specific hardware.

We’re closer to the finish line than it might seem, and this project will redefine iRacing and sim racing as a whole for years to come. Further, much like the new Sim UI, that ‘finish line’ will only be the beginning, as the new graphics engine is built from the ground up for continued improvement and expansion at a rate not possible with our legacy technology.

Misc Updates

Thanks for sticking with me so far. As you can see, a lot of exciting updates are here, and as always, even more are in the works for the future. Now let’s close this out with our usual list of ongoing unclassified updates. 

• Track Reverb is on the bubble for release. We’re still thoroughly testing its performance impact. We won’t release it until we’re confident it won’t adversely affect performance and framerate. I can say we use it every day, and the Valkyrie, together with Reverb, sounds absolutely amazing.
• We have an all-new, completely rebuilt racing helmet in the works. The project substantially increases fidelity, offering higher 3D complexity and texture resolution. This was almost ready for the build, but we held it back for a bit more final polish. Expect to see it next time.

• While S4 had many “new” tracks (new scans), it didn’t have any new-to-iRacing tracks. Season 1 will have us returning to form, with the addition of multiple all-new tracks.
• The Circuit Bugatti scan was a huge success, not thwarted by 3,000 parked vehicles and TV haulers like last time. Modeling on the drivable surface is even complete.
• Circuit Paul Ricard is well underway.
• We’re turning laps at Winchester Speedway 
• Our scan and photo teams have visits scheduled for Circuit Paul Armagnac in France…
• …and we are currently booking our next scan in Spain, at Circuit Ricardo Tormo.
• We are working to revisit some previously announced track projects that haven’t moved forward as quickly as we’d like.
• Improvements to netcode related to both car-to-car AND car-to-world collision are ongoing.
• iRacing Companion App 3.0 is live on iOS and Android. A substantial core architecture overhaul now seamlessly syncs your favorites, friends, and social connections directly with the desktop client in real time.

On the telemetry and feature front, the update brings Weather V2 integration, season scheduling, and detailed race details. The release is rounded out with a guided reminder wizard, upgraded search filters, redesigned Event Results, and localization support for eight languages.

Writing these updates is always a welcome chance to step back and reflect on the sheer scope of what our team is building. Looking across the studio, every effort aligns with our core mission: enhancing your daily racing experience, delivering absolute realism, growing the sim motorsports footprint across the world, supporting our existing communities, and future-proofing our simulation architecture to stay at the cutting edge of technology. It drives our work across UI refinements, ongoing tire model development, the new renderer, audio overhauls, and much more.

None of this happens without you. Thank you for fueling these advancements with your passion, participation, and dedicated membership. We love what we build every day at iRacing, and we’re privileged to serve such a knowledgeable community of sim racers. I can’t wait to pull back the curtain on some of our big projects even further next time.

Until then, we’ll see you out there for Season 4.

See you at the finish line,

Greg

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