iRacing companion apps and tools

Four apps cover what almost every iRacer runs: Garage 61 (telemetry), CrewChief (spotter and race engineer), RaceLab (on-screen overlays), and Trading Paints (custom liveries). Three of the four are free or have a usable free tier. Start there before you clutter your PC with anything else.

App	Does what	Free or paid
Trading Paints	Auto-downloads other racers’ custom liveries into your session	Free; Pro $23.99/yr
CrewChief	Adds a separate spotter voice + race engineer	Free (donation-supported)
Garage 61	Telemetry comparison + setup browser	Free tier; Pro from €5/mo ($6)
RaceLab	Overlays: relative, standings, fuel, input trace, delta	Free tier; Pro ~€5/mo

Telemetry and finding lap time

Garage 61’s free tier already does the job most drivers need: record your own laps, then overlay them on a faster reference to see exactly where you’re losing time on the brakes, the throttle, or the line. Pro starts at about €5/month (~$6) and unlocks setup filtering, viewing telemetry on other drivers’ laps, and longer data storage. If you publish your data publicly you keep most features free; you mostly pay to keep your telemetry private.

For deeper analysis, VRS (Virtual Racing School) sells data packs and coaching, and ships a free rookie MX-5 data pack to start with. Its core data packs cover GT3 and other road series; NASCAR and oval packs come from the Altus Engineering partnership, and Apex Racing Academy data packs are viewable through the VRS integration. Beyond that sit full pro tools like MoTeC and ATLAS, which you only need if you’re chasing channel-level analysis Garage 61 can’t show.

One hard limit applies to every tool here: the iRacing telemetry API exposes only surface tire temps, not core temp or true real-time wear, delays your own car’s live data by about 20 minutes during races, and gives only relative positions of other cars rather than precise absolute positioning. No third-party overlay can show true tire wear or perfectly accurate gaps to other cars. If an app claims it does, it’s estimating.

Spotter and race engineer: CrewChief

CrewChief is 100% free and runs on iRacing, ACC, AMS2, RaceRoom, and F1. Its edge over the built-in spotter is two independent voices: an engineer calling fuel, lap times, and strategy, and a spotter calling car left, car right, and clear, with the spotter given priority so a proximity call never gets buried under a lap-time readout. The spotter triggers are configurable by distance.

It isn’t faster than iRacing’s native spotter, but it adds proximity warnings, incident-ahead alerts, and live fuel math the stock spotter doesn’t give you. Learn the fuel commands and the “how’s my pace” query and you’ve covered most of what people leave unused.

Overlays

RaceLab gives you a relative box, standings, fuel calculator, input traces, track map, and delta on a free tier, with Pro around €5/month. The catch most people hit: the brake/throttle/delta graph trace is Pro-only on both RaceLab and iOverlay. If that graph is all you want, SimHub and Kapps both include it for free.

Kapps unlocks via a one-time Twitch sub, so it’s effectively near-free, but development is suspended, so don’t expect new features. iOverlay is RaceLab’s closest competitor and also gates the graph behind a paid tier.

A common gotcha: don’t run an overlay’s auto-fuel calculation and iRacing’s built-in fuel calc at once. They read the same data and people report RaceLab’s numbers looking wrong when both are fighting. Pick one. iRacing’s own UI keeps absorbing overlay features (in-sim relative, black box), so check what you already have before paying.

Liveries: Trading Paints

The free Trading Paints desktop app auto-downloads other racers’ custom paints into your session. Without it, everyone shows up in default liveries. Pro ($23.99/yr) adds the Paint Builder for designing your own car, plus custom number styles and night-race paints. Many racers call it the single essential third-party tool.

Hardware glue: SimHub

SimHub’s core is free, and it matters the moment you add hardware beyond a wheel and pedals: a wheel display, a button-box dash, bass shakers or haptics, or DIY Arduino gear. It drives dashboards, telemetry overlays, and transducer effects. If you have no extra hardware and only want a relative or standings box, you don’t need it, and that’s the source of most of the “is SimHub really that important” confusion.

Tracking your schedule and time-to-green

An iRacing season runs 12 race weeks plus Week 13, the off-week. The official site has the schedule but it’s clunky for planning which series you’ll run and when. Every app above lives on your PC mid-race; Startlight ($9.99 iOS app, Home Screen widget, and Apple Watch app) is the one that lives on your phone and wrist, showing what session is running now, what’s next, and time-to-green when you’re away from the rig.