SimHub with iRacing

Last updated 4 August 2026 · SimHub 9.11.22

iRacing publishes telemetry through shared memory, and SimHub reads it directly — but only after iRacing has been told to publish it at all. The setting is irsdkEnableMem=1 in iRacing's app.ini, and without it no external tool sees anything, no matter how it is configured. Once enabled, iRacing is one of the richest telemetry sources SimHub supports, with full data, effects and motion, plus a large ecosystem of iRacing-specific dashboards and plugins.

iRacing is the best-supported sim in SimHub's ecosystem by some distance, and also the one with a single mandatory setting that stops everything if it is missing.

How it works

Shared memory. iRacing publishes telemetry into a memory-mapped region and SimHub reads it directly — fast, low overhead, and local to the machine, which is why iRacing is PC only.

Because it is shared memory rather than UDP, any number of applications can read it at once. SimHub, CrewChief, a lap timer and a coaching tool can all run simultaneously with no conflict at all — which is not true of the UDP games.

The one thing iRacing needs that other shared-memory games do not. The telemetry interface is not published by default. irsdkEnableMem=1 has to be set before anything can read it.

Setting it up

Set irsdkEnableMem=1
In iRacing's app.ini, under the [Misc] section. Add the line if it is not there. This is the step that matters — without it, no external telemetry tool works with iRacing at all.
Restart iRacing
The setting is read at startup. Editing it mid-session changes nothing.
Enable iRacing in SimHub
SimHub only watches games you have ticked.
Match administrator rights
If iRacing or its launcher runs elevated, SimHub must too — Windows will not let a normal process read an elevated one's memory, and it fails silently.
Go on track and check
Live values should appear on SimHub's home screen. Practice alone is enough; you do not need a session with other cars.

iRacing-specific gotchas

irsdkEnableMem=1 can be reset. A clean install, a settings reset, or occasionally a service update can put app.ini back. If telemetry stops for no reason, check this line first.
Elevation. iRacing is not normally elevated, but launchers and overlays sometimes are. If SimHub sees nothing and the setting is right, this is next.
Telemetry exists in replays too, which is useful — you can configure LEDs and shakers against a saved replay rather than driving.
Some values are session-dependent. Fuel and tyre data behave differently in a race than in an open practice session, which can make an effect look broken when it is simply idle.

What works well here

iRacing provides a rich telemetry set, so most ShakeIt effects have real data behind them. It is one of the sims where a haptics setup pays back the effort of tuning it.

The one thing worth knowing: iRacing's dashboard and plugin ecosystem is the largest of any sim. Several plugins add computed properties iRacing does not provide directly — PostItNoteRacing is the widely used one — and a number of dashboards are built assuming those properties exist. If a downloaded iRacing dashboard shows empty fields, it is almost certainly waiting on a plugin.

Common questions

What is irsdkEnableMem=1?

A setting in iRacing's app.ini, under [Misc], that makes iRacing publish its telemetry interface. Without it, no external application — SimHub, CrewChief, or anything else — can read iRacing telemetry at all. Restart iRacing after changing it.

Where is iRacing's app.ini?

In your iRacing documents folder, alongside your other iRacing configuration. Add irsdkEnableMem=1 under the [Misc] section if it is not already there.

Can I run SimHub and CrewChief with iRacing at the same time?

Yes, with no configuration at all. iRacing uses shared memory, which any number of applications can read simultaneously. The one-app-at-a-time problem only affects UDP games such as Forza and the F1 series.

Why does SimHub see nothing in iRacing?

Almost always irsdkEnableMem=1 missing from app.ini, or not having restarted iRacing after adding it. Second most likely is an administrator-rights mismatch, where an elevated launcher means SimHub cannot read the memory region.

Does SimHub work with iRacing replays?

Yes, and it is a good way to tune haptics and LEDs — you can configure against the same corner repeatedly rather than driving it each time.

Why is my iRacing dashboard showing empty fields?

It probably depends on a plugin that supplies computed properties iRacing does not provide directly. PostItNoteRacing is the common one. Install the plugin, restart SimHub and accept the enable prompt.

Sources

SimHub is developed independently by Wotever and is not affiliated with oesimracing. This page was checked against SimHub 9.11.22 on 4 August 2026; where the interface has moved on since, the version stamp tells you how far. More on what SimHub is and what it costs.