Build your own telemetry

Click MATH CHANNELS in the top-left of the Telemetry Graphs tab. The panel opens on the right side.

Let's build a net pedal input channel — positive when you're on the throttle, negative when braking.

1. 01Click + New at the top of the channel list.
2. 02In the Formula field, type:

   throttle - brake

   Channel names highlight in teal as you type. A typo shows Unknown channel: ‘thottle’. Did you mean ‘throttle’?
3. 03Fill in metadata:
   • Name: net_pedal — lowercase, no spaces. Used to reference this channel from other formulas.
   • Unit: % — free text label on the graph.
   • Color: click the swatch and pick something distinct.
4. 04Click Save. A new graph appears at the bottom of the stack — drive a lap and the trace fills in.

A formula is a single expression — no variables, statements, or loops. The grammar is small enough to fit on this page.

a + b      addition
a - b      subtraction
a * b      multiplication
a / b      division (returns 0 if b is 0)
a % b      remainder
a // b     floor division
a ** b     power, e.g. 2 ** 3 == 8
-a         negation

a > b      a < b      a >= b      a <= b
a == b     a != b

cond1 and cond2
cond1 or cond2
not cond

value_if_true if condition else value_if_false

The raw telemetry channels you can reference inside a formula. Categories are for navigation; in formulas you just write the name.

Fourteen channels ship with the app. They're useful on their own and double as worked examples — duplicate any of them to see how the formula is built.

avg(tyre_temp_fl, tyre_temp_fr)

avg(tyre_temp_rl, tyre_temp_rr)

front_temp_avg - rear_temp_avg

avg(tyre_temp_fl, tyre_temp_fr, tyre_temp_rl, tyre_temp_rr)

max(max(tyre_temp_fl, tyre_temp_fr),
    max(tyre_temp_rl, tyre_temp_rr)) -
min(min(tyre_temp_fl, tyre_temp_fr),
    min(tyre_temp_rl, tyre_temp_rr))

1 if brake > 5 and abs(steer_deg) > 15 else 0

clamp(rate(throttle), -500, 500)

clamp(rate(brake), -500, 500)

abs(delta(throttle))

rolling_avg(throttle_jitter, 20)

rate(speed) / 3.6

rolling_max(brake, 100)

lap_start(fuel_l) - fuel_l

Five extra formulas you can paste in. Each one is a single math channel.

1 if throttle < 5 and brake < 5 else 0

1 if throttle > 5 and brake > 5 else 0

avg(tyre_pressure_fl, tyre_pressure_fr) -
avg(tyre_pressure_rl, tyre_pressure_rr)

rolling_avg(abs(delta(steer_deg)), 30)

max(max(tyre_temp_fl, tyre_temp_fr),
    max(tyre_temp_rl, tyre_temp_rr))

• —Stateful function args must be a bare channel name. rate(speed) works; rate(speed * 2) saves cleanly but reads 0 forever, which is harder to debug than an error.
• —Division by zero, NaN, and infinity are silently coerced to safe values (0 or ±1×10⁹). The graph won't blow up, but a formula producing junk also won't shout about it. Sanity- check new formulas during a real session.
• —Errors at save time vs runtime. Syntax errors and unknown channel names show inline in the editor when you save. Errors that only happen during evaluation (a referenced channel disappears later) cause the channel to read 0 silently.
• —Built-in presets can't be edited or deleted. Click duplicate on a preset row to get a copy you can change.
• —Heavy rolling windows cost memory. Each channel keeps a ring buffer; a window of 20 (default) is cheap. 5000 across a dozen channels is not. If the eval-time number in the status bar climbs, that's the first place to look.
• —Channel name validation is helpful. Save a formula with a typo and the editor suggests the closest match: Unknown channel: ‘thottle’. Did you mean ‘throttle’?
• —Persistence. User-made channels are stored in math_channels.json in the S1napse config directory. Copy that file between machines or version it.

• —Telemetry Graphs — the tab that hosts the math channels panel.
• —Lap Analysis — math channels also show up here when you replay a completed lap.