RBR

Setup Studio

i
Test Version — feedback welcome below
Hover any i icon for information
Profile i
3D Model i
Load a car to see its 3D model
All Settings i

No car loaded

Select a car in the top bar to load its default setup, or import an RBR setup .lsp.

Setup Guide & Reference i
What is a Setup?

A setup is a set of mechanical adjustments that changes how the car grips, rotates, rides bumps, and reacts to your inputs. There is no single "best" setup for all stages: every change is a tradeoff.

  • Mechanical grip: how well tyres stay in contact with the surface, especially on rough or low-grip roads.
  • Platform control: how much the body rolls, pitches, and dives under braking, throttle, and cornering.
  • Balance: whether the car tends toward understeer (front pushes) or oversteer (rear rotates).

Setup Studio uses the same RSF/NGP parameter model and file format (.lsp) used in RBR, so edits here map to in-game behavior.

Tuning Workflow

Use this repeatable loop to avoid random changes:

  1. Select car and surface first so defaults and valid ranges are correct.
  2. Run a baseline on a short test section and write down one main symptom.
  3. Change one item (or one mirrored pair with Symmetrical Editing) per test cycle.
  4. Re-test the same section at similar pace and compare behavior, not lap time first.
  5. Keep what clearly helps; undo changes that do not.
  6. Fix in priority order: braking stability, entry behavior, mid-corner balance, then exit traction.
  7. Only fine-tune after stability (pressure, gearing, small geometry/damper steps).
  8. Export the setup when the car is predictable and confidence is high.
Surface Philosophy

Gravel / Rough Roads

Goal: keep tyres in contact over bumps and loose surface.

  • Usually softer springs and softer low-speed bump than tarmac.
  • Usually lower tyre pressure for compliance and contact patch support.
  • Use enough diff lock for drive, but not so much that the car refuses to rotate.

Tarmac

Goal: platform control and precise response on higher grip.

  • Usually stiffer springs/damping than gravel for cleaner transitions.
  • Usually higher tyre pressure for sharper response and support.
  • Geometry and diff-map changes are more immediately felt.

Snow / Ice

Goal: smooth, predictable weight transfer on very low grip.

  • Avoid extreme values; smooth behavior beats aggressive response.
  • Too much diff lock can cause abrupt push/snap behavior.
  • Bias toward compliance and stability over sharp rotation.
Gearing

RBR uses a drop gear index (preset ratio package), not independent editable gear pairs.

  • Lower index (shorter): stronger acceleration, lower top speed.
  • Higher index (longer): lower acceleration, higher top speed.
  • Pick the lowest ratio set that still avoids limiter on longest fast sections.
Tyres and Pressure

Tyre pressure is one of the highest-impact quick adjustments.

  • Increase pressure: faster response, stiffer carcass, less compliance on rough surfaces.
  • Decrease pressure: more compliance/contact, but slower response and more carcass movement.
  • Keep left/right close unless you are correcting a specific side behavior.
  • Use small steps and re-test quickly; pressure effects are easy to overdo.
Brakes and Bias

Front and rear brake pressure are independent. Their ratio defines effective brake bias.

  • More front bias: usually safer/stabler braking, but less entry rotation and possible front lock on loose surface.
  • More rear bias: usually more entry rotation, but higher rear-lock and spin risk.
  • Handbrake pressure up: quicker rear lock for pivots; down: smoother, easier modulation.

Use Live Readouts to confirm front/rear bias after each pressure change.

Differentials: Overview

Differentials control how strongly wheels/axles are coupled under power and braking. More lock generally improves traction but can reduce rotation freedom.

  • Front diff: higher lock usually adds drive stability but can increase understeer.
  • Rear diff: higher lock usually improves exit drive but can make rear behavior sharper.
  • Center diff (AWD): higher lock increases front/rear coupling and stability, lower lock frees rotation.

Preload/max torque sets the locking envelope. Maps then request lock within that envelope.

Differential Maps

Maps define requested lock versus driver input and speed.

Throttle Map (Power Side)

  • Increase lock values: more coupled axle behavior under power (often more traction, less free rotation).
  • Decrease lock values: freer rotation on throttle (often less push, but easier wheelspin).

Brake Map (Coast Side)

  • Increase lock values: stronger coupling on decel/trail-brake (can calm or destabilize depending on axle and balance).
  • Decrease lock values: freer decel rotation and lighter entry behavior.

Speed Map (Active Diffs)

Scales lock with vehicle speed. Useful for making low-speed and high-speed behavior different.

Mechanical vs Active

For many mechanical diffs, only the first row is effective; extra rows and speed scaling are ignored. For active diffs, full maps are used.

Special Controls

  • Left-Foot Threshold: brake level that activates alternate center map while throttle is still applied.
  • Center HB Release: handbrake input level where center coupling releases for tighter hairpin rotation.
Springs and Helper Springs

Main Springs

  • Rate up: less roll/pitch, faster response, less rough-surface compliance.
  • Rate down: more compliance/grip on rough roads, more body motion.
  • Length/perch changes: alter preload and often ride height; always verify in Live Readouts.

Helper Springs

  • Helper length up: helper stays engaged through more travel (wider dual-rate zone).
  • Helper rate up: firmer initial support before main-spring-only behavior.

Note: Helper minimum length is computed by the plugin at stage start (40% of helper free length).

Dampers

Dampers control suspension speed; springs control suspension position/travel.

Low-Speed Bump (Compression)

  • Increase: more platform support (less dive/roll), but harsher on rough inputs.
  • Decrease: more compliance, but softer platform control.

Low-Speed Rebound (Extension)

  • Increase: slower extension/weight return, more settled transitions, risk of grip loss or "packing" on repeated bumps.
  • Decrease: faster wheel return and response, can feel less controlled if too low.

High-Speed (Fast) Bump + Threshold

  • Fast bump up: more resistance on sharp impacts/landings.
  • Fast bump down: easier blow-off over sharp hits, less chassis shock.
  • Threshold up: fast circuit engages on larger events only.
  • Threshold down: fast circuit engages sooner on smaller bumps.
Bump Stops

Bump stops are end-of-travel supports that prevent hard bottoming and shape behavior near full compression.

  • Stiffness up: stronger support near travel limit, more harshness risk.
  • Bump damping up: slower entry into bump-stop zone on heavy compressions.
  • Rebound damping up: slower release from deep compression after big hits.
  • Progressive bump stops: softer initial contact, rapidly increasing support deeper in travel.
Geometry

Toe, camber, caster, and ride height are calculated from suspension hardpoints in RBR. You do not type toe/camber directly here; you change geometry controls and verify outputs in Live Readouts.

Toe

  • Toe-out generally sharpens response but can reduce straight-line stability.
  • Toe-in generally increases stability but can reduce initial rotation.

Camber

  • More negative camber usually helps loaded-corner grip, but too much can reduce braking/straight-line contact.

Caster (Front)

  • More caster usually increases self-aligning torque and dynamic camber while steering.

Main Geometry Controls

  • Top Mount Slot: discrete hardpoint position changes.
  • Steering Rod Length: strong effect on toe and steering behavior.
  • Strut Platform Height: ride height/preload influence.
  • Wheel Axis Inclination: camber gain and steering-axis behavior influence.
Roll Bars and Steering Lock

Anti-Roll Bars

  • Front bar stiffer: usually more understeer in steady-state cornering.
  • Rear bar stiffer: usually more rotation, with higher rear breakaway risk.
  • Treat front/rear bar split as a mid-corner balance tool.

Steering Lock

  • Lock up: easier tight hairpins, more sensitivity at high speed.
  • Lock down: calmer high-speed steering, larger minimum turning radius.
Troubleshooting Flowchart

Use this order: confirm symptom -> make one targeted change -> re-test same section.

Entry Understeer (car does not rotate on turn-in)

  1. Move brake bias slightly rearward (or reduce extreme front bias).
  2. Reduce front coast/brake-side diff lock if high.
  3. Soften overly stiff front ARB/spring settings.
  4. Review front toe behavior in Live Readouts.

Entry Oversteer (rear unstable under braking)

  1. Move brake bias slightly forward (or reduce extreme rear bias).
  2. Reduce rear coast/brake-side diff lock if high.
  3. Soften overly stiff rear ARB/spring/rebound settings.
  4. Add rear stability via geometry (often more rear toe-in).

Mid-Corner Push or Snap

  1. Adjust ARB split first (front softer/rear stiffer for more rotation, opposite for more stability).
  2. Then adjust spring split with small steps.
  3. Then refine diff preload/lock behavior for the same phase.

Poor Exit Traction / Exit Oversteer

  1. For low drive: increase relevant diff preload/lock and check rear compliance/pressure.
  2. For power snap: reduce rear diff lock/preload and soften aggressive rear balance.
  3. On AWD, use center coupling to balance front/rear drive share.

Bottoming / Harsh Impacts

  1. Increase travel margin (ride height/perch/spring length as appropriate).
  2. Tune fast bump and bump-stop support for heavy hits.
  3. Use progressive bump stops where supported.

Rule: if one fix helps one phase but hurts another, reduce the step size and split the correction between complementary controls.

Technical Reference

Implementation-level notes used by Setup Studio and aligned with RSF/NGP conventions.

Units and Conventions

  • Internal math uses Float32 to match RBR precision behavior.
  • Angles stored in radians, displayed in degrees.
  • Lengths stored in meters, displayed in millimeters.
  • Pressures stored in Pa, displayed in kPa.
  • Damping stored in N/(m/s), displayed in kN/(m/s).
  • Spring rates stored in N/m, displayed in kN/m.

Differential System

  • Diff controls include preload/max torque plus throttle/brake/speed mapping.
  • Active diffs use full mapping logic; many mechanical diffs effectively use first-row lock behavior only.
  • Left-foot and handbrake center controls alter center-diff behavior by input thresholds.

Geometry System

  • Toe/camber/caster/ride-height readouts are solver outputs from hardpoint geometry.
  • Adjustable hardpoint controls: top mount slot, steering rod length, strut platform height, wheel axis inclination.
  • Sign convention in this app: positive toe = toe-in, negative camber = top inward.

Suspension + Brakes

  • Each corner uses main + helper spring plus low/high-speed damper behavior.
  • Bump-stop stiffness/damping are separate end-of-travel controls.
  • Brake bias is derived from independent front/rear pressure values.

Setup File Format

  • .lsp files are text-based section/value data.
  • Parameters are addressed by paths (for example SpringDamperLF.SpringStiffness).
  • Symmetrical editing mirrors LF<->RF and LR<->RR changes.
Feedback i