Roll centre — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/roll-centre/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
Catalog version: 2026-10-20

Sizes: see table below
- The roll centre is the point about which the body rolls on its suspension; on a double-wishbone layout it is found by extending the arms to their instant centre and drawing lines to the contact patches (Formula1-Dictionary; Suspension Secrets).
- Lower roll centres give more roll; as the suspension compresses the roll centre rises and the roll moment shrinks (Formula1-Dictionary). On a solid axle with a panhard bar, the roll centre is the mid-point of the bar (NC4x4).
- On RC cars, upper shock-tower link holes lower the roll centre and add corner-entry steering; lower holes raise it for high grip (Tekno).
- The file is a reference example built by Xem Studio from the numbers above (Reference 1/10 touring car: wheelbase 260 mm (AARCMCC ISTC 250-270), track 190 mm (EFRA width without body), 50 mm = EFRA rim limit.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

parameter  value or range  source
Panhard axle roll centre  mid-point of panhard rod  NC4x4 forum
Roll axis nose-down  tends to oversteer; nose-up tends to understeer  Formula1-Dictionary
RC upper tower holes  lower RC, more entry steering  Tekno setup guide

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Formula1-Dictionary: Roll center — web — Publisher's page; dimensions are facts — https://formula1-dictionary.net/roll_center.html
- Suspension Secrets: Suspension geometry explained — web — Publisher's page; dimensions are facts — https://suspensionsecrets.co.uk/suspension-geometry-explained
- NC4x4 forum: General 4 Link Suspension Design Information — web — Publisher's page; dimensions are facts — https://nc4x4.com/forum/threads/general-4-link-suspension-design-information.72892/
- Tekno RC: Tekno RC Setup Guide — web — Publisher's page; dimensions are facts — https://teknoforums.com/misc/Tekno-RC-Setup-Guide.pdf
- CompetitionX: RC Quick Setup Guide — web — Publisher's page; dimensions are facts — https://www.competitionx.com/?p=129

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/roll-centre/index.json
API: https://xemstudio.com/api/geometry?object=roll-centre