Reference dimensions and placements commonly used in the U.S. for ARA, SCCA, and NASA. Always verify against current series rules & event supplemental regulations.
ARA publishes an official Visual Package / Vehicle Identification Standard that specifies door number placards, windshield banners, and other decals. Placements are diagrammed and may be adjusted slightly for body shape.
| Element | What to prepare | Notes & Source |
|---|---|---|
| Door number placards | Use official ARA template (left & right). Include forward-facing “notch”, black number field, white sponsor band. | Follow ARA brand standards and placement diagram. ARA Visual Package |
| Windshield banner | Full‑width visor banner per template. | See ARA placement guide. Source |
| Rear windshield decal | Prepare ARA‑spec rear glass decal. | New for 2025; issued at Tech. Source |
| Driver/Co‑driver names | Names + national flags on quarter windows. | Per ARA visual standards. Branding & Logo |
Tip: keep the current ARA PDF/template on file so you can cut correct placards without re‑measuring each job.
The SCCA General Competition Rules (GCR) and program pages define required decals and numbers. Solo/TT also specify number & class visibility. Sponsor decals are required at National events.
| Use | Typical size / rule | Notes & Source |
|---|---|---|
| National sponsor decals | Required on each side and front; upright & prominent. | SCCA Vehicle Identification |
| Solo (Rule 3.7) car numbers | ≥ 6" high, ≥ 3/4" stroke, high contrast; class letters on both sides. | SCCA Solo reminder |
| General Road Racing rules | See current GCR for signage/ID & any series‑specific requirements. | 2025 SCCA GCR (PDF) • Cars & Rules hub |
NASA uses the Club Codes & Regulations (CCR) plus series‑specific rules. Sizes below come from 2025 series rulebooks.
| Series | Must‑have decals / IDs | Explicit sizes from rules | Source |
|---|---|---|---|
| Spec E30 | Side, hood/front, and rear numbers; “SE30/Spec E30” class ID; driver last name. | Side numbers ≥ 12" high (stroke 1.5–3"). Hood/rear numbers ≥ 5". Class ID letters/numbers ≥ 3" with ≥ 0.5" stroke. Driver name ≈ 3" on windows + lower passenger windshield. | 2025 Spec E30 Rules (PDF) |
| Spec3 | Series/NASA decals (as required). Class ID near side numbers. Driver last name on windows + windshield. | Class “SPEC3” ≥ 3" tall. Driver last name 3" tall. | 2025 Spec3 Rules (PDF) |
| 944 Spec | Required sponsor & series decals: Hoosier, HAWK, 944 SPEC, NASA (plus any CCR‑required). | Permanent affixing required; sizes/locations per series & CCR (check event supps). | 2025 944 Spec Rules (PDF) |
Browse all NASA series rules here: NASA Rules Portal.
| Position | Baseline cut size | Why this works |
|---|---|---|
| Door numbers (each side) | 10" height | Common club‑racing visibility; aligns with many SCCA/NASA kits. Confirm series rules if larger (e.g., NASA Spec E30 uses 12" min). |
| Hood/front & rear numbers | 8" height | Widely used; ensure contrast and readable stroke. Some series specify 5" minimum for hood/rear. |
| Class letters | 4" height | Matches many kit practices; check series appendix for stroke width. |
| Driver name (windows) | 2–3" height | ARA/SCCA often use ~2"; NASA series frequently call for 3". |
| Windshield strip/banner | Top 4" band | Reserved area is common in rally programs; adhere to event rules regarding sponsor text. |
These are pragmatic defaults for quoting and pre‑cut kits. Always confirm the customer’s sanctioning body, class, and event supplemental regulations.