Division Guide
Super Stock division
Tune the larger sit-up kit car as a complete system, balancing driver fit, legal weight, steering precision, loaded alignment, and aerodynamic presentation.
THE CLASS
More room and mass create more setup choices.
Super Stock is a larger, more streamlined sit-up kit car for bigger or more experienced racers. ISBD's current window is effectively ages 9 through 18 with a 238-240 pound combined weight. NDR currently opens Super Stock from age 7 until the 22nd birthday and uses a 240-pound Z-Glas maximum.
The shell does not turn Super Stock into a custom-body class. Official construction geometry, hardware, axle work, wheel procedures, and weight attachment still control.
SETUP PRIORITIES
Build driver fit and chassis geometry together.
FIT
Compact and repeatable
Keep the racer comfortable enough to hold head, shoulders, hands, and hips still while retaining clear sight, steering reach, and brake control.
LOAD
Legal distribution
ISBD permits up to a 15-pound nose or tail differential. NDR's live 2025 update lists a 15-pound tail differential for Super Stock.
ROLL
Loaded spindle check
The heavier complete system flexes axles. Measure at representative race load after triangulation and crossbind.
AIR
Hold the posture
A lower-looking driver position is only useful if it remains legal, safe, visible, and stable for the entire run.
TRACK DEVELOPMENT
Build a data set, not a collection of hunches.
- Start from a fully inspected baseline with recorded geometry and scales.
- Use multiple paired runs for each change and record lane, wheel bank, weather, driver note, and elapsed time.
- Recheck alignment after transport, hard braking, or a rough road course.
- Practice holding the steering neutral instead of chasing the lane.
- Prepare for wheel and lane swaps so performance does not depend on one lucky wheel location.
The same car can race under different sanctioning bodies, but the setup limits do not travel with it. Reinspect against the event's NDR or ISBD documents.
SOURCES & FURTHER READING
Check the primary material.
- ISBD race divisions and build plans Official division descriptions, age bands, weights, plans, and Legacy information.
- ISBD Rule Book - linked for the 2026 World Championship Official PDF currently linked from Race Week resources; the file itself says revised June 2025.
- NDR divisions and program overview Official NDR descriptions for Stock, Super Stock, Masters, Roundbottom, and Legacy.
- National Derby Rallies rules hub Official NDR landing page, 2025 tail-weight update, rule books, and inspection links.
- Zero Error forum archive: Progressive wheel swap Historical explanation of why lane and wheel swaps reduce wheel and lane advantage.