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NO PREP SERIES RULES

OFFICIAL RULES

NHRDA No Prep Series Rules

The official NHRDA No Prep Race Series Rulebook (PDF) is the single authoritative source for all rules. It covers Average Joe (drop-in turbo) and Blue Collar (S300 / S400 / Compound). The Blue Collar rules are adjustments to the Average Joe class to allow larger singles and compounds — everything outside the turbo sizing section is shared. Run What You Brung is new and is not yet in the published rulebook; its final rule sheet and safety requirements are published per event.

Idle / Launch RPM Rule NEW

At the starting line, the truck must be in Drive and idling at no more than 800 RPM prior to launch. Tech may verify by sound and/or tach. Failure to comply may result in disqualification.

Class Comparison — Turbo Allowances

Platform Average Joe
Drop-In Turbo Class
 Blue Collar
S300 / S400 / Compound Class
 Run What You Brung
Unlimited Open Class
6.4L Power Stroke Stock-size billet wheels only May run compounds OR S300/S400 within sizing —
Common Rail (Duramax, 6.7 PS, 5.9 & 6.7 Cummins) 64mm drop-in — —
6.0L Power Stroke & 12V/P-Pump Cummins Up to 68mm drop-in — —
7.3L Power Stroke & VP44 Cummins Up to 68mm drop-in — —
S300 / S400 — 72mm max compressor wheel —
Compounds — 64mm HP with 76mm LP —
Factory VGT w/ Compounds — Must retain the factory VGT —
All diesels — — No size restrictions — run what you brung

Average Joe Class Notes

  • Single turbo only
  • VGT-equipped trucks must retain a VGT turbo
  • No compounds (unless factory), no T4 swap kits, no S300 or S400 swap kits
  • Turbo must be a readily available drop-in style purchasable via online retailer — no custom one-off turbos
  • MAP groove must be smaller than 0.200″
  • No removable plugs or bushings — all welded
Average Joe Details

Blue Collar Class Notes

  • Fire jacket required in addition to standard safety gear
  • Factory VGT trucks running compounds must retain the factory VGT on the manifold — applies to 6.0L PS, 6.7L PS, VGT Cummins, and VGT Duramax
  • S467 Cummins is welcome
Blue Collar Details

Run What You Brung Class Notes

  • Targeting the 3,000+ hp race truck crowd
  • Flashlight start, 1/8 mile, no prep surface, single elimination
  • Final rule sheet and safety requirements published per event
Run What You Brung Details

Shared Rules (Apply to Both Classes)

Vehicle Eligibility & Weight

  • Diesel vans, trucks, and Excursions only
  • Must be a production truck that came from the factory with a diesel engine
  • No cars or car-based chassis conversions
  • Minimum race weight: 7,000 lbs
  • Up to 1,500 lbs of ballast — must be securely bolted inside the bed at the very front

Fuel System & Drivetrain

  • Single high-pressure injection pump only
  • No limitations on lift pump systems
  • 2WD only. 4WD trucks must remove the front driveshaft — no exceptions

Chassis & Suspension

  • Full factory frame required — no back-half trucks
  • No aftermarket rear 4-link systems (factory 4-link OK)
  • No rear coil-over conversions
  • Front 4-link and coil-over kits permitted
  • Allowed: modified stock suspension, lift/lowering kits, CalTracs, rear traction bars, spring/shock changes
  • Modified radius arm front suspensions allowed on originally equipped trucks
  • Not allowed: rear coil-overs, aftermarket rear 4-link, back-half conversions

Transmissions & Tires

  • Trans swap OK
  • Manual valve body OK
  • No trans brake, no bump box, no line-lock
  • Street tires only — minimum 400 treadwear
  • No slicks, no drag radials. M/T, R/T, H/T, A/T all fine if 400+ TW

Power Adders & Electronics

  • No water injection
  • No methanol injection
  • No propane injection
  • No nitrous — fuel only
  • No aftermarket water-to-air intercoolers (6.7 Power Stroke exception: must retain drop-in OEM-location parts)
  • Factory ECU required — OEM ECU swaps allowed. No restrictions on tunes/tuners
  • No standalone ECUs, no aftermarket traction control. Foot brake racing only

Race Format

  • 1/8 mile, instant green (flashlight start may be used)
  • Non-boosted launches — leave from idle
  • Cross center — you lose
  • Leave early — you lose
  • Single burnout — 5 seconds maximum
  • First across the finish wins
  • Single elimination — no buy-backs
  • No time slips issued or displayed
  • No prep surface — racing held after the main event
  • Hot laps will happen — street trucks should be able to hot lap all day

Protective Equipment (Both Classes)

  • Helmet
  • Long-sleeve shirt
  • Pants (jeans)
  • Closed-toe shoes
Blue Collar class: a fire jacket is also required in addition to the shared protective equipment list.

Right to Protest

$500 protest fee. If the protested truck is found illegal, it is disqualified and the protest money is returned. If the truck is found legal, the protested competitor receives the $500.

Rules Interpretation Disclaimer

The Blue Collar S300/S400/Compound rules are the only adjustments from the original Average Joe class design to allow the S300/S400/Compound crowd to join. All rules from the original Average Joe class apply unless specified otherwise in the S300/S400/Compounds section. This aligns with standard practices used by professional motorsports sanctioning bodies including SCCA, NASA, NHRA, NHRDA, and FIA. For additional clarification regarding the rules set forth for this class, contact your preferred NHRDA point of contact.

Required for all competitors: Helmet, long sleeve shirt, jeans, closed-toe shoes. Blue Collar racers must also have a fire jacket. Make sure you follow these rules.

Download Full Rules PDFs

NHRDA No Prep Race Series Rulebook (Official)
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