Not legal1 part
Bolts, nuts and washers may not be substituted with titanium unless originally equipped. Locking mechanisms are allowed. J.7
- Titanium fasteners · Engine
IHRA · drag
IHRA 2026, DD.5. A closed-list class. The craft must stay stock except where the rules allow otherwise, so anything unlisted is not permitted.
Read out of the published IHRA rulebook on 2026-09-11, so confirm anything that decides a purchase. The full note is at the foot of the page.
Read from the same class section as the part answers. The rider side of the sport, tiers, ages, licences and what gets inspected, is set out across the bodies at Racing.
Places where the rulebook contradicts itself, or where a figure could not be settled. Nothing in this list is decided, and it sits here rather than in a footnote because it is what you would want before spending money.
Confirmed absent by a targeted read rather than merely unnoticed. In a closed-list class an absent article is why a part reads as not permitted; in an open class it is why one reads as open.
33 permitted outright, 14 permitted with stated conditions, 3 refused by a rule we can quote and 20 refused by our reading of the class rather than by a quoted rule. Grouped where the same rule gives the same answer, so two "Not legal" groups can sit side by side under different rules.
Read the refusals as a list of work. Anything below marked Not legal, OEM part required, or Not permitted has to come off the machine, or go back to the standard part, before it races in this class.
Not legal1 part
Bolts, nuts and washers may not be substituted with titanium unless originally equipped. Locking mechanisms are allowed. J.7
Not legal1 part
Unless OEM-equipped. DD.5
Not legal1 part
Nitrous oxide is not permitted, and neither is a turbocharger unless the craft came with one. DD.5
Not permitted, not listed in the rules20 parts
On a closed list an unlisted modification is not permitted. A.2.2, J.1
Legal, with conditions1 part
J.7, in the general rules for every class, names wiring as replaceable with aftermarket options, which overrides the closed-list default and covers replacement wiring. Connectors are not named on their own, and J.7 does not open added inputs or outputs, a different harness design or an ECU. J.7
Legal, with conditions1 part
Must fit the original battery box and be securely fastened. J.9
Legal, with conditions1 part
Repairs are allowed for a crack or puncture, but only one damaged area affecting one cylinder bank. No other modification. J.11
Legal, with conditions1 part
May be modified or replaced with an aftermarket part. The original diameter must be maintained in Stock class, and the rulebook never defines which classes that is. J.18.2
Legal, with conditions1 part
May be replaced within OEM specifications. J.18.3
Legal, with conditions1 part
Aftermarket or modified, full-length type with at least one bar parallel to the driveshaft, dropping no more than 12.00mm (0.47 in) below the flat plane of the pump intake. J.18.1
Legal, with conditions1 part
Aftermarket or modified. An extension may not exceed the width of the original plate, and on a ski may not extend more than 100 mm (3.94 in). J.18.1
Legal, with conditions1 part
Replacement trim plates may be used provided they mimic the handling characteristics of the stock plates. J.18.2
Legal, with conditions1 part
Braking devices may be disabled for safety, and reverse buckets and trim motors may be removed or modified to disable them, provided no hazard is created. J.18.4
Legal, with conditions1 part
Aftermarket, modified, repositioned or removed. Up to two, each no longer than 36 in (91.45 cm), protruding no more than 3.94 in (100 mm) horizontally, at least 6 mm thick with radiused leading edges, and not attached to a planing surface. DD.5, J.16
Legal, with conditions1 part
DD.5 states "Aftermarket sponsons and steering components are permitted", which reaches a handle pole on any OEM craft the class admits. The drag section admits only what it lists. DD.5, DD
Legal, with conditions1 part
Replacement bumpers and side rails may be used provided they create no hazard. A permanently affixed nose bumper remains required. J.13, I.17
Legal, with conditions1 part
May be added to adjust handling. Constant mass only, and no other part may be modified to carry it. J.19
Legal, with conditions1 part
Under the general maintenance allowance a cooling hose or clamp may be aftermarket; J.7 names no cooling fitting. J.7
Legal2 parts
STRAIGHT PIPES ALLOWED. DD.5
Legal2 parts
Aftermarket superchargers are permitted, and DD.5 sets none of the gear drive or impeller limits of the Pro Stock and Spec classes. DD.5
Legal1 part
Aftermarket exhaust systems are permitted, the water box with them, and straight pipes are allowed. DD.5
Legal1 part
Aftermarket intake manifolds are permitted, with no limit stated on design or material. DD.5
Legal1 part
May be located outside the hull. DD.5
Legal1 part
Aftermarket throttle bodies are permitted, with no butterfly count or bore limit stated. DD.5
Legal1 part
Aftermarket injectors are permitted, with no limit on count or flow stated. DD.5
Legal1 part
Fuel cells and external pumps allowed. DD.5
Legal1 part
J.7, in the general rules for every class, names hoses and clamps as replaceable with aftermarket options, which overrides the closed-list default and covers an aftermarket fuel hose. Fittings are not named on their own. J.7
Legal1 part
An aftermarket ECU is permitted with no limit stated, which this site reads as covering a reflash, as DD.1 and DD.2 say in terms. DD.5
Legal1 part
An aftermarket ECU, standalone included, is permitted with no limit stated. DD.5
Legal1 part
Any gauges are allowed anywhere on the PWC. DD
Legal1 part
Named in the general maintenance allowance along with wiring, hoses and clamps. J.7
Legal1 part
May be replaced. J.8
Legal1 part
Aftermarket pistons are permitted, and unlike the Pro Stock classes factory compression need not be kept. DD.5
Legal1 part
Aftermarket crankshafts are permitted, where the other stock-based drag classes require the OEM crank. DD.5
Legal1 part
Porting allowed. DD.5
Legal1 part
Aftermarket camshafts and cam gears are permitted, with no lift, duration or timing limit stated. DD.5
Legal1 part
Aftermarket valves are permitted, without the OEM specification and no-oversize rule of the Pro Stock and Yamaha Spec classes. DD.5
Legal1 part
May be replaced, as may starters and oil injection systems, with the oil injection system removable or disconnectable. J.8
Legal1 part
Aftermarket intercoolers are permitted, with no size, type or mounting limit stated. DD.5
Legal1 part
Aftermarket pump assemblies are permitted, housing and stator vanes included, with no length limit stated in the class. DD.5
Legal1 part
Aftermarket nozzles are permitted together with aftermarket pump assemblies, with no length limit stated in the class. DD.5
Legal1 part
Aftermarket drive shafts are allowed, where the other stock-based drag classes keep the shaft stock, and no ratio or material limit is stated. DD.5
Legal1 part
Carbon-fibre hulls are permitted, and hulls may be swapped between any manufacturers. DD.5
Legal1 part
Aftermarket seats are permitted, without the OEM base, open-hole or seat-count rules of the other drag classes. DD.5
Legal1 part
Aftermarket seats are permitted, which takes in the cover. DD.5
Legal1 part
Grips, throttle and cables may be modified or aftermarket. The bar must be padded at the mounting bracket or the crossbar padded. J.17.1
Legal1 part
Steering shaft, holder, handlebar holder and cables may be aftermarket, and quick-turn modifications are allowed. J.17.2
Legal1 part
The bilge pump may be modified or disconnected and aftermarket bilge draining systems are permitted, provided they create no hazard. J.10
Legal1 part
Lightened hulls are listed outright, as are carbon-fibre hulls and swaps between manufacturers. DD.5
IHRA 2026, DD.5, read from the rulebook on 2026-09-11. Read the rule yourself, Drag, Super Stock. Every IHRA class · where the rulebooks differ · how this site reads a rulebook.
This is one class. Every part below also has a page of its own showing where it stands across every class this body runs, and legality by part is the index of them.
“Drag, Super Stock, IHRA class rules”, BaddJet archive, https://baddjetarchive.com/legality/ihra/drag-super-stock/
Add the date you read it.
70 parts read · 33 permitted, 14 with conditions · 2026 rulebook