OEM part required 3 classes
Must remain OEM.
- Runabout Lites · AA.3.1
- Runabout GP2 · Y.3.1
- Runabout GP3 · Z.4.1
IHRA · Fuel
Aftermarket intake manifold, IHRA
IHRA answers this part for 29 of its classes. 5 of those answers permit the part outright and 2 permit it with stated conditions, leaving 22 that do not. 4 of the ones that do not are classes we read as open rather than as refusing it. 14 are inferred from how the class is written rather than quoted from a rule naming this part.
This page is IHRA only, and the bodies do not agree. The same part under IJSBA and UIM. Which one applies to you is decided by whoever sanctions the race you enter.
Where it stands, class by class
29 classes, grouped where the same rule gives the same answer rather than listed one by one, because an answer that holds for a class usually holds for every class that borrows its rules.
What each answer below means
- OEM part required
- This comes off. Only the part the manufacturer fitted is allowed here.
- Not permitted, not listed in the rules
- Treat it as coming off. The class requires the craft to stay stock except where the rules allow otherwise, and this part is not on the list, so this is our reading rather than a rule we can quote at you.
- Legal, with conditions
- Keep it, but measure it: the rules permit this part only inside stated limits.
- Legal
- Keep it. The rules permit this part in this class.
- No rule, this is an open class
- Probably keep it. The class carries no stock clause at all, so anything unlisted appears to be open. The rulebook does not say so in terms, and this is our reading rather than a permission anybody wrote down.
OEM part required 1 class
W.3.5 names no aftermarket manifold. A Yamaha SVHO may run any OEM Yamaha manifold, a plastic one may be backdated to its metal predecessor and the ribbon may be deleted, while a Sea-Doo 300 or 325 keeps its stock manifold and ribbon. The aftermarket component W.3.5 allows is one fitted where needed to hold the original OEM airflow after a ribbon is removed, not a replacement manifold. · J.1, W.3.5
OEM part required 1 class
The intake manifold, with its screens and spark suppressors, must remain stock. · N.3.1
OEM part required 1 class
Must remain OEM and interchangeable between WaveRunner models, with vacuum fittings, upgraded throttle body spacers and ribbon deletes permitted. · DD.1
OEM part required 1 class
Must remain OEM. Vacuum fittings and ribbon deletes permitted. · DD.2
OEM part required 1 class
Must remain OEM. Vacuum fittings, spacers, ribbon deletes permitted. · DD.3
Not permitted, not listed in the rules 9 classes
On a closed list an unlisted modification is not permitted. · A.2.2, J.1
Not permitted, not listed in the rules 1 class
A turbo feeds the engine through its existing intake manifold, so reading DD.7 as admitting the turbo's own installation does not open an aftermarket manifold, and DD.7 does not list one. · DD.7
Legal, with conditions 1 class
Model-dependent. N.3.1 keeps the intake manifold, screens and spark suppressors stock on a four-stroke entry, and P.1 grants no exception, while P.2.4 lets a two-stroke entry run a modified or aftermarket intake manifold assembly. · P.1, N.3.1, P.2.4
Legal, with conditions 1 class
Model-dependent. Two-stroke entries may run modified or aftermarket intake manifold assemblies under BB.5.1, while the four-stroke rules in BB.4 name no manifold, so a four-stroke entry keeps its own. · BB.4, BB.5.1, J.1
Legal 2 classes
Aftermarket intake manifolds are permitted, with no limit stated on design or material.
- Drag, Sea-Doo Spec · DD.4
- Drag, Super Stock · DD.5
Legal 1 class
Intake manifold assemblies may be aftermarket or modified under K.4.1. · K.4.1
Legal 1 class
The intake manifold assembly may be modified or replaced with aftermarket parts, for two-strokes under V.3.1 and four-strokes under V.5.1. · V.3.1, V.5.1
Legal 1 class
Intake manifold assemblies may be aftermarket or modified, as X.3.1 and X.3.3 allow. · X.3.1, X.3.3
No rule, this is an open class 3 classes
The class states only what it bans and calls itself run what you brung, against a section DD preamble that says anything unlisted is illegal.
- Drag, 2 Stroke Unlimited · DD.12
- Drag, Stand Up Unlimited · DD.10
- Drag, Unlimited · DD.6
No rule, this is an open class 1 class
No restriction in section CC, and CC.1 permits any modification it does not restrict.
- Freestyle · CC
Aftermarket intake manifold: if the rule your class applies reads differently to you, or the rulebook has changed since this was read, ask. We answer with the section we read it from, or that we have not read it. Ask a rules question.
Every IHRA class · where the rulebooks differ · checks on parts the shop sells · how this site reads a rulebook.
Fuel · two and four stroke · legal in 7 of 29 answered, 2 with conditions