IHRA · Exhaust

Stinger diameter reducing insert

IHRA answers this part for 14 of its classes. 4 of those answers are permissions, with or without limits attached, and 10 are not. 10 are inferred from how the class is written rather than quoted from a rule naming this part.

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This is one body's answer, not the sport's. You are bound by whichever body sanctions the event you enter, and where both govern you, you are held to the stricter of the two. The differences are set out in the rulebook comparison.

Where it stands, class by class

14 classes, grouped by the answer rather than listed one by one, because an answer that holds for a class usually holds for every class that borrows its rules.

Not permitted, not listed in the rules Our reading, not a rule we can quote at you. This class requires the craft to stay stock except where the rules allow otherwise, and this part is not on the list.

No rule, this is an open class Our reading, not a rule we can quote at you. This class carries no stock clause at all, so anything unlisted appears to be open. The rulebook does not say so in terms.

Not permitted, not listed in the rules 6 classes

On a closed list an unlisted modification is not permitted. · A.2.2, J.1

• Runabout GP2
• Sport Spec
• Runabout Limited
• X2 Vintage
• Ski Vintage
• Sport GP

Legal 1 class

Two-stroke craft may fit a stinger-diameter reducing insert. · Z.3.3

• Runabout GP3

Legal 1 class

The one exhaust change this class permits: an insert in the stinger to reduce its diameter, with cooling lines allowed on the insert. · O.2.5

• Ski Lites

Legal 1 class

A reducer may be placed in the stinger and a water fitting may be added. · M.4.1

• Ski GP3

Legal 1 class

Inherited from Ski Lites at O.2.5, and made largely moot by the aftermarket expansion chamber P.2.1 permits.

• Ski Limited · P

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

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Stinger diameter reducing insert: 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 · signed checks on parts the shop sells.