Editing Restrictor plate (section)

== Racing series ==
A few top classes like [[Formula One]] limit only the displacement and air intake mouth dimension. However, in 2006 air restrictors (as well as rev limiters) were used by [[Scuderia Toro Rosso]] to facilitate the transition to a new engine formula.

Many other racing series use additional air restrictors.

* [[Formula 3]], 2000cc, 215&nbsp;hp
* [[Formula SAE]], 710cc, 20&nbsp;mm restrictor.<ref>[https://www.fsaeonline.com/cdsweb/gen/DownloadDocument.aspx?DocumentID=64b861c2-980a-40fc-aa88-6a80c43a8540 Formula SAE Rules 2019 v1.0]</ref>
* [[Deutsche Tourenwagen Masters]], 4000cc, 470&nbsp;hp
* [[FIA GT Championship]] (now [[FIA GT1 World Championship]]) and other series using [[FIA GT Championship#Regulations|FIA GT regulations]]
* [[Le Mans Prototype]]s used in [[American Le Mans Series]] and [[Le Mans Series]] have restrictors based on precalculated tables depending on the type and size of the engine and fuel
** The ALMS in the [[2010 American Le Mans Series season|2010 season]] combines both LMP1 and LMP2 into a single LMP class on all races except [[12 Hours of Sebring]] and [[Petit Le Mans]]; LMP1-categorized cars use a 5% smaller air restrictor compared to LMP2- categorized cars to balance performance in the races<ref>[http://www.imsaracing.net/2010/ALMS/bulletins/IMSA%20COMPETITION%20BULLETIN%20ALMS%2010-01.pdf IMSA/ALMS Competitor Bulletin #10-01: Technical Specifications, 2010] {{webarchive|url=https://web.archive.org/web/20101205002416/http://www.imsaracing.net/2010/ALMS/bulletins/IMSA%20COMPETITION%20BULLETIN%20ALMS%2010-01.pdf |date=2010-12-05 }}</ref>