There are five non-BMW classes, X1, X2, X3, X4 and X5. Class X5 is reserved for all non-BMWs with R-Compound tires (defined as having a treadwear rating less than 200). The remaining classes are based on vehicle displacement and modified according to the rules below.<\/p>\n

X1 = 5.0 Liters and up & all electric vehicles (Non-BMW 1)<\/p>\n

X2 = 3.7 – 4.9 Liters (Non-BMW 2)<\/p>\n

X3 = 2.6 – 3.6 Liters (Non-BMW 3)<\/p>\n

X4 = 2.5 Liters or less (Non-BMW 4)<\/p>\n

X5 = R-Compound Tire Cars Only (no matter engine size) (Non-BMW 5)<\/p>\n

After the base group is determined from the above table, move up one group as follows:<\/p>\n

-Increase one group if engine uses forced induction (either factory or aftermarket).<\/p>\n

-Increase one group if engine is rotary.<\/p>\n

X5 is specifically reserved for cars with competition tires no matter what engine the car is equipped with.<\/p>\n

Examples:<\/p>\n

-A 2018 Mazda Miata (2.0) would be in X4.\u00a0 However, a 2018 Fiat 124 Spyder (1.4) which is essentially the same car would be in X3 due to the turbocharger.<\/p>\n

-A 2010 Subaru WRX STI (2.5L) moves up from X4 to X3 because it has forced induction. Even factory forced induction, such as in this case, causes a car to move up 1 Group.<\/p>\n

-A 2010 Chevy Camaro V6 (3.6) would be in X3.\u00a0 A V8 (6.2) would be in X1 no matter the trim (LT, LS, SS, ZL1, etc.).\u00a0 The same car with R-Compound tires would complete in X5 no matter the engine size.<\/p>\n

-A 2008 Mazda RX-8 (1.3L) would be in X4, but is an X3 car because of its rotary engine. If the same RX-8 competes with R-Compound tires, it is in X5.<\/p>\n","protected":false},"excerpt":{"rendered":"

There are five non-BMW classes, X1, X2, X3, X4 and X5. Class X5 is reserved for all non-BMWs with R-Compound tires (defined as having a […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":34,"menu_order":2,"comment_status":"open","ping_status":"open","template":"","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"class_list":["post-881","page","type-page","status-publish","hentry"],"aioseo_notices":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/P6tMSo-ed","_links":{"self":[{"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/pages\/881","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/comments?post=881"}],"version-history":[{"count":10,"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/pages\/881\/revisions"}],"predecessor-version":[{"id":1281,"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/pages\/881\/revisions\/1281"}],"up":[{"embeddable":true,"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/pages\/34"}],"wp:attachment":[{"href":"https:\/\/nccautocross.com\/wp-json\/wp\/v2\/media?parent=881"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}