{"id":5861,"date":"2014-05-29T13:59:48","date_gmt":"2014-05-29T20:59:48","guid":{"rendered":"http:\/\/www.racingjunk.com\/news\/?p=5861"},"modified":"2016-11-30T12:01:04","modified_gmt":"2016-11-30T20:01:04","slug":"three-pedals-on-the-floor-different-strokes-for-different-folks-part-iv","status":"publish","type":"post","link":"https:\/\/www.racingjunk.com\/news\/three-pedals-on-the-floor-different-strokes-for-different-folks-part-iv\/","title":{"rendered":"Three Pedals on the Floor: Different Strokes for Different Folks, Part IV"},"content":{"rendered":"

\"Clutch<\/a><\/p>\n

To read the earlier parts of this series, go HERE:<\/em>
\nPart I<\/a><\/em>
\nPart II
\n<\/a>Part III<\/a><\/em><\/p>\n

In the third part of this series, we began our look at modern dual disc high performance clutch assemblies. If you recall, we started our examination of McLeod\u2019s small diameter RST clutch package. \u00a0In this part, we\u2019ll conclude the series. There\u2019s something applicable here for just about any racer (at least those with three pedals on the floor).<\/p>\n

McLeod Racing\u2019s RST package effectively reduces the package diameter and at the same time, lowers the overall mass.\u00a0 So now, instead of using a large, relatively heavy 11.00-inch or larger Borg & Beck or Long style pressure plate, a small, light 9-11\/16-inch Diaphragm pressure plate can be used. Instead of using a big 11.00-inch or larger clutch disc, the system makes use of two small, lightweight 9-11\/16-inch organic discs.\u00a0 Obviously, the pair of discs increases the clamping power of the clutch (nearly doubling it over a standard single disc system).\u00a0 Because the clamping power has increased almost exponentially, then the demands placed upon the pressure plate springs are lowered.\u00a0 Just as importantly, the reduction in the clutch moment of inertia allows the use of a very lightweight pressure plate spring(s).\u00a0 That means your left leg is much happier \u2013 actually close to the same pressure as you\u2019ll find in a modern FWD econo-box.<\/p>\n

Mcleod\u2019s testing has show that the RST can handle up to 800 horsepower. The RXT is the same clutch kit but with upgraded Miba puck configuration discs (a \u201cMiba\u201d puck consists of a bronze segmented disc facing), capable of containing 1,000 horsepower.\u00a0 There are some options too:\u00a0 With the RS series of clutch packages, you can also specify an RST II (or RXT II) model.\u00a0 The \u201cII\u201d means the solid hub is replaced with a sprung hub.\u00a0 This setup is available in applications where there is sufficient space available in the bellhousing.\u00a0 Another option is the \u201cPlus\u201d series, available on RST, RXT, RST II and RXT II models. With this option, the clutch package includes a dedicated flywheel.\u00a0 Because of the developments, it\u2019s easy to see that something like the RST series (along with the variants) just might be the ticket in a dual-purpose street machine.<\/p>\n

In the end, if you\u2019re a \u201cthree pedal\u201d stick shift guy (or gal) you can name your poison! It\u2019s great to have good clutch choices.\u00a0<\/span><\/p>\n

 <\/p>\n

\"We<\/a>
We mentioned before that the pressure plate used in the RST clutch setup is an itsy-bitsy 9-11\/16-inch diaphragm job. Since the job of clamping is now handled by the pair of discs, it\u2019s possible to reduce the size, weight and course spring pressure in the pressure plate (just like a contemporary drag race clutch).<\/figcaption><\/figure>\n

 <\/p>\n

\"Due<\/a>
Due to the reduced moment of inertia (and coupled with modern pressure plate design), the chance of the pedal getting stuck on the floor at high engine RPM is gone too. And that\u2019s good news!<\/figcaption><\/figure>\n

 <\/p>\n

\"Although<\/a>
Although not a part of the RST clutch package (we pointed out previously the setup is designed to work with stock OEM flywheel assemblies or available with a steel flywheel), you can use an optional aluminum flywheel. McLeod have successfully mated aluminum flywheels to dual-purpose street-strip machines. Keep in mind this particular application for the aluminum flywheel on the street was a light car with a 572-cubic inch big block.<\/figcaption><\/figure>\n

 <\/p>\n

\"Since<\/a>
Since aluminum reduces the overall mass of the flywheel, it helps the engine to reach maximum RPM in a significantly quicker fashion. Naturally, aluminum wouldn’t survive alone in this oft-hostile environment. That’s why McLeod uses this steel heat shield that is fitted inside the flywheel. Note too that the flywheel carries an SFI tag. We touched on this in the second part of the series. You need this peace of mind, even with an aluminum flywheel.<\/figcaption><\/figure>\n

 <\/p>\n

\"Because<\/a>
Because aluminum isn’t particularly strong (when directly compared to steel of the same size), McLeod searched for ways to improve the structural integrity of flywheels manufactured from aluminum. McLeod decided to forgo the use of excessive milling on the backside of the flywheel. Many other lightweight flywheels are full of scallops, cut-aways and other weight reducing tricks. Unfortunately, this process unnecessarily weakens the flywheel.<\/figcaption><\/figure>\n

 <\/p>\n

\"A<\/a>
A steel ring gear assembly is mandatory on an aluminum flywheel, but you have to come up with a way to fasten the ring gear to the flywheel to insure it won\u2019t work its way loose. Here, the ring gear is pinned in place on the flywheel.<\/figcaption><\/figure>\n

 <\/p>\n

\"Here,<\/a>
Here, you can see how the ring gear pins effectively “sandwich” the flywheel.<\/figcaption><\/figure>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

To read the earlier parts of this series, go HERE: Part I Part II Part III In the third part of this series, we began […]<\/a><\/p>\n<\/div>","protected":false},"author":20,"featured_media":5869,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3465,11,3470,5012],"tags":[858,825,827,669,826,828,885,321],"class_list":["post-5861","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-drag-racing","category-how-tos","category-news","category-transmission-clutch","tag-clutch","tag-clutch-package","tag-flywheel","tag-mcleod-racing","tag-pressure-plate","tag-single-disc-clutch","tag-sure-plate-levers","tag-wayne-scraba"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.racingjunk.com\/news\/wp-content\/uploads\/2014\/05\/Clutch-21Feature.jpg","jetpack_shortlink":"https:\/\/wp.me\/p42YSK-1wx","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/5861","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/users\/20"}],"replies":[{"embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/comments?post=5861"}],"version-history":[{"count":3,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/5861\/revisions"}],"predecessor-version":[{"id":33228,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/5861\/revisions\/33228"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/media\/5869"}],"wp:attachment":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/media?parent=5861"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/categories?post=5861"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/tags?post=5861"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}