{"id":8255,"date":"2014-10-02T11:08:20","date_gmt":"2014-10-02T18:08:20","guid":{"rendered":"http:\/\/www.racingjunk.com\/news\/?p=8255"},"modified":"2016-11-30T16:42:21","modified_gmt":"2016-12-01T00:42:21","slug":"wheels-and-tires-from-street-to-strip","status":"publish","type":"post","link":"https:\/\/www.racingjunk.com\/news\/wheels-and-tires-from-street-to-strip\/","title":{"rendered":"Wheels and Tires From Street to Strip"},"content":{"rendered":"
\"Wheel<\/a>
When it comes to race wheels, most are manufactured by way of modular construction (which in turn allows for countless different offsets). Most race wheels are usually two, three or four piece modular sections. There are several different methods used to hold the wheels together: Welding, Rivets and Bolts. All of these systems have merit. These billet aluminum Champion Wheels are welded together.<\/figcaption><\/figure>\n

Picking the right wheels and tires for your car usually boils down to what fits and what’s on sale.\u00a0 There\u2019s a lot of monkey-see, monkey-do too — using what the local hero uses.\u00a0 The reality is there’s a whole bunch more to drag race rolling stock than you expect.\u00a0 And one area that seldom receives consideration is the fact that unsprung weight can actually affect performance.<\/p>\n

And when it comes to unsprung weight, there\u2019s very little data out there. In fact, it took a considerable amount of research to get to this point (and it\u2019s presented here).\u00a0 In the end, you might be surprised at how unsprung weight affects your car.\u00a0 And if that’s not enough, we also have some hard and fast rules on how to select the right wheel dimensions for your ride.<\/p>\n

First let\u2019s define \u201cUnsprung Weight\u201d:\u00a0 Unsprung weight is the part of the total vehicle weight that is not supported by the suspension springs.\u00a0 Unsprung weight includes the wheels, tires, hubs, rear axle (if a conventional non-independent arrangement — independent systems also include the hub carriers, but these systems are few and far between in drag racing) and brakes.\u00a0 Approximately 50% of the weight of the suspension links, drive shaft, springs and shock absorbers is also “unsprung.” \u00a0 What it all means is that the total unsprung weight is what the shock absorbers are forced to control (in the bump direction) so that the tires remain in contact with the track surface.\u00a0 The basics are easy too:\u00a0 The less unsprung weight there is, then the easier it is to control.<\/p>\n

Years (decades?) ago, we decided to tackle part of the unsprung weight equation by way of a computer simulation.\u00a0 We used a couple of different examples (one real, one imaginary) and ran them through a Quarter computer race program.\u00a0 The first was a 1969 Camaro complete with a healthy big block and a TH400 automatic with a transmission brake.\u00a0 The Camaro weighed in at 3500 pounds and carried a 4.88:1 rear axle.\u00a0 Wheels were heavy steel jobs while the rear tires were 9.00 X 30.00″ drag slicks (FYI, this was modeled after a car I owned at the time).\u00a0 The second car was a theoretical Chevelle \u2013 your typical weekend warrior powered by a mild 350 V8 (345 HP @ 5600 RPM), backed by a wide ratio Muncie 4-speed gearbox.\u00a0 The car weighed 3900 pounds ready to race and was fitted with a 4.11:1 rear axle.\u00a0 Again, the wheels were heavy steel models, but in this case, the tires were 10.00 X 28.00″ slicks.\u00a0 Both test cases were based upon the assumption that the respective chassis’ were sorted.\u00a0 In short, the cars hooked, but the Camaro was right on the edge of blowing off the tires.<\/p>\n

In both cases, the conditions were corrected to dynamometer “ideal” (zero elevation, 60\u00b0 F ambient temperature, barometer reading of 29.92 In. Hg and zero percent relative humidity). After a series of baseline tests were run on each car, they were fitted with lightweight wheels.\u00a0 With no other changes, the Quarter program predicted significant performance improvements.\u00a0 Check out the results:<\/p>\n

Camaro<\/b><\/p>\n

\n

– 60′ w\/ Heavy Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 1.62<\/p>\n

– 60′ w\/ Light Wheels: \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a01.61<\/p>\n

_____________________________________________________________<\/p>\n

Improvement = \u00a0 0.01 seconds<\/i><\/p>\n

– ET w\/ Heavy Wheels:\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 10.35<\/p>\n

– ET w\/ Light Wheels:\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 10.28<\/p>\n

____________________________________________________________<\/p>\n

\u00a0Improvement = \u00a00.07 seconds<\/i><\/p>\n

\u00a0<\/i><\/p>\n

– MPH w\/ Heavy Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 135.5<\/p>\n

– MPH w\/ Light Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 136.3<\/p>\n

_____________________________________________________________<\/p>\n

\u00a0 \u00a0Improvement = \u00a0 0.8 MPH<\/i><\/p>\n<\/div>\n

 <\/p>\n

Chevelle<\/b><\/p>\n

\n

\u00a0– 60′ w\/ Heavy Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 2.13<\/p>\n

– 60′ w\/ Light Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 2.11<\/p>\n

_____________________________________________________________<\/p>\n

Improvement = \u00a00.02 seconds<\/i><\/p>\n

\u00a0<\/i><\/p>\n

– ET w\/ Heavy Wheels:\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 13.23<\/p>\n

– ET w\/ Light Wheels:\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 13.14<\/p>\n

_____________________________________________________________<\/p>\n

Improvement = 0.09 seconds<\/i><\/p>\n

\u00a0<\/i><\/p>\n

– MPH w\/ Heavy Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 104.8<\/p>\n

– MPH w\/ Light Wheels:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 105.6<\/p>\n

_____________________________________________________________<\/p>\n

Improvement = \u00a0 0.08 MPH<\/i><\/p>\n<\/div>\n

 <\/p>\n

Fair enough, but what about performance in the real world? It takes big power to turn a big rotating mass, and the heavier the rotating pieces, the more power it takes to turn them. \u00a0According to folks who do this for a living, for every ten pounds you take out of the rotational mass, it’s like removing 17-1\/2 pounds from the racecar.\u00a0 Ponder that for a second:\u00a0 If you lighten each back wheel and tire by ten pounds, the car lost twenty pounds total.\u00a0 Peel another five pounds from each brake rotor (front and rear), then remove five pounds from each front wheel and tire, you’ve removed a grand total of 50 pounds of static weight.\u00a0 But when the rotational inertia is taken into consideration, it’s like removing 87.5 pounds from the car. And these figures are for a typical small diameter road race combination.\u00a0 As the tire diameter increases, so does the inertia.\u00a0 That means that a 33-inch tall tire under something like a Super Gasser stores plenty of it.<\/p>\n

Speaking of Super Gas, when yours truly worked for the old Super Stock & Drag Illustrated<\/i>, we became privy to testing by Sheldon Gecker.\u00a0 Using a 2400-pound, tube frame, four link Dodge Daytona Super Gas car as the test bed, Sheldon decided to A-B-A test different wheels.\u00a0 First, he had the old Monocoque Wheel Company build some “heavy” rear wheels (which wasn’t so easy).\u00a0 The first set of 15 X 15-inchers weighed (coincidentally) 15 pounds.\u00a0 Using his standard 16 X 33-inch Super Gas slicks (103-1\/2 to 104-inch circumference), the car was base-lined.\u00a0 It consistently ran 8.94 second ET’s.\u00a0 Switching to a set of 11-pound wheels, the car ran consistent 8.90 laps.\u00a0 Swapping the heavy combination back on the car, it slowed down 0.040-second.\u00a0 When the light wheels were added, the MPH picked up, but it was proportional to the lower elapsed time.\u00a0 In addition, the short times revealed that all the difference was seen down the track (more on this later).<\/p>\n

Gecker still wasn’t finished.\u00a0 Next, he tested a set of Monocoque bead lock wheels against the light combination.\u00a0 Given the design configuration of a bead lock, the wheels proved to be quite a bit heavier than the more conventional versions.\u00a0 Given the previous test, the results were predictable:\u00a0 The car slowed by almost one tenth (actually 0.090-seconds) when the heavy wheels were added.\u00a0 What had the most profound effect in the testing was the fact that the actual bead lock mechanism is in close proximity to the tire.\u00a0 That means that most of the weight is moved to the outer edges of the wheel which in turn increases the rotational mass (and consequently, the rotational inertia) dramatically.<\/p>\n

Those old tests came to a simple conclusion, and they happen to match our electronic test models:\u00a0 There is ET in light wheels.\u00a0 There is also some ET to be found in lighter slicks.<\/p>\n

There\u2019s one more consideration:\u00a0 Running the wheels tubeless (there are still a lot of racers running tubes with slicks): When running drag wheels tubeless, you can lose as much as five pounds per wheel.\u00a0 The only catch is you have to insure that the multi-part bolt-together wheels are properly sealed.<\/p>\n

Over the next three parts, we’ll talk more about wheels, tires and a working knowledge of these aspects of your vehicle can improve performance – on the strip, and on the street.<\/p>\n

\"This<\/a>
This 15X8 Champion Wheel weighs in at 13.7 pounds. Yes, you can get a lighter wheel but honestly there\u2019s a point where you trade a pounds for reliability (don\u2019t believe it? Watch a set of seriously light wheels as they\u2019re mounted with tires. You can physically see the rim deflect).<\/figcaption><\/figure>\n

 <\/p>\n

\"When<\/a>
When you measure a wheel for width, always measure from bead seat to bead seat, as shown here. This (obviously) is a 10-inch wide wheel.<\/figcaption><\/figure>\n

 <\/p>\n

\"The<\/a>
The distance from the bead seat to the wheel center determines backspace. As pointed out previously, there are plenty of different wheel, and wheel backspace combinations out there. We\u2019ll take a closer look at backspace in the next issue.<\/figcaption><\/figure>\n

 <\/p>\n

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

Drag Race 101: Wheels and Tires. These essential components of your vehicle are often overlooked when changing from street to strip. <\/p>\n<\/div>","protected":false},"author":20,"featured_media":8260,"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":[3448,3465,11,3698,9,5010],"tags":[961,1104,1371,1372,321,1370],"class_list":["post-8255","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-drag-race-101","category-drag-racing","category-how-tos","category-tech","category-tech-tips","category-tires-and-wheels","tag-drag-race-101","tag-drag-strip","tag-tires","tag-unsprung-weight","tag-wayne-scraba","tag-wheels"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.racingjunk.com\/news\/wp-content\/uploads\/2014\/10\/WheelFeature.jpg","jetpack_shortlink":"https:\/\/wp.me\/p42YSK-299","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/8255","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=8255"}],"version-history":[{"count":3,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/8255\/revisions"}],"predecessor-version":[{"id":8263,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/posts\/8255\/revisions\/8263"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/media\/8260"}],"wp:attachment":[{"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/media?parent=8255"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/categories?post=8255"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.racingjunk.com\/news\/wp-json\/wp\/v2\/tags?post=8255"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}