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Old 05-31-2003, 01:09 PM
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haasman haasman is offline
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Join Date: Jun 2001
Location: San Francisco, CA
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Whether you can use the benefits of cross-drilled rotors is for you, of course to decide, but I find the "cosmetic" comment troubling. If that were true then Mercedes, Porsche, BMW, Ferrari etc all are installing faux components on their 2003 automobiles.

I suggest that there is more to this topic than a fad. All brakes generate gases as a partial by-product of braking. To allow the gases to escape increases the effectiveness of the pad against the rotor, called venting. The well-known benefits of cross-drilled and/or slotted rotors include smoother braking, greater stopping capabilities, reduced brake dusting, excellent wet-weather braking and often longer rotor life, depending on use and pad applications.

I crewed for several Porsche race teams in the early 70's. The rapid adoption of cross-drilled rotors was met with mixed success: They stopped cars better, dramatically improved wet-weather braking and reduced unsprung weights. Race drivers reported initial brake application gripping as slower (cooler rotors) but also found greater braking effectiveness and fade resistance. These rotors were rapidly adopted across the board.

The original cross-drilled rotors often failed due to cracking around the holes. The second-generation cross-drilled rotors had chamfered edges around the holes that all but eliminated the problem and is what one sees now on all cross-drilled rotors.

The first street application by a manufacturer was the Porsche 930 (911 Turbo) in 1979. Porsche has continued to install cross-drilled rotors on their cars since. If they were ineffective, or worthless, why wouldn’t they have been removed years ago?

The standard Mercedes brake rotor is vented and is time and Autobahn proven so why bother to upgrade? Because there is a newer solution that companies such as Mercedes, Porsche, BMW and Ferrari all have adopted.

Will your use justify their installation? I see it as for almost the same amount of money as a standard rotor, you can improve your braking.

'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)
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