Cams are getting narrower?

[brages]

I noticed in some recent under-valve-cover pics how narrow the cams are. See The Critic's Audi 2.0T photos. And the Duratec 2.5 I saw had an interesting cam that is narrow in the "dwell" portion and widens out when it gets to the bump.

Anyone else seeing this? Seems like a newish development. I assume it's a friction-reducing approach to bump up that CAFE number just a bit.

 

[The Critic]

The Audi 2.0T cams are pretty special. They are hydroformed and the exhaust cam had slide-able cam lobes (with a ball and spring) for the VVT system.

 

[Chris142]

If it's a roller can you don't need much love I guess. Fwiw the stock cam in my 2002 jeep is 5/8' wide. The aftermarket ones are only 1/2' wide and are known to fail quickly.

 

[Rand]

If it's a roller can you don't need much love I guess. Fwiw the stock cam in my 2002 jeep is 5/8' wide. The aftermarket ones are only 1/2' wide and are known to fail quickly.

would that not be more about the metal quality and hardening?

 

[DriveHard]

I noticed in some recent under-valve-cover pics how narrow the cams are. See The Critic's Audi 2.0T photos. And the Duratec 2.5 I saw had an interesting cam that is narrow in the "dwell" portion and widens out when it gets to the bump.

Anyone else seeing this? Seems like a newish development. I assume it's a friction-reducing approach to bump up that CAFE number just a bit.

There is little to no contact force during the dwell, or even during the valve closing portion of the cam profile...no need for a larger contact area when forces are so low. Saves material, friction, rotating mass, etc.