throttle body

[JMD]

Can anyone describe, or provide links to info on formula one throttle bodies of the rotary variety? this might not be the correct name for them but they're not the butterfly design and not side throttles. they are also used in WRC's.

[desmo]

http://www.infiniti.com/docs/indy200...ne_barrel.html

[JMD]

nice pic but not a lot of info. do you know of any exploded views?
I had a look at the patent of the barrel throttle but I would like to see if there has been any advances or comparisons of flows through different throttles.

[desmo]

Barrel throttles have been around for decades, and share the advantage with slide throttles of unimpeded flow at WO throttle. They are conceptually very simple, just a tube with holes milled in it turning inside a housing. Of course in F1 the throttles are actuated by electrohydraulic means rather than a cable or linkage mechanism. Compared to slide throttles, barrel types are more consistant in part-throttle situations as slides tend to develop vortices and hence turbulence at part-throttle which manifests itself as comparitively poor drivability and a tendancy to be rich on transition from PT to OT which can be seen from Lambda data logged. Drivers also report better "feel" with barrels, so they have become universal in F1 and many other racing applications. Of course butterfly throttles are not even considered.