shaftless butterfly system ?

[ECR]

Just browsing Premier Powers web site and see that they offer a shaftless butterfly system for their throttle bodies. I'm familiar with slide throttle, roller barrell and conventional butterfly throttles, how is their system different? Is it the case that there is no shaft running across the face of the butterfly?

Just curious...

[Tazio]

Roger,

Just ask SKC on here, Stuart Creswell, he is Mr Premier Power.

[oilyhands]

A friend made shaftless throttle bodies for Honda in BTCC, the throttle plate itself is essentially flat with the pivots diametrically at the outer edges , this gave an excellent profile across the throttle plate on full throttle, the surfaces of the throttle plates had micro indentations/wave forms like the dimples on a golf ball that created a thin boundary layer of air which reduced drag to an absolute minimum, airflow testing revealed there was no measurable difference between an open pipe and the same pipe with the carefully machined throttle plate on full throttle. The plates were machined from solid and gave some challenges in holding them while the surfaces were contoured. These were preferred to roller barrels since they give a more uniform airflow at part throttle and there was a significant weight saving.

Dave

[ECR]

Ahh, as I thought, thanks Dave