I looked at Prestwich on line catalog, the items are numbered 1-XXX the zen falls at #7 I don't think this means it has 7 hp it certainly hasn't proven itself to have any more power than the QD as the QD is a full 10 mph faster in the SAW record trials.

Bring one of these 7.3 hp zens to a dyno facility and bring a QD, have both tested, the zen does not have the port area and does not have the ability to have the port area to support a power level equal to the QD, forget above as you mention.


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