3 Attachment(s)
Carrb linkage & fuel rail
You just can't imagine how much time it takes to engineer and build throttle linkage and a fuel system for six carbs. Factory OMC looper choke linkage pieces were scavenged from a "box-o-carbs", hammered into new shapes, and now serve as inter-carb linkage. As noted before, a trick to mounting carbs close together was to reverse the port side butterfly shafts. Careful planning and delicate rework was involved. Be aware you MUST grind the protruding, swaged portion of the screw from the back side of each butterfly screw or they simply break off upon removal! One butterfly shaft was ruined in the process. The throttle pulls were made from bicycle brake cable & housings. The cables will be terminated together at the dead-man cable attach point low on the port side of the engine.
Fueling six carbs with three pumps looked at first to be a plumbers nightmare. After several scenarios were sketched, it was decided to use one main fuel inlet to feed the three pumps (and the primer yet to be mounted; the pumps in turn feeding six carbs. But how to make sure all are fed evenly? Elementary: A vertical fuel rail was gun drilled, machined, and attached as shown. Pumps feed the common rail from the top, middle, and bottom. Carbs are then fed by individual equal length hoses spaced in between. Fittings are due in tomorrow, with hoses to follow. It's sure to look interesting, especially once the primer and its hoses are fitted!
Tim
Challenges to be overcome
Quote:
Originally Posted by
BJuby
I was looking forward to seeing how you were going to accomplish the throttle linkage. Very clever and professional looking.
Thanks, but it's not done quite yet. All my race engines use push-to throttle actuation for safety. That way closure is not totally dependent in springs: You can forcefully pull the throttle handle back to close the throttle should the Bowden wire bend. The 666 is obviously a pull-to, so a reversing arm must be designed and built. Hopefully in the next few days.
Tim