One other possible, out-of-the-box solution I thought of would be to go with a hydraulic system. There are a number of custom applications like sand buggies that use hydraulics. They're a little spendy, but I think it might be possible to adapt a motorcycle hand brake/clutch master cylinder and a clutch slave cylinder to actuate the throttle. I got one to use as a way oiler on my CNC mill conversion.

....just a thought to add to the others proposed.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica