Jonny 290 posted:

I have manuals to scan/post and details to provide, but suffice to say that last night I read through the four inches of manuals the PO carefully preserved in a three-ring binder, and learned that my Mystery Lever is a "Decel-O-Matic" gas engine brake. Has butterflies on the exhaust pipes and an intake carb bypass. When you let off the gas, it closes the valves and bypasses air around the carb, to the extent that the big lever is pulled. This isn't just for hills - they advise to use it in stop-and-go, whenever you want to save your brakes basically. Max braking power on a 454 is about 30 PSI of backpressure.

In order to maintain this, they purchased the add-on "EZ-Oiler" system. This system is basically a solenoid and a tank full of MARVEL MYSTERY OIL - yes, they specify that in the book. To keep those exhaust butterflies flapping and your top end happy, they tell you at the end of the driving day to basically park, spray oil until, and I quote the manual, "significant smoke appears at tailpipes".

So those things explain the scary lever and about six of these switches and lights - there are various arming and enabling switches for both those systems.

This thing is so awesome.