re: Jeeps: Improve fuel-efficiency of the Hurricane & Go-Devil Engines? One idea I had was to advance the timing a bit. In those days, lead was used as a softener instead of higher octane. So fuel would be at best 87 octane. Now it is 91 octane and advancing the ignition timing might help compensate for that. Skimming the heads and reducing the bowl volume may have the same effect but would need much more care to ensure that the piston crown does not foul with the valves. I am not even sure if Jeep engines need valve-train hardening or lead additives to make them run smoothly and for many thousands of kilometers, or not.
Another idea would be to use the correct spark-plug range. A plug chart for NGK, ND, Bosch, and other equivalent plugs will go a long way in ensuring that owners of petrol jeeps use the correct spark-plugs. Note that NGK denotes a warmer plug with a smaller number (so an NGK 7 is a hotter plug than an NGK 9) and Bosch with a higher number (so a W5 is a colder plug than a W7). |