<snip> > 210 lb/ft @ 1800 rpm). When you note the differences in rpm ranges > you'll see why I say "proper trans and gearing" is needed. The engine > needs to cruise near the torque peak. A 258 Concord works fine with > 2.35:1 axle in 82-83, but the four would need a lot steeper gearing (82 > Eagle used a 3.54 w/998, 2.73 with manual trans and low first gear) to > cruise around 3000 rpm. It needs to be at that rpm even in OD in order > for it to pull without using MORE gas. OD only reduces engine rpm for > cars with low rear axles. It's not as much of a gas saver as people > think, since to low in the rpm range will increase fuel consumption even > if the engine will pull the vehicle. It will help fuel economy some by <snip> The sweet spot for gas mileage depends on the engine and what the terrain is like around you. Smaller engines need more RPM but an AMC six or V8 (which make a lot of torque at low RPM) should be quite happy around 2,000 RPM at 65 MPH. If it's flat, you can get by with fewer RPM but you'd need more in a hilly area. Matt mhaas@xxxxxxx Cincinnati, OH http://www.mattsoldcars.com 1967 Rambler American wagon 1968 Rambler American sedan =============================================================== According to a February survey of Internet holdouts released by UCLA's Center for Communication Policy, people cite not having a computer as the No. 1 reason they won't go online. _______________________________________________ AMC-List mailing list AMC-List@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list or go to http://www.amc-list.com