Thanks for the nice compliment, Danny. I hope all's well with you and yours in New Mexico. My Duster has it's original 7 1/4" rear diff with 2.76 gears. I don't know what RPM it runs at 70 mph because I don't have a tach. My guess is that it's about 3100. The engine is definitely not straining at that speed and doesn't seem especially loud and overtaxed. In fact, the motor seems very happy and comfortable at 70, runs nice and cool at 195 degrees, and would happily do it all day. The 225 motor/2.76 axle seems to me like an excellent highway setup. I've had no problems at all with it and can strongly recommend it. You'll have no problem running it at 70. My Charger is a bit different. The 440 engine feeds a 8 3/4" sure grip axle with 3.23 gears. At 70 mph it's turning at 3400 rpm and is noticeably loud. My V-8 powered Lexus turns at about 2300 rpm at 70, so you can see the difference. The Charger, of course, has enormous amounts of top end torque for passing which the Duster doesn't have. But the Duster can pass and accelerate just fine at 70. No problems there. So the Duster motor is turning slower than the Charger motor at 70 mph. Interesting.
