As they come stock with 4.11s and I don't want to max out at 50mph
I put quite a few trouble free miles on my '50 with a 216, 3spd, and 4.11s, highway cruising at around 60.
It now has a T5 (.76 5th?) and a 3.90 rear behind the 216, and it cruises comfortably at 65.
I agree with Phil and RonR above. A few times with a slight downhill run on the highway, I've tickled some upper 70s just enough to register on the GPS speedo on my phone before I backed off to a comfortable cruising speed. One hot day coming home from work last summer, floored in 5th on a flat stretch of I45, it topped out at 72 for about 3/4 mile. The RPMs were just fine, it just didn't have the beans to climb any higher.
