My 64 with a 230, three speed manual, and 4:11 gears whines a little on the highway. I have small 15 inch rims with low pro tires (sorry I just got home from work and don't want to check exactly what my tires are
). It humms at 60, my speedo is way off but that doesn't bother me. I only worry about overheating when I drive on the highway for a long time. One of my rear tires went soft so I took them off for a week and put some 16inch "whatever's" on it, the engine didn't rev as high on the highway and it felt just as stable at those speeds. Sorry, can't help you with the handling part. Good Luck.
