Dave, best thing you can do for more highway speed is get a higher rear end gear or overdrive trans. The 235 intake can work on your 216, has slightly larger intake runners, I ran one on my 261 for many years. But the 235 intake will not mate up to your stock 216 exhaust, so you can use fentons or just use a 235 exhaust.
Also you may want to check out
www.inliners.org
