I've been pushing Homer the Super Bus (a 73 with a 79 tranny) down the road with bone stock type 1 engines for several years. As long as it's in good shape and properly tuned, a stock 1600 single port will do fine . . . you won't be doing any burnouts and you may have to downshift to 3rd when you are climbing a mountain . . . and if you over load the bus and stick a big trailer (also overloaded) behind it, get ready for folks to wave one finger at you when you hit steep hills on the interstate . . . but it'll get you there eventually.
I've driven Homer to Tampa 3 times, Jacsonville, FL twice, Effingham, IL twice, and Nashville, Seveirville, Hunstville, Birmingham, Atlanta, and Tacoa countless times.
If you spend a little money and build a good solid 1776, you'll have the best of both worlds . . . the HP of a stock type 4, and the economy of a type 1.
If you really want to do a type 4 right, get Jake Raby to build you an engine. It'll smoke the tires, get 30 MPG and run 100,000+ miles without a problem . . . but you better rob a bank before you go talk to him . . . :shock: