Drove to Providence, R.I. I set the cruise control at 80 mph and would stop and tank up after 400 miles. My red gas light never came on. I know it works because it comes on at 425 miles. Pushing my luck. Then I fill up with 20 something Gals. If I'm not mistaken my 78 has a 23.5 gal tank. You do the math. When I got up to Providence I averaged 22 miles a gallon. I couldn't hardly beleave it. ZZ4 385hp Aluminum fast burn vortec heads, 750 holly double pumper w/mechanical secondaries. and a Keisler 5 speed. That's without the A/C on. The temp never went over 195 degrees in heavy traffic. Most of the time cruising on the highway the dual electric fans didn't come on. As soon as I pulled off the highway 1/2 mile they would come on. Two miles on the highway they would turn off. After being there a couple of days. I hit a couple of bad pot holes and my stereo went mono. I think thats the word. Only one speaker on the left front would work. My friend who I bought the Vette from had another amplifier from 1978. Same as the one I have. Who would have thought. Anyway I put it and got stereo again. Got to Virginia and the right side cut out. That was the only bad thing that happened. I'm really glad that all my time and money payed off. She drives like a new Vette and looks like a old Vette. Just like old on the outside. Young on the inside. Save the Wave!

 

I bet it was the 5 speed tranny you have that did the trick

I'm thinking about one but it is way down on my list of projects.

 

Ttt