First, I would like to establish that Tim is in charge of all engine building. We may discuss any changes, but Tim has the last word. My job is to build the car, select the drive train to best get the horsepower to the ground, provide a little engine grunt labor and pass tech.
I have total faith in Tim's ability and flat cams or whatever else has been a gremlin will be over come. I also like the way he is driving, but, I will be back in the driver's seat before long.
My experience with final drive ratios is growing. I thought high gears would be the requirement to go fast. Wrong!!! In the first Y-Block configuration, it was making about 310 hp at the flywheel and not bad at 1.2 hp/cu. in. With that power, I started and stayed with 29" tires. The first ratio used was 3.70 and I did a best of 101, and that was in 3rd gear because it slowed down in 4th. I tried lower gears until I reached 4.33 and that was the optimum. That set up ran 118.9 at El Mirage, 124.6 at Bonneville, and 120.3 at Maxton, all records.
With the next couple of engine setups, additional hp was expected. I changed to 4.11s with 27.75" tires and that raised the final drive slightly. If we would have realized the additional 20 to 30 hp, the truck should have ran about 130. At 6700 RPM the tire speed would be about 135 and educated and experienced minds (not mine) think we would lose about 5 mph do to traction loss. This thinking was based on our speed, high co-efficiency of drag, and hp numbers.
I'm hearing 1 3/4" primary headers, higher compression pistons, valve size changes, all exciting stuff. Remember, this is not a stroked 312 with 500 hp which would require much higher gears.
We will be back................
Charlie Burns Laton, Ca (South of Fresno)
BurnsRacing981@gmail.com