Catching up, and enjoying the work you’re doing.
220 was my top end, too, before the updated radiator. The 130gpm pump, dual thermostats, a big fan, and the dual pass keeps everything steady at 210 while running 2700 in 3rd and cresting the pass at 55mph. These engines make a lot of heat, and it took a race car radiator to keep it cool.
You’ll enjoy the process and the payoff.
I agree. The noise break over is significant from 1800 to 2200, as is the mpg hit.
If I ran my 37s with a big stinking turbo and intercooler, I’d run 4.56s at the max. With enough air, the engine will build torque nicely as boost catches up on a grade in the 1800-2100 range, and you have room to downshift and use 3rd at 2500-2800.
Everything has a rev level, and this box you’ve made seems to work very well.
David
Appreciate the encouragement. Regarding the gearing, my current plan (subject to change) is to stick with the 4.10s when I go to 37s I seem to remember my NA 6.5 being very happy with the military 37s I had before. So I should see a better RPM range.
As for the box, it’s been kind of cool putting my wood skills and tools to use building this. It’ll probably be used for quite a while and will make a good prototype for whatever I come up with next.


