[DeTomaso] optimum ZF ratios

[MikeLDrew at aol.com]

In a message dated 1/11/10 18 40 43, dgordon100 at cox.net writes:


> If buying a new ZF from RBT, what would be the optimal ratios for each
> gear and final drive given a max torque of approx 600+ ft/lbs at 4250
> and max horsepower of approximately 700 horsepower at 6500 rpm both
> measured at the wheels? I would thing that after each gear change it
> would be desirable to not drop below the peak torque rpm providing I
> shift at 6500 rpm.
> 

It's a highly academic question, because you'll have enough power and 
torque to alter the rotation of the earth anyway.   Most likely, the limiting 
factor will be tire traction.

That said, there's a wonderful ZF gear calculator on Mike Dailey's website:

http://www.panteraplace.com/page32.htm

If you click on that link, it will download an Excel file to your hard 
drive.   Open it, and you'll find a program that tells you exactly what you need 
to know.   It's pre-loaded with standard ZF gearing (plus an optional sixth 
gear), but you can change the values for tire diameter, rear-end ratio, and 
each gear ratio.

I just recently figured out that there are tabs at the bottom; if you click 
on the other tab, it presents the data in a graphical format.

Unfortunately the cells aren't formatted very nicely; I fixed it on my 
personal copy, and will e-mail that to you directly.

Mike