[MZ3 SBC]

Originally Posted by RarlyL8

I was thinking in terms of gearing to optimize torque, not gearing just as an overdrive to stay out of boost while cruising. That's a different deal. Do you normally run at 110mph?
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I was thinking about your comment Brian. ...I wish I was driving at 110 all the time. The fact that I am not driving at those speeds and higher often is exactly why I would like a taller 4th....I dont really mind if going taller in 4th will cause a bigger step from 3rd to 4th since I will not be racing at those those speeds....but using 4th to comfortably drive on the highway. I want the same gearing in 4th that all the stock geared 930 have today......thats (9.38 /.625 or 8.41 /.514)....so I think we kina agree on this.

Where my view is different pertaining to not needing gearing when more boost can be had ( if thats what you said) ...is that I think shorter gears with or without a turbo....and regardless of whether you have low spooling turbo or not....is faster. Is it required? certainly not ...and much less so with a low spooling turbo.

But the bigger the wheel the torque the faster the car will accelerate....to the maximum / peak RPM a motor. the turbo just helps you accelerate faster....provided the turbo can spool efficiently to the red line as well. Thats my take. The one part of the calculus that I would love some one to comment in on...is how gearing and time in each gear effects spooling / heat for turbo....My guess it it makes no difference how quickly a car accelerates to 6500 RPM...so why not accelerate as quickly as possible....

I recognize that choosing gearing stacks for different road courses introduces a different set of variables ....and you have to select the gearing that will be most effective to improving lap times.....Nurburgring /Road Altanta vs Limerock ( differet topic)


The 8.41 helps get the car going quickly and then the boost joins in on the fun....and the motor with SC cams and ported intake helps he motor rev ....adding a lower spooling turbo like the K27 7200 Raptor will only make things better.....

and if you want to accelerate from 0 to 150 with your stock gear stack and dont care about 600 more RPM in 4th gear for a given speed on highway....then the 8
.41 or 8.37 is faster than 9.38.....RUF had it right! short 1-4 and a real overdrive 5