Gear Ratio Selection

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Badart

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I want to make sure I will be happy with my gear selection. The car is getting 29-15.5-15 hoosier pro-street tires. 440 727 combo. I have a set of 3.89 gears from mosier and I want to know if this a good choice. I plan using the car around town and very little highway use. I don't really have any plans taking the car to the track. Maybe someday. Does anyone know what rpm I will be turning at 60 mph? Thanks for your input.
 
there some calculators for that type of stuff around the web...i know bigblockdart.com has one....i punched some numbers into a calculator with the info you gave and it says youd be doing 66 mph at 3000rpm...thats with 0% converter slippage....all converters slip a bit, so with a number entered in for that you may get a different number...heres the link to the calculator i used

http://www.speedwaybids.com/calcs/mphrpm.html
 
With that tall of a tire 3.89s should be easy to live with....

I have 3.91s with E70-14s (about a 26" tire) and find them easy to live with.

With a 440 you have more options than my 340... You could go to a 3.23 (or dare I say, even into the 2s) and use your torque to get you around (Most livable in my opinion) while giving up little.... Or you could go the other way with the limited highway use, and make a stop light terror. 5.13s :D
 
Asuming a 29 inch tall tire.

Here is the formulae

rpm= mph x gear ratio x 336 divided by tire diameter or:

rpm= 60 x 3:89 x 336= 78422 diveded by 29= 2704 rpm
 
yea id stick with those gears....good compromise between nice acceleration and bearable highway cruising
 
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