a4ld gears

[youngPSD]

Is there a rule of thumb to figure what final crawl ratio with an automatic is. I see that first gear is 2.47:1 is there a way to tell what the torque conv. ratio is. i was running doublers in my head and saw that atlas says no more that 3.8:1 with automatic?

 

[Viper Command]

The TC is only 1:1, atlas says that because in an auto at idle and in low, the brakes cant hold back the trans.


http://www.izook.com/gearcalc.htm to find your ratio.

 

[youngPSD]

i know that when the conv. locks its 1:1 but is there a way to tell what it is when i put it in first gear or does it just work ?

 

[Viper Command]

there is no ratio for the TC. it just slips, there is no torque gained, just heat and lack of power.

I was told that a non lockup TC slips 8-15% from 1:1 depending on truck weight, TC size, stall speed.

If you had a c4 trans you can get the trans brake Valve body for it and use the atlas10:1 low range.