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Ok….. and how is that 224:1 attained?I'm running an auto with a 224:1 final drive ratio.![]()
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Ok….. and how is that 224:1 attained?I'm running an auto with a 224:1 final drive ratio.![]()
His black box is 2.72:1 in front of the hf2a which has the 3:12 low range gears.What trans? 5.29s? That's a deep first in an auto.
With 5.29s that still needs a ~5:1 first gear, right?His black box is 2.72:1 in front of the hf2a which has the 3:12 low range gears.
The math is all in my build thread somewhere.1.7 multiple in the converter before lockup.
Number of engine revolutions for number if axle revolutions.Oh, didnt think most people use the torque converter multiplier in their gearing calc.
It makes sense, but with decades of playing with this stuff I've never seen anyone calculate it that way.Number of engine revolutions for number if axle revolutions.
Since you'll never get an auto to lock up that low, it seems legit. I just stole Slee's math.
My entire point earlier today was that, as much as I appreciate manual transmissions, and agree that the auto box saps power, with an exclusively Toyota power train in an 80, for rock crawling, the slushy auto is preferred over a manual because the torque converter helps multiply torque and put power to the ground more controllably and usable.The math is all in my build thread somewhere.
I've seen it done both ways. The slower crowd seems to include the TC multiple more often. I used to calculate static ratio for years, but found it wasn't a good representation of the number of wheel revolutions i was getting at a given RPM.It makes sense, but with decades of playing with this stuff I've never seen anyone calculate it that way.
Agreed, and TBH i actually don't use low-low very often. It is nice to keep the rpm up for the steering though.My entire point earlier today was that, as much as I appreciate manual transmissions, and agree that the auto box saps power, with an exclusively Toyota power train in an 80, for rock crawling, the slushy auto is preferred over a manual because the torque converter helps multiply torque and put power to the ground more controllably and usable.
Your transmission has less to do with your 224:1 than that black box.
I leave the AC on all the time for thisIt is nice to keep the rpm up for the steering though.
Agreed. I like the control.No mater the gearing I prefer a auto ! One foot on the break and one on the Gas for best control![]()
Time for a hydro booster.Agreed. I like the control.
Going to have to upgrade the brakes though. Low-low overcomes them pretty easily, even just off idle.