changing gear ratio
changing gear ratio
- Thread starter frank334
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Old Dog
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something like 4:88's would probably work.
Try this link to figure it out. Gear Ratio Calculator
Try this link to figure it out. Gear Ratio Calculator
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There are quite a few gear ratio calculators out on the web.
Derf has made one:
Gear Ratio Calculator
This one looks pretty cool and user friendly.
Gear Ratio Calculator
Also there's charts showing rpm ranges here:
~ JR
Derf has made one:
Gear Ratio Calculator
This one looks pretty cool and user friendly.
Gear Ratio Calculator
Also there's charts showing rpm ranges here:
~ JR
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You didn't mention which motor, but if it's the stock F head you need proceed with a bit of caution. Even with the 5.38's, you will usually run out of power before you hit 4,000 rpm. Also, an Overdrive would be just as cheap as getting two sets of gears and getting it set up. Changing gears in Spicers is something that most people can do, but not for the timid, has to be done correctly, and requires a few specialized tools. On the flip side, a Warn/Saturn Overdrive is a 4 hr bolt-in. That would give you an approximate 4.0 final drive ratio. The OD can be used to split every gear, including low range and they can stand up to some pretty healthy power if you don't have a heavy right foot.
johnbilt
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I used to have a 56 M38A1 with the 134 F-Head. Not sure what ratio I had, but 55-60 mph was about the limit and the little 4 banger sounded like it was going to come apart at anything over 3000 rpm.
I would guess that using the ratio chart to get about a 300- 500 rpm drop at 55mph would give you more top end. The low range of the tcase will make up most of the offroad low end.
One gentlemen mentioned the warn Overdrive . This would be a nice way to get the best of both worlds. They are made for the Dana 18 tcase.
John
I would guess that using the ratio chart to get about a 300- 500 rpm drop at 55mph would give you more top end. The low range of the tcase will make up most of the offroad low end.
One gentlemen mentioned the warn Overdrive . This would be a nice way to get the best of both worlds. They are made for the Dana 18 tcase.
John