Swap 3:36 unit for a 3:70 unit
02-16-2019, 07:02 PM
#5
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They use the same carrier so it will fit without a problem. However, if you go any lower you would have to switch carriers.
Last edited by 68hemi; 02-16-2019 at 07:04 PM.
02-16-2019, 07:03 PM
#6
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M20 is a wide ratio gearbox.....3.36 is a much better gear most of the time if the car sees any freeway use.
02-16-2019, 07:08 PM
#8
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That is true but most people are changing to a 3.70 or more low end grunt. The wide ratio gearbox that comes with the smaller h.p. cars std. also have a deeper 1st gear so it amplifies the stump pulling take off.
Last edited by 68hemi; 02-16-2019 at 07:09 PM.
02-16-2019, 07:16 PM
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If it is still the original trans then yes it would be the close ratio and another good reason to go with 370 gears. You will like the combination.
Last edited by 68hemi; 02-16-2019 at 07:17 PM.
02-16-2019, 07:28 PM
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02-16-2019, 07:37 PM
#14
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UOTE=68hemi;1598891902]Not many 365 h.p. Cars sold with anything less than 3.70 gears, the close ratio trans has a taller 1st gear and you really need 3.70s or lower to realize the full potential of that engine.
[/QUOTE]
I agree. The dealer I bought car from told me it has the 3:36 gear. I just bought the car in December so maybe I should verify it actually has the 3:36.
[/QUOTE]I agree. The dealer I bought car from told me it has the 3:36 gear. I just bought the car in December so maybe I should verify it actually has the 3:36.
Last edited by Mike65; 02-16-2019 at 07:41 PM.
02-16-2019, 07:50 PM
#15
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I just did the identical swap a couple weeks ago. I have a T56 Magnum with a 2.66 first gear and the 3.70 still makes a huge difference taking off from a dead stop. I swapped the entire differential, and it was quick and easy.
02-16-2019, 07:56 PM
#16
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Thanks for the reply Mike. The vendor that I am thinking about buying the differential unit from is asking If I have a 3 3/4 or the 4 1/4 yoke. Do you know the yoke size?
02-16-2019, 08:29 PM
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Close RATIO or wide RATIO refers to the gearing of the transmission itself. I think what you are getting at is that you have the shifter adjusted for the short-throw setting. The lever does not travel as far forward or back as when it's in the long-throw holes. Is that right? 
02-16-2019, 08:43 PM
#18
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Close RATIO or wide RATIO refers to the gearing of the transmission itself. I think what you are getting at is that you have the shifter adjusted for the short-throw setting. The lever does not travel as far forward or back as when it's in the long-throw holes. Is that right?
Last edited by Mike65; 02-16-2019 at 08:48 PM.
02-16-2019, 08:54 PM
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Right. I was addressing your statement you had the close ratio shifter. The shifter has no idea which transmission it is bolted to, and the stock shifter is the same for either close or wide ratio.