need help determining gear ratio
#1
need help determining gear ratio
I'm going to be upgrading my gears maybe to 3:43. However, I have no Idea how to tell what size I have in there. I know you should be able to tell by the sticker on the door but my sticker is gone. Anyway other way I can tell? RPM's at certain speed maybe. MY car is an A4 BTW.
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how many rotations does your driveshaft make for your tires to make one? I think that is a quick easy way to tell (not 100% accurate) but if it takes under 3 then you are rolling on most likley a 2.73... if its over 3 then most likley a 3.23 or higher.
(correct me if i'm wrong)
(correct me if i'm wrong)
#7
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Originally Posted by 94greencamaro
Easiest way to know
If you can select first gear: 3.23
If yoy cant select first gear: 2.73
If you can select first gear: 3.23
If yoy cant select first gear: 2.73
Best way to tell is to look at your GUx RPO code. If it says GU5, you have 3.23, if you have GU2 then it's 2.73.
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You can also drive at 70 mph in your 1:1 gear (3rd in an auto). Keep a load on the engine and check your RPM. If you're at 2730 RPM, you have 2.73s. If you're at 3230 RPM, you have 3.23s.
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Originally Posted by silvr002001
I'm going to be upgrading my gears maybe to 3:43. However, I have no Idea how to tell what size I have in there. I know you should be able to tell by the sticker on the door but my sticker is gone. Anyway other way I can tell? RPM's at certain speed maybe. MY car is an A4 BTW.
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Originally Posted by Captainofiron
You can call somebody at the GM dealer and run the VIN, they will tell you in a flash...... Or you could calculate the angular velocity of the wheel and compare the speed to the engine speed, that will also give you ratio.
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hahha yep it would. I had to do that on my 65 Impala. Actually it didnt take to long. I did it while I was sitting in my Art history class. That was one of the few times I didnt fall asleep.
#18
Just do it the most accurate way and pull the cover off and divide the numbers of
teeth on the ring gear by the pinion gear . (Driven gear divided by the drive gear.)
teeth on the ring gear by the pinion gear . (Driven gear divided by the drive gear.)