Transmission gear ratios

[sutyak]

I have a simple question that I believe I know the answer to, but I'm not coming up with the numbers I expected for my transmission.
In order to calculate the ratio for a certain gear, I need to count the teeth on the gear for one main shaft, count the teeth for the gear it meshes with, and then divide them. Correct?
So my 1st gear has 39 teeth. The counter gear on the secondary shaft has 14 teeth.
So 39/14 = 2.78:1 ratio.

Am I missing something?
Factory ratio is 3.38:1.
The only upgrade option from American Powertrain or GForce is a 2.90:1 first gear (and the rest of course).

[Martin0660]

You need the ratio between the input and the cluster shaft first. Input drives the cluster, cluster drives the gear that is engaged to the main shaft.

[sutyak]

You need the ratio between the input and the cluster shaft first. Input drives the cluster, cluster drives the gear that is engaged to the main shaft.

Well, bummer. I found this site: http://www.thecartech.com/subjects/a...ox_ratios3.htm that explains that in detail.
With an input shaft of 33 teeth and 4th gear of 40, the new calculation is (40x39 / 33x14) = 3.38, so it's a stock 1st gear.