5th Gear swap
I decided to lower my RPMs while cruising on the highway (to get better gas mileage & for less stress on the engine). First, I needed to find out what my current gear ratios were. To get that, I had to find my tranny code. Normally this is on a sticker in the wheel well, but mine was worn down and unreadable. The below photo shows the area on the tranny where the engraving is. The important info is the first three characters which in this case are EGX:
My tranny has the following gearing:
1.8T trannys coded: EBQ, EMT, EGX, FBW:
I purchased a taller 0.717 5th gear from a TDI that will meet my needs. The associated P/Ns are:
Here is the theoretical RPM-vs-Speed graphs for my cars. I know some of the lines are hard to see at first, but I'm sure if you take your time you'll see where they all are. What I notice is that my Golf's old 5th gear (solid yellow) was identical to my S4's 5th gear (dashed yellow). My new (0.717) 5th gear(solid white) is now identical to my S4's 6th gear (dashed teal - hard to see, directly under the solid white). And these are both taller than the GLI 1.8T's 6th gear (dotted teal).
Note: these are indeed *theoretical* based on a sold circular
tire of the stock dimensions listed. In reality, these values change as the tire
isn't a solid circle. Since I computed these all in the same method, I feel they
are valid to compare to each other. Separately, I have found that the actual
Speed-vs-RPM that the car's computer sees is different, and I have also noted
that the gauges are also different from that. More to come....