G-series 5th gear swap different in revs vs mph

[Team Lightning]

Here's a pict of my g series at 3K rpm and speed. This was the answer to a question on the Facebook page. I do not have a pict of the before the swap speedometer. If any one does or can get a pict, please post it. All my G series are 5th gear swapped.


IMG_2710.jpg

[FestYboy]

That's super close to the E series, if not nuts on. Now, could we do better? Say like 2500 at 75? That only another 17%....

[mikemounlio]

I can grab a picture tonight.

[Advancedynamix]

That's super close to the E series, if not nuts on. Now, could we do better? Say like 2500 at 75? That only another 17%....

Larger diameter wheels/tires.

[FestYboy]

But that would require recalibrating the speedo... A PITA. And we don't have the luxury of that much room.

[RdstrBlk]

Could we just do the math and change the speedo drive gear on the trans?

[Team Lightning]

This car has 185-55-15 tires. My speedometer is 1-2 mph off from my GPS on my phone.

[william]

I'm on 165/55/14's and g series and your about 650 less rpms then me and my speedo is about 7 fast.

[FestYboy]

Could we just do the math and change the speedo drive gear on the trans?

17% would be difficult in the trans, but there might be an adapter to suit that #. Looking into it...

The "larger" issue (pun intended) is the tire size Charlie is suggesting... It would have to be 25.5" tall, that's an extra 3.5 over ideal, a huge tire. (Example: 175/55-18 )

[RdstrBlk]

Sometimes the gear itself that drives the speedo cable is interchangeable between transmissions. Getting one with the perfect # of teeth isnt likely, but you can probably tighten up that 17%

[Team Lightning]

I'm on 165/55/14's and g series and your about 650 less rpms then me and my speedo is about 7 fast.

When I bought the car it had 165-45-15 tires on it. I hit a pothole in Greenville,SC coming back from Madness and destroyed the left side wheels. The Speedo was off 8-9 at 80 reading 71-72 on GPS. My DD tires are the 185-55-15's that are on it now. I have a set of 165-55-15's for autocrossing or use on my B6D car which has the E series trans.