2600 rpm's at 60 mph ...wow, I will keep your RX(auto r180/3.545 ratio) for future mods. What tranny completes this formula?

Doing the math:

2600/3000=.86666

From the link I posted, that would be a 280Z 5 speed.

It was actually from a Japan Domestic Fairlady 2000cc. But then it may not have been origional to that car either.

My understanding is fourth is direct drive on a these gearboxes, (but then I may be wrong), and fifth is an overdrive.

It was actually from a Japan Domestic Fairlady 2000cc. But then it may not have been origional to that car either.

My understanding is fourth is direct drive on a these gearboxes, (but then I may be wrong), and fifth is an overdrive.

D'oh! There goes the American in me.

The OP could get the same ratio from a 280Z 5 speed.

I do know there is quite a gap between 2nd and 3rd in this gearbox from a JDM. Fairlady.

Could be the wide ratio steel synchro box. IIRC the ratios are pretty close to the 280Z 5 speed, which also has a big 2-3 gap. The close ratio box is pretty close to the ZX 5 speed.