I'm starting this thread to pressure me a little to actually noodle this through.
What I need to figure out is whether I can even practically
use a taller 5th gear, considering that my transmission swap already reduced my engine RPM in all gears for a given road speed by almost 26%. (The taller final drive lowered RPM by 19.8%. Add the tire size difference between the Swift where the transmission came from, and the Metro, and it makes for a total effecive RPM change of 25.6%.)
Why do I want an even taller 5th? Because I think it would suit my driving style for highway cruising: driving with load (DWL). I don't like using pulse & glide for long drives.
Of course, if you have a Metro and have looked into this, you already know there is no 5th gear set that can just be swapped in.
More likely it'll require a custom made set - I'm thinking something along the lines of the approach described in this thread:
http://ecomodder.com/forum/showthrea...t-zx2-763.html
He took a set of 2nd gears from the same transmission, flipped and mated them to the hubs of his old 5th gear set. Dropped his RPM by nearly 1000 rpm at 70 mph, though.
I know a machinist (the guy who made the ForkenSwift's motor/transmission coupler), and he might not charge me crazy beans to do this. Certainly not the $550-800 that was quoted when
someone on Teamswift offered to do custom 5th gears for people (and it never panned out).
So, I need to do the calcs. Tim (Daox) sent me a handy spreadsheet for plugging in gear ratios that spits out a nice graph of RPM / MPH. I need to actually do it with the reversed 2nd gear ratio.