This is way more relevant to my project than chance should ever have it...
I want to re-power a Sidekick with a unique 285hp 4 cyl, drive it daily including winters here in western Canada (snow).
So, for me a hugely important aspect is that the ratios don't jump, especially 3-4, and 4-5, and that they reduce the jump as speeds increase. IE, RPM drop from 4-to-5 is less than 3-4, is less than 2-3. That means the AR5 and a bunch of others are simply out. The Solstice has jaw dropping badly chosen ratios. 45% rpm change 3-4th- ideally it should be a half of that! For too many years my family drove a Volvo with 4.03 first, 3.73 FD, and 185/70r14 tires. First gear was useless, but the ancient K-jet engine management and too-large-from-factory cam, meant you absolutely had to use first to get moving. There was a lot of flywheel effect and the laggy engine management made that seem far worse. Then 2nd gear was 2.18, IIRC. Dumb. The first vehicle I "built", I went with more power, less weight, 3.13 first, 3.31 FD, the lightest flywheel I could, and 205/60r16 tires. Still have that car ~20y later, and if I say so myself I nailed the specs dead on. If anything, everything could be taller. A 3.07 F/D or taller tires.
So with the future project, I narrowed it down to the 98-02 V6 Mustang T5 with 1.29 3rd, and with an aftermarket closer 5th (.89, IIRC- it's sitting near me as I type), or a specific Toyota trans from the late 80's. The T5 bolted up, the other required a lot of searching. Later, I came on the Mazda 6spd (Miata/Rx8) but it would require even more work (but they "got" what ratios it should have!).
I was limited in F/d ratio because I wanted to keep the front diff & housing, and ratios for it ranged from 5.125 down to 3.73, so I did the latter. Am going with a 28.5" tire. Would have preferred a numerically lower f/d for flexibility to go with smaller tires, but...compromise. Besides, average tire size on the market has been growing....28-29" is where all the new sizes are hitting.
So, style your body with tolerance for tire size. Use that as your out.
A v8 turning too many RPM lends very "busy" feel to a car. Very unwelcome imo. I'd look at 3.08, myself. Can you get that for front?
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