How often do you drive 55 or higher? I don't. I rarely drive in a zone 55 and above. I mostly drive in zones 45 and slower. My 3.55 turns the engine around 2600 rpm at 55. If you're in the same boat as me, consider a 3.90 or 4.10. I'm planning on a 4.10.

I'm interested in street performance. For this you're generally looking for a first gear final drive ratio of 10:1 or a steeper. Take the M22 cars for example. Cars with this transmission usually came with a 4.11 because of the high 2.20 first gear. 2.20 x 4.11 = 9.042. Even this setup fell a little short. My 2.56 x 3.55 = 9.088 fares a little better. But with a 4.10 I'd end up at 10.496. Perfect. A 3.90 gear would put me at 9.984. This would do really well too. Given that I don't drive fast, I can run a steeper gear.

To bring the revs back down when needed I'll get a Gear Vendors OD. With its .078 OD, it'll bring the gear down to around 3.20. This would be a great highway gear.