I changed my gears from a 2.44 (yes you read that right LOL) to a sure-grip 3.23 behind a 360 with a 727. Made the car a lot quicker but I easily could have gone with a 3.55 setup. It wouldn't have hurt the rpm at 60mph much. I would say go 3.55, you won't regret it, great all-round gear, fun light to light without losing out on highway cruising. JMO