I know very few people who have had anything to complain about a Olds "Rocket V-8" don't forget the 90 is the last one of those. Just a conversation topic.
You want underpowered get a 4.1. At least the 307 has the torque to move a 4200 pound car from a dead stop, the 249 has a 3.42:1 final drive ratio, takes off like a rocket when you take your foot off the brake, but it needs that just to get started. And has no power, absolutely none around 60. Step on the gas and it slows down, almost.
I forget weather the 307 came with 3.08 or 2.73 rear gears. Both are far favorable for highway driving, and can cruise all day at 70-80.