Re: 91 ford thunderbird sport 5.0
The most notable difference you'll see is going to the 3.73 gears. You should have 3.08 which are fairly long legs, great for top end and cruising but poor for coming out of the whole. Be advised that going with shorter legs will get up and go quicker, but you're not going to be as comfortable on a long haul. My truck has 4.11 in the back and around town she holds her tongue but cruising around 70... you might want some hearing protection. Right now you're sort of limited by the block itself. Knowing where your peak is on your power curve (in regards to RPM's) will help in the set up. I wouldn't think you'd be out running your fuel pump and I don't think the MAF will make that much of a difference. To some degree, you might notice a difference with the timing as well, it can vary, especially with cams, I'd start at 15 advanced and work towards 20. Old timers used to set the time, then go climb a hill, and keep advancing it until they start to ping.
Chewing on asphalt and drinking dinosaur wine