For a converter, you want your stall speed to be below the RPM you drive around all the time at,.
I don't agree with this^ and I believe it to be a common misconception for street driven applications. I had one car for over 3 years and put 55,000 miles on it in that timespan. it was my daily driver which I also drove to work and back 5-7 days out of every week, 12 months out of the year. In the winter time I put snow tires on it too.
This daily driver I spoke of turned 12.0 ET's and it was strictly a pump gas engine under the hood. i had a stall speed of 3,000 RPM and around town a typically cruised around at 2,200-2,400 RPM, and I never had any problems. The thing about stall speed vs. cruise RPM that many guys overlook is that your torque converter will only flash to the max stall speed during full throttle when the full torque of the engine is applied to the drive train. And when you're cruising around town, the full torque of the engine will NOT be applied to the drive train. therefore, under those part throttle inputs, your torque converter will NOT be flashing to anywhere near your full stall speed.
However, you also need to keep in mind that very high stall speeds (4,000+RPM) can create more heat that can also be transfered to the transmission and in some applications that can spell reduced transmission longevity. Some guys get around that potential problem by installing very efficient transmission coolers. But for me, I try to keep my street driven cars using stall speeds of 3,500 RPM or less.
About the gears in the rear, you need to know what you currently have, and that's very easy to find out by chocking up the front tires, getting the rear of the car on jack stands, and slipping the shifter in neutral. You then put some white paint or chalk on the drive shaft, and turn the drive wheel one full turn while counting how many revolutions the drive shaft goes through. For instance, 3.5 turns of the drive shaft to every one turn of the wheel would indicate 3.55 gears. A hair over 4 turns would indicate 4.11 gears.
It's important that you know what rear gear ratio you have in there now, because a Small gear ratio change wouldn't even make any noticeable difference in acceleration, and it would therefore be a waste of effort. if you have 3.08 gears, there's no sense going to 3.31's, and if you have 3.31's, there's no sense going to 3.55's. Small gear changes like that aren't going to make much difference in acceleration times (0-60MPH). Particularly in a heavy street car (over 3,200 LBS).
One other thing : if you're going to change the rear gear ratio and you've never done it before, you better do your homework and get the procedure down correctly. If you fail to set-up the ring & pinion gears correctly with the proper amount of backlash,pinion depth, pinion gear pre-load and gear pattern using the marking compound to check it, then there can potentially be catastrophic results when driving down the highway! So if you aren't going to do your homework on that, then leave it to the professionals to do it for you.
BTW, the reason why I suggested a 600 CFM carb if you do decide to get a Holley, is that's usually all that's needed for a street car with a 350cid engine if the redline is no higher than 6,000 RPM. But that depends on the cam you're using too. A lot of guys tend to over-carb their street cars, and performance can suffer as a result. The maximum CFM of air that a 350CID engine can move at 6,000 RPM is 605 if it's naturally aspirated.
