Buying new gears

[Bird of White]

I currently have 3.23 gears on my bird, but I want either 3.42's or 3.73's. I've heard that 3.73's will kill your gas mileage and hurt top end. On the other side I heard 3.42's don't help enough on low end. Please give me some personal feedback on what you think would be good for me. Also I am looking into getting a torque converter has anyone installed one and what kind of performance gains did you get? Thanks for the info.

[TheBeast]

3.42s matched with a good torque converter will give you nice launches. In fact you could take a stock LS1/LT1 off the line with that setup. 3.73s with a torque converter will give you crazy launches. May be a little too much to have as a "daily driver", but I'm not sure. I know of one guy on here with that setup who could tell you how it is. His board name is like "bluecmaro97" I think.

3.73s might be a little much for a relatively stock 3.4L f-body. If you match some HP mods with them, then they might turn out alright.

[Bird of White]

What kind of torque converter do I need? What is lock up and what about the 1800 rpm or 2200 rpm or 2800 rpm? What does all that stuff mean? Aprreciate the help!

[Blue Jay]

The only ones that will fit in the 3.4 are the Yank and the Vigilante. I have a Yank 3000 and think its a great converter, even though I am having trouble with it now. It is an expensive mod, so if you do it, be sure to do it right. I believe stock stall is around 1500, so your gonna want more than a 1800 stall, you wouldn't even notice a difference. No less than 2500 I would say. If you call Yank you can talk to them, tell them what you have and what kinda of performance you want, and they'll make a suggestion.

[98_Roadster]

I like my 3:73's. My gas milage isn't too bad. About 25MPG on the highway at 75-80MPH. I think that's about what the Z gets. I was getting 32MPG at 80MPH with my 3:08's. I'm more of a stop light to stop light guy anyway so they suit me perfectly. I'm probably going to be doing the converter swap the same time I do the Drive Shaft.
The 3000 stall is a little too much for me. I'll probably go with the a 2400 or so.