3.55's or 3.73's on turbo car.

yes a lower gear numerically will help load the turbo and spool it. I ran 4.10's with my turbo it sucked.

id stick with the 3.73's

Big turbo == big lag.

Taller gears may help with the lag but at the cost of reduced mechanical advantage. It may be a wash in the end.

A shot of nitrous might help to wake that thing up...

you worried about off the line power or just when riding around?

I see alot of guys running 3.55's in their turbo cars.

Where is your powerband at and where do you plan on shifting?

Yes, lower numerical gears will help reduce lag and will allow you to achieve a higher mph in the 1/4 before redline. This all however needs to tie into your combo. If you are shifting at 7k RPM and will only be trapping 130mph in the 1/4 mile, you'll be leaving a lot on the table with some 3.27's (the most commonly used turbo gear). If however you plan on shifting at < 6k RPM with similar trap speeds, a 3.27 will likely be a better gear.

There really won't be a 100% right answer here until you get some solid number in the 1/4 mile and a powerband from the dyno.

Either way, if you plan on running down the strip with some sticky tires a 2-step is an absolute MUST on any turbo'd vehicle. There is no need for nitrous when you are able to launch with 8+psi of boost off the line.