3.27s:
1st gear @ 5900rpms = 40mph
2nd gear @ 5900rpms = 69mph
4.10s:
1st gear @ 5900rpms = 32mph
2nd gear @ 5900rpms = 55mph
The biggest advantage of the 4.10s over the 3.27s is in first gear. You can 60ft the car a whole lot better. But once you get rolling, the gearing advantage becomes less and less with each shift. The tranny gears are 3.37 1st, 1.99 2nd, 1.33 3rd, 1.00 4th.
If you screw up the launch and spin 1st, they will not help you much at all. But if you hook it up, they could help .1 - .2 in the 60ft and .2 - .4 in the 1/4 ET.