I'm not using a T56...but i have some experience with a T-5 World Class. The problem with the T-5 is that the first gear is useless except for parades and doing burnouts across intersections. I run a 3.70 gear in the differential and if I start out in 2nd gear the car leaps off the line like an electric car...the engine is a Ford 5.0HO from a 1989 Mustang GT that has been converted to carb. As for road use the T-5 has a very tall overdrive (I think it's a 0.63 gear) and that high gear combined with the 3.70 in the differential puts the engine right at the low end of the power band at highway speeds.
I hope to find a 1/8 mile dragstrip sometime to compare 60 foot times between 1st gear and 2nd gear starts...I bet the 2nd gear starts beat 1st gear by a significant amount, as I lose time to tire spin and have to shift if I start out in 1st, but in 2nd the car hooks up with little spin and there's no need to shift, as I'm already at the end of 60' about when the engine hits the redline.
So...the best advice I could give would be to use one of the calculators and pick a rear end gear ratio that provides a highway speed RPM slightly higher than the lower limit of your cam's power band, Tire size plays an important part in that.
Cheers!
Dugly
