How fast can yall go with the 48re in first? How bout second or third?

 

I don't know why you would want to do this. But since I am an insomniac and have nothing better to do:
Assuming you have 3.73 rear gears, and the stock 265/70r17 tires, and a redline of 3200 rpm:
in first gear: 32.9mph
in second: 55.59mph
in 3rd: 80.61mph
in OD: 116.82mph

Heres my math for you all to check over:
3200rpm*60min/hr*(1/gear ratio)*1/diff ratio)*miles/revolution=miles/hr

(miles/rev=Diameter*Pi*63360in/mile)

 

cool is that 47re or 48re?

 

I did the calcs with the gear ratios for the 48re

 

If you only need to go fast once, on the cheap, any Ram will hit just the other side of 120 mph if the bridge is high enough

 

good point or/and I can shift it to 1st on the column in mid air.

 

Yeah, but get your buddy to do it with his ride first!

... so you can post results.