2wd is faster but only by a hair, and only if track prep with traction promoter is perfect and track temps are not too cold.
If my first pass spins, I use 4wd auto (AWD) not 4Hi, for a better full throttle launch the following run.
The slightest rear tire chirp makes the e-clutch in the transfer case engage the front driveshaft to get me out of the hole and she squats like a monster truck and jumps out of the hole like a jack rabbit.
the front driveshaft disengages after launch so its not a full on 4WD run, that would be 2 tenths slower in 4WD lock (Hi).
THE ONLY way around Factory Torque Management programmed into a TCM to protect your transmission, is with an aftermarket Torque Converter with a higher stall. Trust me!
Launching at 3000rpm, almost at my peak Torque (3600), is 100% better than bogging the engine off the line at 2000.
its all about getting into the powerband as quick as possible without TM interfering.
Anyone who drives a stick knows if your rev's are too low you bog. Rev it higher when you dump the clutch and you are into the powerband quicker
I used go 2.4xx 60' , and down I'm down to 1.8's
Pre-launch rake vs post launch Squat
That's Significant Torque increase, that factory TM cant touch because its way beyond 2000 rpm before I've even left the line
a lower gear ratio in 1st will only help so much if the computer wont release all the HP and Torque past your stock torque converter because of TM.
also, More gears to shift through would most certainly not get my ET's down, LOL!
Everyone at the strip knows the 2 speed Powerglide is the king!
Here's my very first time slip for my 10' Hemi Ram, from July 2010.....
...(left lane) Stock converter, 2.402 60 footer BRUTAL! compared to my new Edge at high 1.8's low 1.9's