Automatics with 3:73's

[kmad61]

I just got 3:73's installed in my car and was confused about the car not spinning bad on hard launch.From a stop with tc off I will chirp a little and hook up.I was thinking that I would be spinning off the line pretty good,but these cars must hook up good.My best times are with tc on and just nailing it.
For all you auto guys w/3:73's.what happens when you stomp it to the floor from a dead stop with tc off ??????

 

[lenko]

I just got 3:73's installed in my car and was confused about the car not spinning bad on hard launch.From a stop with tc off I will chirp a little and hook up.I was thinking that I would be spinning off the line pretty good,but these cars must hook up good.My best times are with tc on and just nailing it.
For all you auto guys w/3:73's.what happens when you stomp it to the floor from a dead stop with tc off ??????

Mine's pretty well like yours and I was surprised too. Little spin and lots of go. Sure doesn't stay in first very long but gets rubber shifting all gears. Upped all my shift points by +7 mph at all shifts. Speedo reset by tuner.

C&L, Xcal2, Brenspeed 91 octane tune, 3:73 gears, udps, delete plates, Cobra ft, plenum cover and Homelink mirror -temp and compass.

 

[WANNA_BE_GT]

Is anyone here running 4.10's with their autos? Does anyone have a gear calculator for the new mustang autos?

 

[Five Oh Brian]

I have 4.10's in my 07 GT Coupe Automatic. Traction was good on the factory tires at the local dragstrip with the factory torque converter which only stalls to about 2200 rpm's.

However, with the addition of a 3800 rpm stall converter, traction is terrible as the car launches violently with that much stall. I'll be at the dragstrip tomorrow night with drag radials to finally see how much improvement that stall converter has given me beyond just the 4.10's alone.

 

[kooldawg6]

I am running the auto with 4.10s. Makes for a very spirited ride indeed. With a good tune(eliminating the trottle lag), the launch will seem to give you whiplash if you're not prepared for it The factory torque converter doesn't allow for stellar off idle burnouts, while applying the brake, raise the revs to around 1500 then stomp it as you release the brake...then it spins pretty good.

 

[speed1972]

so I'm curious, been looking at doing gears in my wife's auto. She wants some umph added to it without going overboard. I won't be changing the stock converter, so would you recommend 3.73 or 4.10?

Has anyone seen how much 1/4 times improved with these changes?
LB