I was wondering why do automatic Mach 1's redline around 5800rpm's and 5 speed's redline around 6800rpm's? I dont get it..

 

Not sure. But could have to do with the 5 speeds having forged cranks. I am not positive though.

 

i'm pretty sure the motors are the same.... I don't see why they should redline at different rpms, maybe you saw one with different gauges?

 

Nope. The 5 speeds do have a forged crank. I am positive about that.

I am just not positve about that being the reason for the higher redline.

 

Good question. Maybe the trannys themselves can't handle that much spinning?

 

my only guess would be because of the cast iron crank (GT crank) in the Mach 1 autos. Something about ford would have had to redesigned it to an 8bolt pattern to mate to the 4R70W (ford cutting corners again, whod-a-thunk?? either way.. a stick is the way to go for a street car. An auto is the way to go if you will drop your life savings and turn it into a 10 second or less drag car.