Ok, how is the car on the highway? Are you sitting at a higher RPM when you are in 5th on the highway? I was told not to go with 4.10's because you will eat up more gas on the highway, and you will be sitting at a higher RPM number. So, how is it on the highway?

 

Mustangfan45.....you are reving at about 200-300 more RPMS then with the stock 3.55's in fifth gear...if you have 3.31's I am not sure how much more but its not crazy bad and just do the speed limit when on the highway and save the gas for racing

 

Ok, what about if you put a little more horsepower in the car. Does that change were the RPM's will sit?

 

I was running low 13's, best was a 13.0 w/ the 3.55's. Then I put the 4.10's in. Ran a 1.700 60' and got an 12.8. I don't know how consistant that is because I have notwent back since. Im a big guy so the car is faster than that. Highway is about 250 more rpm at 80.

 

i don't have time slip numbers, but my 4:10's are insane......i love them..like posted before, drive "normal highway speeds" and save the gas for racing....i went from 3:31's to 4:10's and tach a wee bit higher rpms....IMO, you will need some bigger tires and wheels for traction....as far as perfomance mods that change the rpm's while driving,except for a gear change you are kosher....
anyone correct me if i am wrong! go for the 4:10's and never look back!!!!

 

Anybody have an idea at what speed you will shift...stock [3:55] 2nd gear goes to just over 60...what about after gears?

I'm still trying to decide between 3:90's and 4:10's

 

does anyone remember that thread, maybe a month or soago where a guy bought some 4.10s from a dealership for a VERY good price? so good that he thought it was too good to be true? butthey shipped to him just fine and they weren't motives. i can't find it anywhere and i'd like to order from the same place....

 

I've read up to .5 tenths of a second. I dropped .3 tenths off mine but didn't have slicks so I was slipping all over the place.