ren274u

I have a auto and looking for gears, im gonna get ford racing, but im not sure about 3.73 or 4.10, u auto guys what are your rpms at 80mph? any reccomendations? thanks

RemainVayne

Go for the compromise and get 3.90s

tradetheoex

I have the 4.10s in my auto and I wouldn't go taller. I would get the 4.10s, and if your gonna race it at all, get the 4.30s. The Ended up getting a shorter tire for drag racing because the car responded so well to a shorter gear.

LL05GT

I have 4:10's in my auto and I am completly happy with them. Not sure of rpms as my speedometer is still off. However, I can hardly notice a difference and my mpg has not changed at all. I do a lot of city driving and a fair amount of freeway as well, get 4:10's you won't regret it, I feel 3:73's are a waste of your money. Just my opinion though.

spyder7724

i have 3.73's in my auto and they worked out fine. i do run a 26" tall tire at the track so it allows me to run a higher gear. if i did it over again i would get 4.11 or 3.90's though. mileage= no noticable change. the auto's have 3.31 stock so jumping to 3.73 is about the same jump as the stick cars going from 3.55 to 4.11. still i think 3.90's are the perfect gear for an auto.

ren274u

any estimates on how much the 4.10 will help my et? so far just intake and tuner running 13.6

spyder7724

heres what i ran in progression of mods:
13.70=tuner 60'=2.04
13.58=tuner+aluminum d/shaft 60'=2.00
13.30=tuner+gears+d/shaft 60'=1.98
13.08=tuner +cai+gears+d/shaft+torque converter+lower pulley+e-h2o pump 60'=1.84! (i did not have a dyno tune on it for the converter at that time so it's going to run much faster next time out!)
all runs on stock rubber!

i think you will run 13.20's maybe some teens if air is good but who knows it may like the 4.11's and run like a raped ape 12.90's are possible.[8D]

ren274u

man i like your car spyder. ill probably go with 4.10 frpp. and some bmr lower control arms. I should have it all by next month. ill see the difference at the track then, thanks for the help.

spyder7724

thanks,my rpms at 80 are 2600. man these cars are great. never dreamed a car with just a few mods could run low 13's and still cruise nice at 80mph...oh yeah and get 22mpg on the highway and 17 in the city.

ren274u

I found this calc on another site. calc Its very accurate. 4:10s will but my rpms at 80 around 2900, thats a little too high, im not sure. maybe i should just drive slower? lol. 3.73's 3.90's 4:10's will there be a big difference in 1/4 tile between the three?