[GTSilver]

i've gottan '02 auto gt. i'm gonna put a 4.10 rear....will that cut off my top end speed? i've heard stories bout only bein able to hit 110-115mph. is this true?

[MikeyS281]

No it isn't true, you will be able to do every bit of 135-145 no problem!

[00Stangpede]

mine topped out at 145mph with the 4.10

[Shaun03GT]

Mines a 5speed. I hit 140mph and it was still pulling.

For 5 speeds, the end of 4th at 6000rpm with 4.10's is 111mph. Then overdrive.

[00mustang00]

im putting 4.10s in pretty soon and i knew the top end would take a hit but seriously on normal roads in normal conditions your never gonna go that fast.

[wrr1020]

I really wanna do 4.10's also, i have an auto and commute to school 2-3 days a week and average around 75-80 mph, might take a hit on my gas mileage.

[carnut59]

did 125 and still had more. did that by a state trooper.

[Scott2001GT]

Originally Posted by MikeyS281 No it isn't true, you will be able to do every bit of 135-145 no problem!

in 4th...I would NOT suggest doing that at all!

Originally Posted by wrr1020 I really wanna do 4.10's also, i have an auto and commute to school 2-3 days a week and average around 75-80 mph, might take a hit on my gas mileage.

at 80mph you will be running 3k rpm's. Gas milage will suffer a little but well worth performance IMO.

[04N20GT]

Originally Posted by wrr1020 I really wanna do 4.10's also, i have an auto and commute to school 2-3 days a week and average around 75-80 mph, might take a hit on my gas mileage.

I drive my car a round trip of at least 80 miles when I take it to work on the highway. I have 3.90's in it, and drive between 75-80 the whole way. at 80mph, I am at about 2600rpm. I would say 78-79 puts it at 2500 straight up, so I am guesstimating at 80mph.

The last time I checked my gas milage(doing strictly highway, from work to home, and very little in between) I got just over 20mpg(20.3mpg)

I don't really know if I personaly would notice a difference between 4.10's and 3.90's cause they are so close, but just being able to see the tach in front of you, you would deffinately notice the difference.

[carnut59]

i average 19 mpg

[GTermi]

i did 145 and thats where it almost topped out

[Eagle2000GT]

Different types of commutes seem to show different gas mileage results when gears are installed. I drive 500 miles per week on basically the same commute. It is a combination of county, highway, interstate and city roads. With a few bolt ons (cat-backs and UDPs) I got 23 mpg. After the supercharger was installed I got 22 mpg. After the 3.73 gears were installed I got 20 mpg. If gas were to go to $4 per gallon the difference between 22 mpg and 20 mpg is about $10 per week.

I have heard that if you do a lot of city driving gas mileage can actually go up with 4.10 because you are just driving in the next higher gear.

[slikirish]

Mine is all city. Was 17 MPG when I first got it, 17 MPG after gears, 17 MPG after CAI, and 17 MPG after tune.

[Ke^in]

Originally Posted by GTSilver i've gottan '02 auto gt. i'm gonna put a 4.10 rear....will that cut off my top end speed? i've heard stories bout only bein able to hit 110-115mph. is this true?

110-115 tops in 4th gear. Yes, that is true. It's one reason to go 373s if it's a daily.

Then again, how often do you go that fast?

[Ke^in]

Originally Posted by MikeyS281 No it isn't true, you will be able to do every bit of 135-145 no problem!

In 4th? no. You'll have to shift to 5th gear to hit those numbers.

And gas miledge is one thing that pisses me off about these cars.

A 02 LS1 WS6 can get 24+ MPG in the city. Why can't a 4.7?

[Scott2001GT]

why this turn into a 5 speed 4:10 thread. dude was wondering about a auto...

[JRCEngineering]

Im Also interested in the answer. I do have some input though. A mach we worked on had 4.56s and a 100 shot raced one of my cars and pulled with me untill around 130- 140 . Sounded like he was taching out i counted 5 shifted (I think , we were doing 140 i so paying attention to his car was not my main priority).I just bought a 2000 Gt bone stock decently low miles for 2600 in mint condition. Not a ford guy by any means but 2600 is to cheap not to be

The automatic will def make things worse on you in the long run for speed.

[GTRACER88]

The auto transmission will handle 220 rwhp at WOT... Top speed is way over 115 mph.. come on guys... My car will continue to pull past 130... im an auto..

[JRCEngineering]

Originally Posted by Ke^in In 4th? no. You'll have to shift to 5th gear to hit those numbers. And gas miledge is one thing that pisses me off about these cars. A 02 LS1 WS6 can get 24+ MPG in the city. Why can't a 4.7?

Well a ws6 has a 6 spd First off. The final drive ratio on a standard ws6 is usually 3.23s. Also the transmission gear ratio on a Ws6 are smaller so it seems like the final drive ratio is even smaller. Not to mention there are lower and more aerodynamic and just overall engineered a whole lot better.

Ive had my mustang for about 3 days now and notice a huge difference in cruising speeds and gear length . New to mustangs but not new to racing.

[GTermi]

Originally Posted by JRCEngineering Well a ws6 has a 6 spd First off. The final drive ratio on a standard ws6 is usually 3.23s. Also the transmission gear ratio on a Ws6 are smaller so it seems like the final drive ratio is even smaller. Not to mention there are lower and more aerodynamic and just overall engineered a whole lot better. Ive had my mustang for about 3 days now and notice a huge difference in cruising speeds and gear length . New to mustangs but not new to racing.

well u have to realize that LS1s arent 4.6s. To make a LS fast u can do heads, cam, high comp pistons and bigger motors. now a 4.6 you cant really just build the motor and ur fast. u build the motor so u can spray the hell out of it or put a blower on it. theyre just two different setups.