rear end gears multiply engine torque one more time after the transmission before it gets to your tires. If you drive a manual, you understand that 1st gear has the best acceleration, but it only goes ~40 mph. Then your 5th gear has the worst acceleration, but theoretically lets you hit the highest speeds. Adding 4.10s increases the acceleration because it multiplies the torque more, but it also makes you spin your engine faster, so you wont be able to hit as high of speeds in each transmission gear.

 

4:10's ,,,my favorite mod!!!!!!

 

I went 4.10's... in a street race I wouldn't have any other. The rest of the time people riding in my car complain about something or other since I installed them.

Pro 5.0 makes some good 3.90's. I think those would be the way to go for either FI or N2O. JMO...

 

I think i will have to go with 4.10's... even though i might get a twin screw in the near future, i might also get a turbo which might complement well. With the 4.10's you just cant dump the clutch if your FI right?, so what rpm might you rev to before a race from dead stop

 

With a T/S and 3.55 gears I cant keep the tires from spinning if first.

In a street race from a dig I launch at 2k rpms and feather in the power. I short shift to 2nd and then modulate some more, then go WOT in 3rd.

Honestly if you have traction problems stock then you wont be much faster to 60mph with a SC because you still dont have traction.

That is why tires and suspension mods are just or more important than making power. an extra 100rwhp does nothing if you cant hook up. From a 40 mph roll though, you notice a big difference

 

Short shifting 2nd is definitely a must. Even without a blower if you're banging gears shifting into 2nd just blows the tires away. Alot of fun though haha. 4.10s FTW!!!!

 

What do you mean by banging gears?

I just spoke with the shop i deal with and they said if you plan on going turbo or s/c then 3.73 is about as high as you can go, so i am getting a little discouraged from the 4.10's now. Also from hearing that you cant go WOT until 3rd gear with yoru 3.55. Does it matter that i have 20" wheels i plan on keeping? i just don't know what to pick now i am so confused!! it could be months until i get FI but 4.10's sound fun!! but i do not want to change gears twice...errrr

 

By banging gears I mean, shifting real hard, and real fast. It's speed shifting as opposed to granny shifting.

As far as 4.10s I know alot of people around me with F/I and 4.10s. To get the most out of a centri or turbo 4.10s is almost a must. Roots I wouldn't suggest but plenty of people still do it. Look around the forums, tons of S197 owners have F/I and 4.10s and it works great

 

i have 4.10's and just finished another great performance mod., being the jba long tubes, mac pro chamber with prothane motor mounts. let me tell you what a difference those made! especially the motor mounts. i can spin the tires all the way into third gear and with the LT's i can again now accelerate in fifth gear.

 

To start with ... JMO ONLY and should be taken as such..!!!!

The bottom line is to go/get off the line and not sit and spin.. I almost wore out of set of rear tires practicing this.. (going from a dead stop to 60 MPH) takes practice.. plus the TCS is a big plus and your friend on this one..!!!!! then turn it off when you are in about to hit third gear maybe.. ???? I don't know as I have a auto trans car.. where the practice comes in..


I would have to disagree ( JMO ONLY ) and get 3.73 gears.. as again.. why sit and spin ..???? the other guy is already gone and you are up in smoke.. not much fun eh..????? unless you want to impress your buds and do major burn outs.. but I bet they won't buy you new tires when the time comes.. lol

now if you are not 100% POSITIVE you are not going to get a S/C .. then I would get 4.10's.. you do know a good S/C installed cost a lot of money right..???? ( at least last time I looked they where ) so that is something you MUST THINK about..!!! will you have the funds when the time comes..????? be honest with yourself..!!!!
shlich happens you know..
ie: things come up and the next thing you know.. that S/C fund is spent on something else..

to put your mind as ease.. ask your local PERFORMANCE/Mustang Pro what he would recommend.. what I did.. I have 3.73 Ford gears ( Ford gears a must in my book ) and twin screw S/C.. my guy has always done me right.. as that is ALL he works on.. NOTHING BUT Mustang's all day long... ( I wanted L/T headers.. he talked me out of them.. price per H/P gain ... think about it.. and you will see he is correct...!!!! )

so my advice.. ask him.. not us what to put in your car.. it is YOUR car.. you are the one driving it.. not us.. so let a PRO tell you what to do..!!!!!!

Just my advice for you.. plus.. watch out for things when that bad boy gets squirrelly on ya..!! LOL

best of luck.. and ask a PRO..!!!! you won't regret it.. I promise you.. unless he is a rip off guy..!!!!!

Rex