If I change the stock gears to maybe a 3.90 or 4.10? I have an 07 pp v6 auto. Real noticable improvement?

http://www.mustangforums.com/m_4782081/tm.htm

They don't make 3.90 gears for our (7.5) rear. There was a noticeable improvement when I put in 3.73s.. so I would think you would really notice 4.10s.



ORIGINAL: vistastang

If I change the stock gears to maybe a 3.90 or 4.10? I have an 07 pp v6 auto. Real noticable improvement?

Simple answer. YES of course! Why wouldn't they? You filling your trunk with concrete or something?

There have been many threads from people using 3:90 gears in their 7.5 inchers. I don't understand why mrsandman said that they don't make them.I've got 3:73's but if I were going to do it again, I'd get 3:90's.

Because I looked everywhere for them.. and I was also told here that no one makes them for the 7.5 (after asking why I could not find them).

It's 3.90. Not 3:90. ;)

http://en.wikipedia.org/wiki/Gear_ratio

ORIGINAL: 68XR7

There have been many threads from people using 3:90 gears in their 7.5 inchers. I don't understand why mrsandman said that they don't make them.I've got 3:73's but if I were going to do it again, I'd get 3:90's.

soooooo, If I am going to wait awhile to supercharge this might be the next best "bang for the buck"? I already have CAI, tuner & duals btw. Any guess on what kind of improvements on 0-60 & 1/4?

Get a Tlok and Gears of your choice

I stand corrected... it is 3.90, sorry, dumb mistake.

ORIGINAL: 68XR7

There have been many threads from people using 3:90 gears in their 7.5 inchers. I don't understand why mrsandman said that they don't make them.I've got 3:73's but if I were going to do it again, I'd get 3:90's.


no one makes 3.90 gears for our 7.5 rears. GM offers them for a 7.5 rear end, but they dont fit (obviously). they do make a 3.90 for the 8.8 though. i looked everywhere for a 3.90 gear before i decided on my 4.10, i wouldve gone that route if i couldve found them.

ORIGINAL: vistastang

If I change the stock gears to maybe a 3.90 or 4.10? I have an 07 pp v6 auto. Real noticable improvement?


With 3.73s, I went from 14.7 to 14.4 seconds in the 1/4.

my gears are finally broken in and my stang really feels like a performance car now. what a tune does for a CAI, gears do for a tune. you really get to experience the powerband much more than before. the acceleration is awesome and i just have 3.73's. i love my setup.

Totally agree.. A the CAI/Tune/3.73 and t-lok combo totally transforms the way this car drives (as it should). The all around experience is much better. A CAI and tune are great.. but adding the t-lok and gears does something special to the overall combination.


ORIGINAL: Sancho805

my gears are finally broken in and my stang really feels like a performance car now. what a tune does for a CAI, gears do for a tune. you really get to experience the powerband much more than before. the acceleration is awesome and i just have 3.73's. i love my setup.

+1! I love my gears, gives me alot more passing power.

When deciding on gears, you need to consider the rear tires you plan to use. If you are keeping the stock size tires (27" dia), then your gearing will be unaffected by the tires. Running a shorter or taller tire will affect your gearing. With my 28" dia DR's and 4.10:1 gears, my final gearing is a calculated 3.95:1. If I went to a 26" dia DR, my effective gearing would be a calculated 4.25:1 ratio. So for those folks thinking of swapping tires/wheels down the road, give some thought to the tire diameter before you decide on gears.

EDIT -
Here's a link to calculating final effective gear ratio with different size tires:

http://www.mustangforums.com/m_2958724/tm.htm

Allow me to do the math for you:

3.31:1 with 27" tires = 3.3100:1
3.31:1 with 26" tires = 3.4373:1
3.31:1 with 28" tires = 3.1917:1

3.55:1 with 27" tires = 3.5500:1
3.55:1 with 26" tires = 3.6865:1
3.55:1 with 28" tires = 3.4232:1

3.73:1 with 27" tires = 3.7300:1
3.73:1 with 26" tires = 3.8734:1
3.73:1 with 28" tires = 3.5967:1

3.90:1 with 27" tires = 3.9000:1
3.90:1 with 26" tires = 4.0500:1
3.90:1 with 28" tires = 3.7607:1

4.10:1 with 27" tires = 4.1000:1
4.10:1 with 26" tires = 4.2576:1
4.10:1 with 28" tires = 3.9535:1

4.30:1 with 27" tires = 4.3000:1
4.30:1 with 26" tires = 4.4653:1
4.30:1 with 28" tires = 4.1464:1

Bill you should put that under the INFO TECH information

Did you have to get the car re-tuned after the gears and t-lok? Or was it just install and go... What about the gauges? Just curious since that's still in my list of "non-cosmetics" to do to my car and get me in more trouble :P

I had mine done at the same time, so I ordered my tune to fit my gears. But you can go in after you upload your tune and change your gear ratio.

ORIGINAL: xyster

Did you have to get the car re-tuned after the gears and t-lok? Or was it just install and go... What about the gauges? Just curious since that's still in my list of "non-cosmetics" to do to my car and get me in more trouble :P


yea...your car has to be tuned to your specific gears otherwise your speedomoter will be significantly off

ORIGINAL: wolfpup

ORIGINAL: xyster

Did you have to get the car re-tuned after the gears and t-lok? Or was it just install and go... What about the gauges? Just curious since that's still in my list of "non-cosmetics" to do to my car and get me in more trouble :P


yea...your car has to be tuned to your specific gears otherwise your speedomoter will be significantly off


With my SCT xcal2 handheld tuner, I have the ability to change the optional parameters for things like different size tires, gear ratios, shift firmness, shift speed, etc. But my tuner (Evolution) didn't lock out those parameters. I've heard that some tuners have locked them, which prevents the user from making those changes. IMO, that stinks. I change my "tire revs per mile" frequently when I swap out my drag radials (28" dia, versus the Pirelli's which are 27" dia).I'd be in a pinch if I couldn't change the parameters each time.

I'm not sure which tuners lock out those features. Can anyone comment on their experience with different tuners?

XCal3 gives the ability, but I think it may be tune dependent, I noticed I could change it on my race tune, but not the canned tunes. I could be wrong though.

My steeda tune didn't even lock the timing. the only thing it locked was the ability to turn tcs off.