Best Gear Ratio 3.73 or 4.10
06-04-2014, 08:43 PM
#12
3rd Gear Member
Join Date: Jun 2006
Location: Providence Forge, VA
Posts: 750
Setting up gears in the 8.8 is an art. I would check around in your area for any Performance shops that specialize in Mustang and talk to them about doing gears. Ford is the last place I would take it. The averages shop tech at a dealership probably hasn't done 3 rear gear changes in his career.
The way the auto in our cars is geared the 3.73's just work better. They make a big difference with normal around town driving. The car really comes alive with more gear. You definitely need a tune, not only for the speedometer but the trans shift points and torque curves need to be modified to get the most out of your new gears. If you don't plan on doing any more mods to the car then a CAI is not needed but if you want the most from what you have, the CAI and a good tune will be worth the money for sure.
The way the auto in our cars is geared the 3.73's just work better. They make a big difference with normal around town driving. The car really comes alive with more gear. You definitely need a tune, not only for the speedometer but the trans shift points and torque curves need to be modified to get the most out of your new gears. If you don't plan on doing any more mods to the car then a CAI is not needed but if you want the most from what you have, the CAI and a good tune will be worth the money for sure.
06-05-2014, 02:37 PM
#13
5th Gear Member
Join Date: Mar 2006
Location: Colorado
Posts: 2,652
I also concur that you should be looking for a gear/transmission or better yet, a performance shop with experience doing installs. Don't take it to the dealership. They don't do many swaps for a reason and that's because it's something that is not just plug and go and takes the right level of experience and knowledge to do it right so you don't end up with a whining rear end.
06-05-2014, 04:29 PM
#14
1st Gear Member
Thread Starter
Join Date: May 2014
Location: IL
Posts: 55
Just talked to a speed shop near me, he has a Cobra he is installing gears in Tuesday and will do mine Wednesday next week for $350
I also concur that you should be looking for a gear/transmission or better yet, a performance shop with experience doing installs. Don't take it to the dealership. They don't do many swaps for a reason and that's because it's something that is not just plug and go and takes the right level of experience and knowledge to do it right so you don't end up with a whining rear end.
06-06-2014, 02:09 PM
#16
5th Gear Member
Join Date: Mar 2006
Location: Colorado
Posts: 2,652
Nice. Make sure you get some friction modifier too. You might have to get that from Ford. Bottle is small and expensive, but it's needed to keep the whining from happening.
06-06-2014, 03:42 PM
#17
1st Gear Member
Join Date: Jun 2011
Location: AZ
Posts: 64
My only caution would be around what your future plans are for mods.
If you plan to go FI and big rwhp/tq numbers your will need to do a lot of suspension work to run 4.10s, otherwise you will not hook up.
In other words, if your plan is to build a car for the strip (new springs, dampers, UCA, LCA, and most importantly WIDE drag radials) then 4.10s are the choice.
If you plan only modest power gains then I defer to my more knowledgeable friends on the forum.
My car would NOT hook up easily with 3.73s on street performance tires. When these wear out I will be upgrading my wheels and tires.
If you plan to go FI and big rwhp/tq numbers your will need to do a lot of suspension work to run 4.10s, otherwise you will not hook up.
In other words, if your plan is to build a car for the strip (new springs, dampers, UCA, LCA, and most importantly WIDE drag radials) then 4.10s are the choice.
If you plan only modest power gains then I defer to my more knowledgeable friends on the forum.
My car would NOT hook up easily with 3.73s on street performance tires. When these wear out I will be upgrading my wheels and tires.
06-07-2014, 07:24 AM
#18
6th Gear Member
Join Date: Feb 2007
Location: state of confusion
Posts: 7,635
What that stuff is for is to keep the limited slip clutch plates sliding smoothly instead of chattering when you're turning (especially slow, tight turns).
Norm
Last edited by Norm Peterson; 06-07-2014 at 07:28 AM. Reason: removed those extra blank lines the site insists on inserting automatically
06-08-2014, 04:47 AM
#19
Join Date: May 2014
Location: AZ
Posts: 2
My feeling exactly, I have a new 2014 manual with the track package, I wouldn't want more gear at all.
06-08-2014, 10:08 AM
#20
BUT....the perfect combo imo is a 4.10 gear with an oversized rear tire diameter of 28" (295/45/18 for example). This will lower the effective gearing combined with the oversized tire to about 3.90, the perfect gearing with this automatic transmission. If ur planning on staying stock in tire diameter (27") stick with the 3.73....hope this helps.
