I know modding these cars is a bit of an addiction for a lot of people, and one day I suspect I'll be right there with the rest. But for now all I want to try and do is eliminate some of the rear tire/wheel opening gap on my '12 Brembo GT. I do not want to mess with the front. I know there are the 55D springs, but I don't see enough drop in the pictures I've looked at. I was thinking about the Roush 401295 springs and maybe the adjustable panhard bar, and nothing else for now. Anyone else done this?

Thanks for any input.

 

I have always replaced both front and rear with a kit at the same time, that is balanced, or designed/ engineered to work together. I.e. Spring rates, height etc. I do know of some guys that have just replaced the rear springs to roush springs without an issue. If you go too much lower? You will need to watch your rear diff pinion angle and LCA angles and buy an adjustable panhard bar to re center your rear if you go much lower.

Some of the best initial modifications to do? Start with the Lower control arms, sway bars, and adjustable panhard bar. Steeda usually has some great pricing if you buy all at once. Also other great brands with quality products. QA1 or Koni, you can never go wrong with. Definitely the upper control arm, however, it's not very fun to replace that one!

The suspension mods are the best with these cars. You will notice the improvement immediately!

I installed coil overs on both of my rides and love the flexibility to adjust or "dial" the ride in.

Have fun with your project!

 

I initially only did the rear springs when I bought my set of P springs (1" drop). It helped a good bit but I always felt like it could use just a LITTLE more drop, especially after I installed the fronts.

I feel like the front is perfect but the back needs another half inch or so.

I've been looking at these:
http://www.bmrsuspension.com/?page=p...181&superpro=0

Just hard to drop $110 on only rear springs.

 

A lot of kits drop 1" front and 1.5 rear. (Which is not enough!) these rears are set up really high from the Factory...

 

BMR has another set with a higher spring rate, sp067 you might look at. I dropped the rear only in my 2012 3.7 and it ate the middle outta my rear tires. I'd drop the whole car if it was me.

 

Not a 2012 ..... but rather on a '2008 GT ...... I lowered the rear only for the same reason (to eliminate the huge gap in back) with a simple cut of a coil off the top of each rear coil.

https://mustangforums.com/forum/s197...ing-but-4.html

 

I ordered P springs for my '09 GT, and loved the look after doing only the rears. In my case it leveled out the car perfectly. I installed the fronts later on, but went back to stock in the front just because I liked the level look. Guess its whatever looks best to you.

 

Check the pinion angle for correct measurement, lowering only the rear can cause a problem.

 

Like Ledgend said, kinda need to do both. I say do it right, there's a lot to choose from if you just want a mild drop.

 

Changing the front or not changing the front has absolutely no effect on pinion angle.

Only by altering the rear suspension height do you change driveshaft or pinion angles because only then are you moving the rear axle in relation to the transmission.