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Lowering my 2012 Boss 302

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I filled a bucket list item last summer and picked up a 2012 Boss 302. Love the car, but there were three things that bugged me mildly. First, the grill with the faux intakes needed to go and I found that to be an easy fix. Had that done before the weather turned cool. My next mission was to upgrade the factory 19" wheels, in my thinking the polished rim made the wheel look smaller and diminished the overall profile of the car. I upgraded to 20" wheels, with tires sized to keep the odometer correct but now the amount of "air" in the wheelwell appears excessive. I really did not want to lower the car as I have read many stories of ALL the variables needed to be dealt with when trying to bring the car down and I am not really interested in going to some of those extremes. What is the simple solution to lowering the car to close up that gap without dropping it to the ground? Is it as simple as a set of springs, or will more be necessary regardless?

TIA
 
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Ford Racing P springs are perfect for your needs. Will drop the rear about an inch and the fronts about the same if I recall. You will most likely need an adjustable panhard bar to recenter the axle under the chassis. The P springs ride nicely but are still firmer than OE.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,529
5,243
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
I agree with Champale. If you decide on going with the P springs and adjustable bar, let me know. I have a set of the springs and a Ford adjustable bar in my shop gettin dusty. I also have a set of MM caster camber plate that come off my Boss when I went with coil overs.
 
Hey Guys,



Thanks for all the responses. Lots of good suggestions, and the Ford spring kit seems to be the hot setup. I am not planning on running the car at the track nor will I be doing any drag racing, for me this car is a cruiser (blasphemy!) but I want it to look sharp at the same time. With the current suspension set up the wheelwell gap makes it look like a 4X4 and I really want to eliminate that look. I have no desire to “slam” the car to the ground, and I really don’t want to get involved in a comprehensive suspension/front end/rear axle rebuild just to close that gap. I am trying to keep it simple, and do the least necessary to bring the car down a little and not compromise drivability. Truthfully, I would rather not involve the front end (camber/caster plates/control arms) if I don’t have to, again I am trying to keep the mods to the car at a minimum. If a set of the M-5300-T springs will be sufficient that would be outstanding. If I need to add an adjustable panhard bar just to be safe I am good with that. Again, my interest is looks (with safety as an important consideration), not race capability.



I will post some pictures once we get some weather that cooperates. This one day of sunshine followed by three days of rain is getting tiresome.

TMSBOSS - PM sent
 

JDee

Ancient Racer
1,797
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W2W Racing
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20+ Years
5 miles from Mosport
If you're a boulevardier you don't want the Ford Racing springs unless you like a real rough rider. For what you want to do just go get some aftermarket lowering springs from anyone that has them with stock spring rates. And if you're not going on the track the panhard rod isn't really a worry either.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,529
5,243
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
JDee. I have to disagree on your Panhard bar comment. When you lower the S197 the rear axle tends to be off center because the angle of the bar changes. You correct this with an adjustable bar. On my Boss, you could see the difference, axle not centered when standing behind the vehicle.
 
A boulevardier? I am not sure that is even a word, but I like it!!

Across the board the Ford springs seem to be the preferred ones for what I am attempting to do. I am not expecting a cushy ride, this is a performance car after all!!

I just don't want to get into changing shocks, struts, control arms, adding adjustment plates and the like. I just want to simply drop the car enough to close the gap...
 

TMSBOSS

Spending my pension on car parts and track fees.
7,529
5,243
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
All you will need to buy are springs. Will the rear end be off center, could be. Do you need plates, control arms, shocks, struts and an empty wallet, nope. Unless my wife is logging in then Hell Yes, these parts are Essential.

Good luck on the upgrades.
 

Grant 302

basic and well known psychic
P springs work fine with the stock Boss dampers. On a Boss it will lower the front about 1/2” and about 1” in the back. T springs will lower the back about 1-1/2”.

I’d recommend the adjustable panhard bar, as the lateral shift is pretty obvious if you don’t. If you’re pretty certain it won’t bother you cosmetically, it’s not needed.

Just get an alignment after the springs go in.
 
303
251
Exp. Type
HPDE
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3-5 Years
25 min. to 1½ hrs. from Sonoma (ugh... traffic!)
Is it as simple as a set of springs, or will more be necessary regardless?

Like others have said, an adjustable panhard is a good idea, your axle will move toward the driver's side. Probably just cosmetic but depending on your wheel offset & tire width, could cause some rubbing on bumps.

Other things to consider:

You'll have a bit more negative camber up front, could be a good thing for handling depending how low you go. For street driving, tire wear will increase in the inner edges of front tires though.

Rear Lower Control Arm angle will change, if the front (chassis end) of lower arm is lower than the back (axle) end you will likely experience wheel hop/loss of traction. Relocation brackets will fix this.

Pinion angle may end up out of limits. could cause noise, vibration, U-joint & pinion bearing wear. Adjustable UCA for this if it's a problem
 
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Apparently there is an old thread out there regarding spring ratings, etc. that contains details that may be helpful in my quest. I have no idea where to look for it. Does anyone have an idea where it could be, or can provide a link?

Thanks.
 

Grant 302

basic and well known psychic
It’s in the stickied threads posted at the top of this (S197 tech>suspension) sub-forum:

 
Well guys, thanks to your help I was able to successfully complete my quest to lower my Boss without going crazy. The COVID-19 crisis delayed my final execution, but I finally got the car done and was able to take a few pictures. I went with the Ford parts, M-5300-T Spring kit and the Ford M-4264-A Panhard Bar. Installation was pretty straightforward, a buddy of mine let me use a lift in his shop on a Saturday and other than him compressing the springs for the swap on the front I was able to do most of the job myself. The drop in the front was minimal and the drop in the rear satisfactorily closed the wheel well gap that was driving me crazy! Then to the alignment shop to get the thrust angle right and off we go! Hardest part of the upgrade was finding center caps to fit the 20" Rovos wheels. I ended up sourcing the parts separately, the caps from one vendor and the running pony emblems from another. I am very pleased with the look, and the ride. I really appreciate all the input and guidance in steering me in the right direction.

You will notice that I also changed the look of the front of the car. One thing I never liked about these cars when they first came out in 2012 was the faux ducts for the air and brake intakes. I was able to source a Saleen style grill and light kit which could be installed without any modifications to the front bumper cover. I had someone make me the BOSS 302 decal to fit the grill. I think it looks pretty cool.

Here is the car:

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