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Making the Mustang daily driverable after modifying

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1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
The harshness got bad when I installed the swaybars, UCA and lca.

Hmm. Well, you've already removed the LCA (I assume you had installed - and then removed - the relocation brackets at the same time as the LCAs) and the poly diff bushing. So that leaves the UCA itself and the mount and the swaybars.

You mentioned the endlinks on the rear bar but you didn't mention the front seat bar links. If they are stock, maybe it's possible that you have too much preload on one or both sides of your bar that is contributing to the harshness?

Can you tell if the harshness when you hit a bump is mainly from your front suspension or rear?
 
While this is getting sorted out I'll offer a fast and quick workaround to immediately make the car more tolerable: remove the rear sway bar. Just take it off and set it aside. Yes, it'll jack up the handling unless you're tuned for it but I guarantee it'll make a difference and it only takes a few minutes to accomplish.
 
The harshness on rough roads feels like it is front and rear.

The LCA are slightly angled downwards towards the front.

Will a higher tire psi make the ride stiffer/abrasive?
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
Higher PSI will slightly increase harshness. It will also increase wear on the center of your tire.

I still think your off-angle LCA is contributing to your problem. Check the underside of your body JUST behind the LCA body mount. If you see some scuffing there it is from your OEM LCA hitting it when your rear suspension is compressed a bit.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
With regards to the lower control arms, they are not hitting the body of the car. Will the BMR relocation brackets any NVH, stiffness? Will they work with factory LCA?
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
I believe the modification required to use the BMR relocation brackets with stock LCAs is to use 2 bolts and nuts instead of the provided bolt with spacer. The stock LCA will hit the bolt with spacer in the upper hole positions. Using two bolts/nuts on either side will leave the center space empty and allow room for the stock LCA.

Make sure you use grade 8, 8.8, or even 10.9 hardware if you go this route.
 
Okay the car has been off the road a nice the last post. While the Coronavirus quarantine is on going I am going to address the posted issues on the Mustang. I just put it on jackstands to address any surface rust underneath.

With regards to the jounce bumper stops. I will post a pic of the eibach ones below. They look to be shorter than the Ford performance ones that come on the gt500.

The front I believe the b6 struts has internal jounce stops, there is nothing under the blue sheath. I've also see a dismantle video of a strut on you tube and you can see the internal bumpstops.IMG_20200328_130252.jpg

So my question is with a higher bumpstop, it should prevent the shock bottoming out, should I buy for Ford performance ones? I'm aware some people cut their bump stops when lowering.
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
There are two things to consider regarding the bumpstops. Height & hardness. The Ford Perf bumpers are softer than the regular bumpers. I have no idea how the Eibachs are. With the Ford bumpers there is a natural place you can cut them off if necessary. It doesn't look like you can do that with the Eibachs. It's hard to tell, especially if the car has been sitting for a while but the bumpstop doesn't look abraded as I would expect if it were hitting the body much.
 
The jounce bumpers have arrived. I'm removing the side and rear roush splitters as they are a pain to clean. New hardware for the factory side skirts are on the way. All of the underneath is cleaned, removed surface rust. The rust was mainly on the sheet metal at the top of the rear end links.

When I installed the endlinks the top bolts were torqued to spec. However if you look at the bushings you can see the metal is pinching the pushing, should I loosen the torq on the nuts?

I also have some fluid film on the way with a 360 degree nozzle to rust proof the underneath and fender wells.

This is going to be a while as I just broke my foot. Once I reinstall everything will come the relocation brackets.

The cheapest option is to keep the track Pack lca and buy che relocation brackets.

The other option to stay with an OEM route is the boss 302s lca and brackets. However as I mentioned in my first post, when it had whiteline lca and brackets the rear diff whine was very loud. I don't want to blow $300 for nothing. I want the absolute minimum nvh.

Another option are the roush lca with rubber bands bushings and maybe boss 302s brackets of they work.
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
I would recommend you make the changes one at a time so you can track the effect on your car. Replacing the rear jounce bumpers is super easy. Do that first and see what it does for your ride.

The CHE brackets are super sturdy. I am using them with the GT500 LCAs. They will lower the axle end of the LCA by 2-3/8". If your axle end of your LCA is anywhere between say, 1" to 1-3/4" higher than the chassis end then the CHE brackets will be great. Measure from ground to the center of the front and rear bolts. You could push it by having them perfectly level (axle end 2 to 2-1/2" higher) but that depends on the level of understeer or oversteer you're comfortable with.

If there is a bigger gap then you'll need something like the BMR or Maximum Motorsports LCA relocation bracket.

@Norm Peterson recently gave this advice to someone who was lowering their car

"Lowering without relocating the LCAs will make the car understeer more. How much more depends on how much lowering vs how much LCA relocating.

That doesn't matter as much to some people as others, and it does depend on how hard the hard cornering gets (slalom and abrupt lane change maneuvers in particular). Some people would notice more understeer right away, others wouldn't notice it no matter how heavy it gets. Most people probably fall somewhere in the middle, a little more toward being less likely to notice."
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
When I installed the endlinks the top bolts were torqued to spec. However if you look at the bushings you can see the metal is pinching the pushing, should I loosen the torq on the nuts?
You're talking about the bolts that attach the rear drop links to the chassis-side brackets, right?

Rather than back off on the torque (which runs the risk of creating a clunk or making an existing clunk worse), I suggest removing these links and checking to make sure that the inner sleeves that run through the poly are no shorter than the poly itself (preferably a tiny bit longer). If the sleeves are shorter, you can file/sand/grind the poly and make those connections function more properly as pivot points.

Steeda rear sta-bar drop links.jpg


Norm
 
Che brackets were installed and the lca are parrarel to the ground. It's hard to notice any improvement, it is still hard on the bumps.

Also is there a way to adjust the panhard bar when the tires protrude the fenders?
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
If only one is protruding then you have to measure how far off. Park the car on a perfectly level surface. Using a weighted string taped above the fender, centered over the hub of the wheel. Measure the difference on difference on either side and then decide how much distance you need to move the axle. It it is 1/2" off then you divide in half and thats the difference you either have to shorten or lengthen the PB. If you have a helper you can use a metal yard stick with a level instead of the string.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Also is there a way to adjust the panhard bar when the tires protrude the fenders?
There is no adjustment in the OE panhard bar, so you will need an aftermarket adjustable PHB.

While shopping for the PHB, note that you will not need to replace the PHB brace (sometimes called an "upper PHB") for street driving or even autocross/HPDE as long as your car is still riding on at least semi-streetable tires.


Norm
 
If only one is protruding then you have to measure how far off. Park the car on a perfectly level surface. Using a weighted string taped above the fender, centered over the hub of the wheel. Measure the difference on difference on either side and then decide how much distance you need to move the axle. It it is 1/2" off then you divide in half and thats the difference you either have to shorten or lengthen the PB. If you have a helper you can use a metal yard stick with a level instead of the string.

That's how I have calculated it before, however the tires are past the fender metal so whatever is weighted does not go straight down, it hangs on the tire, defeating the whole measurement.
 
There is no adjustment in the OE panhard bar, so you will need an aftermarket adjustable PHB.

While shopping for the PHB, note that you will not need to replace the PHB brace (sometimes called an "upper PHB") for street driving or even autocross/HPDE as long as your car is still riding on at least semi-streetable tires.


Norm

I have a whiteline adjustable panhard bar and support brace.
 

Norm Peterson

Corner Barstool Sitter
939
712
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
That's how I have calculated it before, however the tires are past the fender metal so whatever is weighted does not go straight down, it hangs on the tire, defeating the whole measurement.
You'll have to run a level up against the tire and measure between that and the fender with a small scale. If both tires are outside the fenders, you've got a wheel offset or possibly a width issue that needs to be fixed in addition to the axle centering.

If only one tire is outside and the other tire is inside, add the inside amount to the outside amount and divide that by two. Ex., left tire 1" inside with right tire 1/2" outside means the axle needs to move 3/4" to the left (lengthen the PHB by that amount and recheck).


Norm
 

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