Suspension Overhaul

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Galucha

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Got some video footage with my gopro of before and after the install. You'll have to excuse the mess that is my exhaust - have it temporarily rigged up until I can take it to a shop to have tailpipes made.




Its amazing how much the housing moved around with the leaf springs. The coilovers definitely don't have as good a ride quality, but they do a much better job of keeping the rear end rock steady. I've noticed it picked up a bit more acceleration, as more power is going directly to the wheels and not being lost in the leaf springs.

 
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Awesome video comparison. The rear axle angle with the new suspension is rock steady. What about side-to-side axle movement when cornering hard? I couldn't pickup much from the video but in theory you should get some side-to-side movement with the leaf springs.

 

Galucha

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Awesome video comparison. The rear axle angle with the new suspension is rock steady. What about side-to-side axle movement when cornering hard? I couldn't pickup much from the video but in theory you should get some side-to-side movement with the leaf springs.
I'll have to check through my footage and see if I have anything that would show that.

 

Galucha

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Ok I did actually have some footage that kind of illustrates the rear axle movement with the leaf springs. Its hard to tell, but you can see that it was swaying back and forth about 1/2" during hard cornering.




Another thing I noticed is just how bad these tires are for handling. I love the look of the magnum 500s + BFG radial TAs, but they are really holding the car back unfortunately. In the second part of the video you can see how they are rolling over onto the sidewalls. The good news is I found someone on marketplace near me selling a pair of 18x8 American Racing VN510 wheels with michelin pilot sport 4s tires. Picking those up today, and hopefully I'll find a matching pair of rears in the coming weeks.

Screenshot_20210908-142919387 (1).jpg

I estimate that I'll be able to shave about 46lbs of unsprung weight with these wheels/tires as well:

Old wheels/tires

  • 4 15x8 Wheel Vintiques Magnum 500 wheels - 30lbs per wheel
  • 4 235/60R15 BFG Radial TA - 27lbs per tire

New wheels/tires:

  • 2 18x8 VN510 wheels - 20lbs per wheel
  • 2 18x10 VN510 wheels - 23lbs per wheel
  • 2 245/40R18 Michelin tires - 22lbs per tire
  • 2 285/40R18 Michelin tires - 26lbs per tire

Weight before: 228lbs

Weight after: 182lbs

Weight savings: 46lbs

 
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c9zx

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You will love the Michelin tires. Very cool suspension set up you have. Chuck

 
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Ok I did actually have some footage that kind of illustrates the rear axle movement with the leaf springs. Its hard to tell, but you can see that it was swaying back and forth about 1/2" during hard cornering.

Another thing I noticed is just how bad these tires are for handling. I love the look of the magnum 500s + BFG radial TAs, but they are really holding the car back unfortunately. In the second part of the video you can see how they are rolling over onto the sidewalls. The good news is I found someone on marketplace near me selling a pair of 18x8 American Racing VN510 wheels with michelin pilot sport 4s tires. Picking those up today, and hopefully I'll find a matching pair of rears in the coming weeks.

I estimate that I'll be able to shave about 46lbs of unsprung weight with these wheels/tires as well:

Old wheels/tires

  • 4 15x8 Wheel Vintiques Magnum 500 wheels - 30lbs per wheel
  • 4 235/60R15 BFG Radial TA - 27lbs per tire

New wheels/tires:

  • 2 18x8 VN510 wheels - 20lbs per wheel
  • 2 18x10 VN510 wheels - 23lbs per wheel
  • 2 245/40R18 Michelin tires - 22lbs per tire
  • 2 285/40R18 Michelin tires - 26lbs per tire

Weight before: 228lbs

Weight after: 182lbs

Weight savings: 46lbs
Great choice on tires. That's exactly what I transition to from the BFG radials as well. You will think it is a different car with how much more grip you will have. You will have to redo the videos... LOL!

 
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I estimate that I'll be able to shave about 46lbs of unsprung weight with these wheels/tires as well:

Old wheels/tires

  • 4 15x8 Wheel Vintiques Magnum 500 wheels - 30lbs per wheel
  • 4 235/60R15 BFG Radial TA - 27lbs per tire

New wheels/tires:

  • 2 18x8 VN510 wheels - 20lbs per wheel
  • 2 18x10 VN510 wheels - 23lbs per wheel
  • 2 245/40R18 Michelin tires - 22lbs per tire
  • 2 285/40R18 Michelin tires - 26lbs per tire

Weight before: 228lbs

Weight after: 182lbs

Weight savings: 46lbs
I am curious about where you got the tire weight from. From Michelin's website, for the P4S I get:

285/40R18: 29 lbs

245/40R18: 25.7 lbs

https://www.michelinman.com/auto/tires/michelin-pilot-sport-4-s#sizes

 

Galucha

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Galucha

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Test fitted the new wheels and no binding or scrub!

They do seem to fill the fenders out better. With 0 backspacing on these there is about 15/16" between the outside lip of the fender and the rim itself. The old wheels had about 1 1/2" between the rim and fender.

They do NOT clear the SoT upper ball joint, so I suspect that 8" is about as wide a rim as you can go with 18 inch wheels. Maybe 19s or 20s would clear the ball joint allowing you to run wider. I do still have about a half inch of clearance there though, which is plenty.

Will update with rear wheel clearance as soon as I buy them.

PSX_20210909_095242.jpg

PSX_20210909_095741.jpg

PSX_20210909_100314.jpg

Edit: I should mention that I have granada spindles. The upper ball joint clearance may be different with other spindles.

 
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Interesting. I have 18x8 with 0 BS and have no issues with the ball joint, but I have a different suspension. However, the relative position of the ball joint should be more up to the spindle. I am interested in knowing if the Granada spindles are that different since I have considered them. I can measure the tire/fender clearance on mine and can take a picture of the spindle/tire clearance as a reference. I have the slightly wider 255 PS4 tires so it will be interesting to compare. When AutoX I had a slight rubbing between tire and fender in tight turns when the back of the tire points away from the fender. I trimmed about 1/4" along part of the rear half of the fender lip to cure the issue.

Edit: BTW, with the same tire/wheel setup as yours in the rear I added a 1/4" spacer. It could fit a wider spacer but that's as much I can use by keeping at least 10 turns of the wheel lug nut.

 
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Galucha

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Interesting. I have 18x8 with 0 BS and have no issues with the ball joint, but I have a different suspension. However, the relative position of the ball joint should be more up to the spindle. I am interested in knowing if the Granada spindles are that different since I have considered them. I can measure the tire/fender clearance on mine and can take a picture of the spindle/tire clearance as a reference. I have the slightly wider 255 PS4 tires so it will be interesting to compare. When AutoX I had a slight rubbing between tire and fender in tight turns when the back of the tire points away from the fender. I trimmed about 1/4" along part of the rear half of the fender lip to cure the issue.

Edit: BTW, with the same tire/wheel setup as yours in the rear I added a 1/4" spacer. It could fit a wider spacer but that's as much I can use by keeping at least 10 turns of the wheel lug nut.


That is interesting. I'll try to get some measurements on the Granada spindle this afternoon. Curious to see how it compares to the stock mustang disc spindles.

And thanks for the heads up on the spacer for the rear wheels. 

 

Galucha

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Ok here is what I came back with. Not to scale - these are just images I found that I could overlay the measurements on.

Granada Spindle 1.png

1484949680_q.png

 
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Something seems off. My tire is about 1.5" from the outside fender edge. The picture shows about 1 3/4 but the molding is about 1/4". Then, if you see on the ball joint side there is almost a 1" gap.

My wheels are 18x8 with zero BS and my tires are 255/45R18

20210909_224822.jpg

20210909_225517.jpg

 
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Galucha

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Something seems off. My tire is about 1.5" from the outside fender edge. The picture shows about 1 3/4 but the molding is about 1/4". Then, if you see on the ball joint side there is almost a 1" gap.

My wheels are 18x8 with zero BS and my tires are 255/45R18
Ok had to wrap my head around this for a while, but I think I've got it figured out. The only way you could have more clearance than me on BOTH the fender and ball joint side is if:

A - The Granada brake rotor "hat" is thicker than the Wilwood one, which pushes the wheel out further to the fender.

and 

B - The distance from the ball joint to the "stub" that the rotor rides on is narrower on the Granada spindles, which places the wheel closer to the control arms.

PSX_20210910_104955.jpg

Alternatively, the Granada spindles could have more positive camber actually built into their design, which also would pull the wheel closer to the upper ball joint I think. Wouldn't know for sure unless I pull them off and were able to measure all of the angles in detail.

I think that makes sense. I don't have plans on ever running wider than 18x8 on the fronts, so it doesn't really make a difference to me, but it could be some very useful info for someone with a similar Granada setup who is looking to run wide wheels.

 
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