Springs and Tires (part numbers)

marklboris

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Did not know exactly where to post this so decided to just make a new thread. If this should be moved to an existing thread the moderators can do that.

I don't like the fact that that most Mustang's in general, including the Shelby's, are slightly higher in the front by 1/4" - 1/2" or so than the rear. I personally like to see a more level stance. Therefore I have decided I will be replacing the front springs on my base GT500 with CFTP front springs. The CFTP GT500 sits about 1/2" lower than the base model so I am thinking that should bring the front down on the base to give me a more level stance (might give me every so slightly more negative camber). The rear of the GT500 also has a bit more negative camber than the front does however I am not going to be tracking this car so not interested in adding the adjustable camber plates up front.

Ford Spring part numbers:
KR3Z-5310-A Base front spring (both sides)
KR3Z-5310-B CFTP front spring (both sides)
And in case anyone wanted to replace the rear springs of their base car with CFTP springs,
KR3Z-5560-B Left CFTP rear spring
KR3Z-5560-H Right CFTP rear spring

KR3Z-5A772-A CFTP Rear stabilizer bar
KR3Z-5493-A CFTP bar bushings (2 required)

From the Ford specs, the spring rates for the CFTP model are higher both front and rear (not to mention the rear sway bar is slightly stiffer). I have both springs and while they both look to be the same shape, the CFTP spring is shorter. I feel this will really make the car look better dropping the front a bit and will also stiffen up just a bit with an ever so slight added negative camber.

I have ordered Signature Series SV902 gloss black wheels from Terrance and by the way, he is amazing to work with. Really knows his stuff and definitely knows Mustangs. Unlike many here that want wider wheels, I am happy with 11" for both front and rear. I don't like the look of even slightly stretched tires so will be running 315/30/20's with the 11" wheels all around. Terrance has picked the proper offset so that both front and rear will look the same and the sidewalls of the tires will be just inside the top of the fenders (I hate any poke at all).

As far as tires, while Michelin offers the Pilot Sport 4s in a 315/30/20, they also make the same size for Ford Performance which is what is on the GT500. It has the same exact specs as their standard tire except the Ford Performance model is an acoustic tire (quieter). They run about $10 more per tire than the normal 315/30/20's

Michelin tire part numbers:
20432 Pilot Sport 4s 315/30/20
60304 Pilot Sport 4s 315/30/20 Ford Performance

CFTP spring on left, Base spring on right

IMG_0163.jpeg
 
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Ablaze

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Please post some photos once you get them installed!
 

South40

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Definitely post pictures and your opinion of the ride after the change.
 
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marklboris

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I will post pictures for sure. My hobby is photography so that is never a problem. I doubt there will be a big difference in the ride but I know I will like the look of front being a bit lower.
 

V00D00

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Ford Spring part numbers:
KR3Z-5310-A Base front spring (both sides)
KR3Z-5310-B CFTP front spring (both sides)
And in case anyone wanted to replace the rear springs of their base car with CFTP springs,
KR3Z5560-B Left CFTP rear spring
KR3Z5560-H Right CFTP rear spring

From the Ford specs, the spring rates for the CFTP model are higher both front and rear (not to mention the rear sway bar is slightly stiffer). I have both springs and while they both look to be the same shape, the CFTP spring is shorter. I feel this will really make the car look better dropping the front a bit and will also stiffen up just a bit with an ever so slight added negative camber.

I have ordered Signature Series SV902 gloss black wheels from Terrance and by the way, he is amazing to work with. Really knows his stuff and definitely knows Mustangs. Unlike many here that want wider wheels, I am happy with 11" for both front and rear. I don't like the look of even slightly stretched tires so will be running 315/30/20's with the 11" wheels all around. Terrance has picked the proper offset so that both front and rear will look the same and the sidewalls of the tires will be just inside the top of the fenders (I hate any poke at all).


CFTP spring on left, Base spring on right

IMG_0163.jpeg
This is perfect, i was looking for a spring kit to lower it, but concerned with ride quality. ordering today
 

The Chairman

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Thanks for the spring part numbers. But I must inquire as to the source of the info.
According to various Ford Parts websites, those springs are for a 2019 and earlier GT350R. They don’t have part numbers listed for the 2020 GT500 yet.
Could be the same parts. But with the weight difference, I would be surprised if they are the same springs as a GT500.
 

gfcobra04

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Do you happen to know the sway bar part #?
Thanks
 

V00D00

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Thanks for the spring part numbers. But I must inquire as to the source of the info.
According to various Ford Parts websites, those springs are for a 2019 and earlier GT350R. They don’t have part numbers listed for the 2020 GT500 yet.
Could be the same parts. But with the weight difference, I would be surprised if they are the same springs as a GT500.
^this. i went to purchase and they dont line up. got a direct link?
 

Jmeo

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If you cannot find the answer to this, I can when I get home next week, ask a good friend who works at ford, to get these numbers for us. There is nobody better in my 30 plus years of buying factory Ford parts.
 
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marklboris

marklboris

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Thanks for the spring part numbers. But I must inquire as to the source of the info.
According to various Ford Parts websites, those springs are for a 2019 and earlier GT350R. They don’t have part numbers listed for the 2020 GT500 yet.
I went to my local Ford dealer to get these part numbers and springs. He needed VIN's so I gave him a VIN from a base and CFTP GT500. He said he had to research it and a day later he called me with the part numbers and I ordered them, got them a week later. I will go back down today to let him know these cannot be the proper springs if they are also for the GT350. I agree with you and doubt the GT350 springs will work on the GT500.
 

Epiphany

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I like to disassemble things.
I went through some of this when trying to order the calipers/rotors/knuckles/hubs for the 2020 GT500. There were some pretty knowledgeable Ford Parts guys working on getting me parts numbers and pricing. Some of the numbers weren't right. Same thing with brake lines as the wrong numbers are being provided to Ford Parts and Service departments when inquiries are moved up the ladder. Once again, GT350 hose part numbers were provided and they're wrong - they won't physically fit. This thread falls along the same lines - be cautious at this point.

Because I've gone back and forth on this one, I'm motivated by what I see here and contacted the guy I consider to be the guru and asked him to take a look at it and to order me the CFTP front/rear springs, and the rear bar/bushings as well. I'll report back with what he finds out.
 
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marklboris

marklboris

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Just got back from my dealer. He said they had to look up the build sheet on those VIN's in order to get the part numbers for the springs. He said he believes those part numbers should be correct but is only going by what he was told when he called Ford parts back in Detroit. He also said that those part numbers are not the ones for the 2019 GT350 or 350R. For now I will stick with these numbers until Ford actually comes out with the parts info for these cars at the dealer. I can always return the springs if they are not correct. Hopefully by the time my car arrives, sometime in April I am thinking, we will have more information on GT500 parts.
 

Epiphany

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I like to disassemble things.
Do you happen to know the sway bar part #?
Thanks
Part numbers OP listed were verified, along with the rear bar and RSD. Ordered the springs front and rear along with the rear bar and insulators. Note, I also inquired about the service panel rear seat delete - same part whether CFTP or R. Get this, economies of scale be damned. Even with increased production (used on the CFTP and the R model GT350) Ford bumped the price up with a 100% increase. That one got crossed off the list in hopes that FP once offers it again at a much more reasonable price.

zz 20200206_142729.jpg
 
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marklboris

marklboris

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Thank you for verifying the part numbers I got from my dealer were correct and glad to know I don't need to return the springs.

About the rear stabilizer bar, the part number I got ended in an E instead of A like yours. I was not planning to order one but I wonder why there is a discrepancy? I found that on many of the parts, the base model ended in A and the CFTP ended in B. On there rear springs, the base model ended in A for the left, G for the right while the CFTP ends in B for the left and H for the right.
 

Epiphany

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I like to disassemble things.
If it helps I'll measure the diameter of each bar when everything comes in.

Base rear sway bar FR3Z 5A772 E
Base rear bar bushings F2GZ 5493 C

Thanks for the numbers B!
 
 
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