Springs and Tires (part numbers)

[biminiLX]

Then yes I agree with you.
Still, I’d probably lean towards a quality aftermarket lowering spring like from a company like Steeda to accomplish this.
I don’t see the CFTP springs as able to do a good enough job, as like I mentioned, to me the front gap is more noticeable on the CFTP cars. In either case, the rear factory gaps are fine.
I hope the CFTP fronts work for you, I look forward to your results.
-J

 

[marklboris]

I have used Steeda springs, sway bars, etc on my Focus RS and have been very happy with them but I want to keep this one mostly with stock Ford parts. While the CFTP springs are a bit lower they also have a slightly higher spring rate which will be nice. I’m not repacking the rear springs but I am replacing the rear bar and bushings (which I just received). Can’t wait to get my car!

 

[biminiLX]

I can understand the desire to stay all Ford. When I plan to do an upgrade, I’ll choose Ford or Ford Performance over aftermarket when possible.
I guess my point is I hope it works for you but I’m not sure if it’ll actually lower the base car much with CFTP springs.
We will see.
Good luck.
-J

 

[marklboris]

I don't see why it wouldn't lower the car since the specs from Ford state the CFTP car is 1/2 lower than the base.
I have both the CFTP springs and base springs and the CFTP springs are shorter. Now I know that really does not
mean much since you can have a shorter spring with a higher spring rate and it may not lower the car as much
but since Ford says it is supposed to be 1/2" lower, I feel it will be.

 

[Epiphany]

From a technical standpoint, Ford lists the difference in ride height between the CFTP and the Base car as being .6" in their Technical Specs pdf.

https://www.google.com/url?sa=t&sou...Vaw3YvaTE0csyv9JWPRdaolRt&cshid=1582349906804

I would be cautious about mixing CFTP and Base springs as they are tuned to a specific ride frequency and (for example) I'm not sure how well the car will pitch or if it will want to porpoise at all even with a relatively small mismatch. It'll be interesting to see how it plays out.

 

[kilobravo]

Thanks for that, Tob.

 

[The Chairman]

My CFTP rear sway bar came in today (thanks Bryan!) The VIN to the BJ green/001 car was used in searching for everything. Note the tag that shows the diameter (25.4mm) correlates to what is listed in the chart in the last post.

Can you re-confirm for us that the -A suffix is the 1” rear sway bar?
The parts system shows FR3Z 5A772 A for EcoBoost cars, and the -E suffix for GT350. The -A is 1/2 the price of the -E version.
I’m about to order the -A version based upon your pictures..... Thanks!

 

[Epiphany]

25.4 mm, or 1". I can measure it for you in the morning if you'd like.

 

[gfcobra04]

My CFTP rear sway bar came in today (thanks Bryan!) The VIN to the BJ green/001 car was used in searching for everything. Note the tag that shows the diameter (25.4mm) correlates to what is listed in the chart in the last post.

Why don’t the green and orange part numbers match?

 

[Epiphany]

"Ford part numbers are divided into two main categories: Engineering Numbers and Service Numbers.

The engineers will design a part and assign it an Engineering part number, which is an alphanumeric reference code used by the assembly plants. When the part is redesigned, the change needs to be noted so the Engineering part number is changed. When the part is released for service it is assigned a Service part number. It is a different number, because how a part is finished and packaged for service is different from its original production counterpart. (It's the number used by your Ford parts man to look for your order. He doesn't want to know about the engineering part number. However, you may need it because the engineering number is the one appearing on many parts.) This allows Ford Parts and Service to track changes affecting interchangeability by modifying the Ford Service part number. The Service part number will not change with the Engineering part number unless the change affects interchangeability. Therefore, the part numbers on the part are generally Engineering numbers while the Service part number will be on the box. There are some exceptions, such as a whole grouping of parts or a kit. Engineering and Service numbers decode the same way. The difference being the fourth character of the prefix."

 

[gfcobra04]

So the green number is the part number and the orange number is engineer’s number?

 

[The Chairman]

25.4 mm, or 1". I can measure it for you in the morning if you'd like.

Thanks. I’ll take your word for it.
I ordered the part. The price is 1/2 other sway bars. So it has me a bit unsure if its the right part number. I guess we’ll see what shows up!

 

[BillyJRacing]

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

There are SIGNIFICANT differences between the off the shelf tire and the FP tire than just "acoustic".

The bespoke FP tire was designed with specific compounding and construction for the vehicle dynamics, weight, power, and demands of the GT500 platform. The off the shelf tire will not handle, respond, feel, or perform as well as the FP tire. If you only drive on the street and never take a spirited drive up a canyon, let alone on a track, the difference may not be noticeable or relevant, but for $40 to have a tire specifically engineered for your car is worth it IMO.

Also a good read:

https://motoiq.com/how-to-properly-select-and-size-tires-for-performance/

 

[Epiphany]

So the green number is the part number and the orange number is engineer’s number?

Yup.

Thanks. I’ll take your word for it.
I ordered the part. The price is 1/2 other sway bars. So it has me a bit unsure if its the right part number. I guess we’ll see what shows up!

I can only speak to what I was directed to order in obtaining the CFTP hardware, which it indeed is.

I went out and verified the diameter of the CFTP bar as well as stock (or "Base" bar).

CFTP rear bar...

Tag from the rear bar on my Base car...

Base rear bar diameter...

If you ordered part KR3Z-5A772-A in hopes of getting the CFTP rear bar you chose the correct number.

 

[marklboris]

I also agree, the KR3Z-5A772-A rear bar is for the CFTP. That was the number my dealer gave me and I just picked up that bar and bushings today. I also ordered the CFTP parts from a VIN from a CFTP car and it was fairly easy for my parts guy at the dealer to find it and the springs I got. Without the VIN he would have had problems finding the parts though as they are not all listed in the parts catalog yet.