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Wanting to run 15mm front spacer. What is needed?

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We use the S550 front hubs on the S197 which allows more stud options rather than the direct fit ARP's. Several Customers have converted the front to 14mm for extra capacity especially with some of the 11+" wheels and tires getting stuffed up front. We have a mid-length 14mm stud that safely takes a 15mm spacer basically splits the 1/2" and 1" longer than stock S550 ARP stud.
 

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670
1,061
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Time Attack
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5-10 Years
Bay Area, CA
Having realized that I was talking about S550 parts in an S197 section (oops...) it did occur to me that if the knurl is the same on the studs then S550 studs might just work in S197 hubs. IIRC OP was offering 1/2" ARP studs in S550 hubs back in the early days before longer 14mm studs were available, so it's possible that the studs can interchange. As for wheels, I'm running S197 OEM rims on my GT350 and the rims fit over the fatter lugs just fine. It requires new lug nuts, but it might be an option.

The knurl diameter is different between the two hubs. Tim does offer 1/2" studs for the S550 hub but they are not the same studs that are used in the S197/Ford Racing Hub kit.
 
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1,113
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HPDE
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Philly Metro Area

He said to cut the ARP studs down to stock length. I was looking for a more refined solution that would not leave an uncoated end.

I'll probably go with the stock length Moser studs.

Edit: Moser & Strange wheel studs only seem to be available for the rear with the .625 knurl. Makes sense since that's what they specialize in.

May need to cut the ARPs for the front and coat the cut ends with caliper paint or similar.
 
Last edited:
76
51
Exp. Type
HPDE
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3-5 Years
Dothan, Alabama
After test fitting the apex wheels after alignment I'm gonna need at least a 10mm spacer to clear comfortably. So extended studs and spacers coming soon, and back to the extreme contacts for Sunday.
 
76
51
Exp. Type
HPDE
Exp. Level
3-5 Years
Dothan, Alabama
Forgot to update post. I finally got the ARP extended studs installed, and the 15mm hubcentric spacer I bought from a member. With the camber bolts and some more clearance I was able to pull camber from -1 degree to -2.6 degrees. Hopefully will only have to run on the bolts for a few events if not less before I can pick up some coilovers. The 15mm spacer gave me plenty of room for any kind of suspension compression or movement.

Really love the aggressiveness of the front with everything installed.
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