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

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76
51
Exp. Type
HPDE
Exp. Level
3-5 Years
Dothan, Alabama
I just purchased some 18x10 et 43 apex ec-7 wheels and I just installed some eibach camber bolts to get some more camber up front. I want to run a 15mm spacer upfront to make sure clearance from the strut is okay. What spacer's have you guys ran up front with or without extended studs. Just trying to see if I need to pull the trigger on studs now or not.

This is kind of last minute as I have an event next week. Not sure if I would have enough time to install extended studs for the spacers.
 
76
51
Exp. Type
HPDE
Exp. Level
3-5 Years
Dothan, Alabama
Haven't ordered anything. Installed the camber bolts and getting an alignment Wednesday with the new bolts. Test fit the apex wheels with the bolts near neutral position but more towards possitive and was awfully close to the strut. Once it's aligned I'm gonna test fit the apex wheels again and see how close I am. I was just basing the spacer size off my forgestars I've been running. Really was hoping for a bunch of feedback from you guys haha.
 
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1,243
In the V6L
The minimum thread engagement that I'm prepared to tolerate for a 14mm lug is 20mm, and a 7mm spacer will have you at 19.6mm, so 7mm is the thickest you should go with without changing lugs.

As an aside, the front lugs are 6.6mm longer than the rear lugs, so there's no room for spacers at the rear without changing to longer lugs. I've rebuilt my rear hubs with OEM front wheel studs just so I can run a 7mm spacer back there.
 

Grant 302

basic and well known psychic
The minimum thread engagement that I'm prepared to tolerate for a 14mm lug is 20mm, and a 7mm spacer will have you at 19.6mm, so 7mm is the thickest you should go with without changing lugs.

As an aside, the front lugs are 6.6mm longer than the rear lugs, so there's no room for spacers at the rear without changing to longer lugs. I've rebuilt my rear hubs with OEM front wheel studs just so I can run a 7mm spacer back there.
That sounds like S550 measurements?

Is this sarcasm? I thought we were trying to be helpful.
I think he was just expecting more of a response. Not many have used camber bolts, OEM studs and spacers as the OP intends.

..........

As someone who has used them both on stock S197 front hubs, I still say 3-5mm tops. Index a lug nut and confirm for yourself that you're getting 10+ full turns of engagement with whatever spacer you do run.
 
The stock wheel studs on the S197 cars are soft and can break. I highly recommend using ARP wheel studs and get the long ones and you can use up to a 25mm spacer up front. This is even more critical if you’re running R comps or slicks.
 
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In the V6L
That sounds like S550 measurements?...

2016 GT350 TP measurements. They might have changed for later MY's, but mine are as indicated. I think the rear hubs are just plain vanilla S550 hubs but the fronts are a triumph of parts-bin engineering. They're a hybrid of an SUV hub (unknown model) and Lincoln studs (don't know which model but it's a Lincoln the part number).
 

Apex Wheels

Race Proven, Street Approved
Supporting Vendor
670
1,061
Exp. Type
Time Attack
Exp. Level
5-10 Years
Bay Area, CA
I don't recommend people run over a 5mm spacer on the stock S197 wheel studs. The better option of course is to run ARP studs and then you can go up to a 28mm or so spacer.

Also careful with the camber bolts, they have a lower clamping force than the stock spindle bolts do. I can understand when/why people use them, so just be careful and keep an eye on them.

What tire and size are you planning to run?

- Cory
 
76
51
Exp. Type
HPDE
Exp. Level
3-5 Years
Dothan, Alabama
Is this sarcasm? I thought we were trying to be helpful.

I made this post to see what everyone is running with success. I don't have a dead set plan yet. I posted what I had available, and I'm looking for the best route. I appreciate all the replies, and I'm definitely not just shrugging them off. Sorry for the misunderstanding.

I don't recommend people run over a 5mm spacer on the stock S197 wheel studs. The better option of course is to run ARP studs and then you can go up to a 28mm or so spacer.

Also careful with the camber bolts, they have a lower clamping force than the stock spindle bolts do. I can understand when/why people use them, so just be careful and keep an eye on them.

What tire and size are you planning to run?

- Cory

I'm just running these bolts to squeeze some camber in the few events I'm going to run before moving to coilovers. Figured this would be a decent way not to blow money on cc plates just to turn around and buy coils with cc plates already installed.

I'm gonna be running the suggested tire size on y'alls webpage(275/35/18). Just figured with the camber bolts would bring a clearance issue after my first test fit before alignment. Definitely looking at wheel studs for piece of mind if a spacer comes into the picture.
 

Apex Wheels

Race Proven, Street Approved
Supporting Vendor
670
1,061
Exp. Type
Time Attack
Exp. Level
5-10 Years
Bay Area, CA
I'm just running these bolts to squeeze some camber in the few events I'm going to run before moving to coilovers. Figured this would be a decent way not to blow money on cc plates just to turn around and buy coils with cc plates already installed.

I'm gonna be running the suggested tire size on y'alls webpage(275/35/18). Just figured with the camber bolts would bring a clearance issue after my first test fit before alignment. Definitely looking at wheel studs for piece of mind if a spacer comes into the picture.

Gotcha, yeah that's totally understandable. Dial in some camber, run a 5mm spacer, and go on with your day. Totally fine to do.

Also the 1/2" longer ARP studs are only available for S550 knurl diameters in the M14x1.5 thread pitch. Since the hubs are interchangeable between S197 and S550, you could pick up some S550 hubs (they're cheap) and install the 1/2" longer studs, ARP part number 100-7732.

For those of us that don't need longer studs (can't reword it any better...), are the stock length studs sold by Moser or Strange any better than the Ford studs?

Yes the Strange and Moser studs are noticeably tougher than the oem studs. I run Strange S/S axles in my car and with their 3" screw-in set I have zero complaints and have been very happy.

- Cory
 
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In the V6L
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.
 

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