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Hello all, a little background. I finally got in my Forgestar F14's in C5 fitment 18x9.5 and 19x11. It was my impression that these would easily clear the front C6Z calipers but I am finding that the tolerance is about the thickness of a piece of paper. The guys I bought from have been super helpful and very accomodating. They are getting some high quality 5mm spacers (front only) built for me to give them some room. As is, with the different offset of these wheels I am getting about 8.5 turns of the lug nut. So i figured to be safe I will get some longer wheel studs. I was thinking I would just get a standard replacement aftermarket lug from the autopart store since they thread all the way to the top where the stocks do not. If the overall length is the same this amount will make up the difference from the spacers. Does anyone see an issue with this logic. I know DRM sells some with a similar idea but I was hoping to be able to source something a bit quicker and cheaper. On Advance Auto there is no direct fit option but I found Dorman 610-254 listed elsewhere as the correct fit. Can anyone confirm that my thinking is correct here, happy to hear any better ideas to resolve. Thanks!
Last edited by Mazderati; Mar 2, 2021 at 05:37 PM.
You're 100% fine with 8.5 turns on the stock lugs. With 5mm spacers on the stock rear lugs, I was only getting 6 turns and had no issues or worries for a couple years. General rule of thumb I believe is 8 turns and you're golden.
With that being said, if you want to run extended lugs, you want Dorman 610-323. These are only about 1/4" longer overall, but are threaded to the end, so they're effectively 1/2" longer. I literally just put these in all of my new hubs and have been running them for a couple weeks now. Even with the 5mm spacers though, you will most likely want open ended, or at least extended, lug nuts. I'm still running the same lug nuts as I was before, but they're literally within one turn of bottoming out.
You also don't need anything special for 5mm spacers. Any old ebay or even autozone specials will do. The ones I was running for a couple years were literally universal 5mm non-hubcentric spacers and I kept forgetting to swap them out due to pure laziness. No issues at all.
Thanks for the recommendation, that sounds like the DRM ones that are advertised. The 8.5 turns I am at now is before the spacers so i know i will feel more comfortable with longer studs. I have aftermarket tuner style lug nuts that came with the wheels. I know I'm not even close to bottoming out but when i have the wheel off I will measure how many turns to make sure that i'm not with the new studs. Thanks.
Edit: It looks like 610-323 are closer to 1/2 in longer than stock. Im wondering if the extra thread on the 610-254 is enough, i don't want to worry about bottoming out... hmm
Were you able to get these in the fronts without removing the hub?
Last edited by Mazderati; Mar 2, 2021 at 08:26 PM.
The 610-254 is shorter than stock, unless I read something wrong in the specs: 1.634" (41.5mm) underhead length vs. 53mm underhead length for a stock stud.
The 610-323 or the DRM 1/2" longer are what you want, I think the DRM's are the Dormans..
Awesome, thanks for clearing that up. I couldn't tell if the 610-254 was matching the threaded length or the full length of the stocks. I guess I would have figured it out as soon as i got home from the part store, thanks for saving me the trouble.Sounds like the 610-323 will be the way to go.
Hi. I just ordered same rims, Forgestar F14 18x9,5 offset 49 and 19x11 offset 54. They claim that before mentioned offset clear big brakes. My car is C5 Z06 2002. I am not sure if the situation is different in Z06 ?
I have the same offset and sizes as you. I was told these were a perfect fit and saw many others online saying they worked great. I'm not sure what is unique about my application but I found that i could barely fit a piece of paper between the caliper and back of the rim at the closest point (Front only). I am using C6 GS/Z06 calipers which are very bulky, and I question how close their tolerances are. One side actually rubbed off some of the paint on the rim, but rotated fine. The only non GM piece of the equation is I am running StopTech Discs but i figured their thickness at the hub would be the same as OEM, I guess there could be a small variance. I found many people advocating for these sizes with this setup, I did chat with one other forum member who had the same problem as me though and ended up adding a spacer as well. It is disappointing but life goes on..
Last edited by Mazderati; Mar 3, 2021 at 02:45 PM.
Thanks for the recommendation, that sounds like the DRM ones that are advertised. The 8.5 turns I am at now is before the spacers so i know i will feel more comfortable with longer studs. I have aftermarket tuner style lug nuts that came with the wheels. I know I'm not even close to bottoming out but when i have the wheel off I will measure how many turns to make sure that i'm not with the new studs. Thanks.
Edit: It looks like 610-323 are closer to 1/2 in longer than stock. Im wondering if the extra thread on the 610-254 is enough, i don't want to worry about bottoming out... hmm
Were you able to get these in the fronts without removing the hub?
Sorry missed your post. You can do the fronts without removing the hubs, but the rears have plates blocking access, so you'll need to drill an access hole (which many have done successfully and easily) or remove them. I was doing a complete suspension overhaul, so I installed them in brand new hubs before swapping them in.
The DRM bolts may very well be the Dormans, I'm not sure. All I know is I got the Dormans for about half the price of the DRMs haha. Think I paid around $20 for all of them.
I have the same offset and sizes as you. I was told these were a perfect fit and saw many others online saying they worked great. I'm not sure what is unique about my application but I found that i could barely fit a piece of paper between the caliper and back of the rim at the closest point (Front only). I am using C6 GS/Z06 calipers which are very bulky, and I question how close their tolerances are. One side actually rubbed off some of the paint on the rim, but rotated fine. The only non GM piece of the equation is I am running StopTech Discs but i figured their thickness at the hub would be the same as OEM, I guess there could be a small variance. I found many people advocating for these sizes with this setup, I did chat with one other forum member who had the same problem as me though and ended up adding a spacer as well. It is disappointing but life goes on..
The rotors you're using wouldn't matter. The caliper bracket/caliper mounts to a fixed point on the spindle. Are you running the C6 spindles instead of C5 ones maybe? Unless you're running other non-C5 hardware that could be the culprit, I'd probably chock it up to manufacturing tolerances. But that is very disappointing that they are billed to fit and don't.
Sorry missed your post. You can do the fronts without removing the hubs, but the rears have plates blocking access, so you'll need to drill an access hole (which many have done successfully and easily) or remove them. I was doing a complete suspension overhaul, so I installed them in brand new hubs before swapping them in.
The DRM bolts may very well be the Dormans, I'm not sure. All I know is I got the Dormans for about half the price of the DRMs haha. Think I paid around $20 for all of them.
Thanks I am just doing the fronts so shouldn't be an issue, I ordered 10 of the Dorman shipped from rockauto for $19.
Originally Posted by heggsc5
The rotors you're using wouldn't matter. The caliper bracket/caliper mounts to a fixed point on the spindle. Are you running the C6 spindles instead of C5 ones maybe? Unless you're running other non-C5 hardware that could be the culprit, I'd probably chock it up to manufacturing tolerances. But that is very disappointing that they are billed to fit and don't.
I know it isn't much but I was referring to if the thickness of the rotor where it mounts to the hub was different then it would effectively act as a spacer and push the wheel further away from the hub/caliper. I don't think this is true, just explaining my thought, if anything it should be negligible difference. Everything else that could be a factor is all stock, so I'm not sure. The guys who sold me the wheels have been great and are sending me spacers, it is what it is.
Thanks again!
Last edited by Mazderati; Mar 3, 2021 at 03:33 PM.
I just bought and installed these and did the Z06 brake upgrade as well, and all clear the calipers with no problem, fronts appear to have several mm to spare at the closest point too. FORGESTAR F14 GLOSS BLACK 18X9.5+50MM 5X120.65 CB72.56 SEMI CONCAVE
FORGESTAR F14 GLOSS BLACK 19X11+55MM 5X120.65 CB72.56 SEMI CONCAVE
Are these the offsets you ordered too? And have you confirmed both sides of the caliper mounting surfaces are clean and free of any bits of rust of debris?
Mine are: FORGESTAR F14 18X9.5 5X120.65 49MM 72.56MM GLOSS BLACK SEMI CONCAVE FORGESTAR F14 19X11 5X120.65 53MM 72.56MM GLOSS BLACK DEEP CONCAVE
The brakes fit up very nice, the rotors line up with the pads/caliper perfect so I don't think there is any room for error there. I wonder if they had different factories making these calipers and these are just "thicker" than others. I have noticed that my caliper pins look more inset then others as well, implying the caliper may be a bit thicker. Not sure really.
Mazderati. Where this smallest clearance is and have you measured it ? Wilwood claims that only min 0.08 in clearance will be needed between wheel and caliber. Should it be possible to grind this clearance a little bit from the caliber ? There should be enough material ?
Last edited by Lespaul66; Mar 4, 2021 at 01:11 PM.
You can see my caliper below, there are two black marks on the inside shoulder where the caliper met the inside of the rim. The rim was not getting hung up on the caliper it was just enough to take off some of the paint, this area is the smallest clearance. On the right side it did not contact. I assume that some material could be smoothed out or ground down but right now the clearance is not at .08 ~2mm that you referenced. I am going with a bit longer studs and 5mm spacers just to be safe.
Last edited by Mazderati; Mar 4, 2021 at 01:19 PM.
These C5 Z06 calibers are very bulky. It is very possible that dremel grinding will clear the problem. Difficult to confirm from photo. I dont like spacers, these cause extra forces to construction, but it does not matter if you drive on the road only.
Better solution will be wilwood big brakes which are more slim.
Last edited by Lespaul66; Mar 4, 2021 at 02:50 PM.
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Wheel Studs for Spacers
