WARNING: DO NOT use 14mm OEM camber bolt in slotted hole
 

*EDIT*
Jump to lesson learned in post #24 below.


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Does the 14mm OEM camber bolt cancel out or add positive camber to any negative camber afforded by a slotted upper hole?

I had stock struts with camber bolts in the upper holes to yield -1.2 camber. I installed ST coilovers with slotted upper holes, used the same 14mm bolts top and bottom, and held the rotors tilted inwards as I torqued down like I did before to maximize negative camber. That yielded 0 and +0.4 camber. I'm going to try swapping in the stock 16mm bolts up top in hopes of getting negative camber.

Can anyone explain how camber came out zero/positive? I'm having difficulty picturing it in my head.

Ride height variation? I believe that as the front is compressed it gains positive camber.

i was able to get -1.2 in the fronts using smaller bolt in the top hole.

^Are you using those with slotted upper holes? Because I also got -1.2 camber when I used OEM camber bolts on my stock struts. But the same set of camber bolts on my new slotted hole coilovers yield 0 camber (the same 14mm bolts x 4 all around).

I've heard that somewhere as well. But IIRC, that's after a certain point of lowering, closer to when the car is slammed. The wheel fitment sticky thread shows negative camber results when lowering the car 1". I'm between 1" to 1.25" lower than stock and two guys are running the same coilovers as mine (ST) with the same out-of-the-box height settings but stock 16mm bolts instead of camber bolts. They get close to -2 camber in front. (TeamZleep and Shutter in this thread: http://www.ft86club.com/forums/showt...t=41432&page=3).

And this guy in another thread posted this regarding coilovers with a slotted top hole without explaining why:

Do the OEM bolts have an eccentric to allow easy adjustment, or is it just a smaller bolt? If they have an eccentric you may have assembled them incorrectly or adjustment the wrong way.

They're not eccentric, just smaller 14mm instead of stock 16mm.

Sounds like something went wonky during the install of the knuckle bolts... a slotted hole + smaller bolts top and bottom should get you a lot of negative camber if done right.

How sure are you that you tilted the knuckle the right way when tightening the bolts? To me it sounds like the bottom bolt slipped inwards as well.

To make your life easier, run the OEM bottom bolt and the smaller top bolt with the slotted strut and you should still get lots of camber.

Another forum seems to concede that a round shaped camber bolt should not go into a slotted hole due to potential slipping: http://m.fitfreak.net/forums/showthr...465&styleid=15

No clear explanation on why but some comments imply it could cause slippage.

The OEM bottom bolt is being used. From the factory, it's 16mm top and 14mm bottom. I ran 14mm top camber bolt and factory 14mm bolt on bottom. I'm certain the bottom hole had no play as it was a tight fit/struggle to slide it in and I saw the rotor tilt in the negative camber direction and had my brother hold it there as I bolted it down. This is my 3rd time installing OEM camber bolts for negative camber. The first 2 times were on stock struts and neg camber was visually apparent (my car then my friend's). It's highly unlikely for me to mess it up the 3rd time. I'm thinking the slots caused the camber bolts to slip.

And I torqued the bolts to the 114 ft-lbs spec in all 3 installations.

Did you install the top hats in the wrong orientation?

The sides of the hole aren't what prevent movement in this system, friction and clamping force do that. so, slotted struts with camber bolts shouldn't slip any more then normal struts and camber bolts.

Sorry to de-thread but where is everyone is buying these from? Subby dealer?

^Yes, the part number is floating around on this forum.Is there a specific orientation for top hats? I didn't notice any difference in clocking.

But the clamping pressure is less on slotted struts due to the decreased clamping area given the same torque spec.

I've used the OEM bolts on the track and over a year, it's not going to slip.

Slotted holes?

No but you just need the inserts. Similar to this. http://vorshlag.smugmug.com/Instruct.../DSC0693-S.jpg

Where can I get that? I coudn't find any info on it for this car/ST coilovers.

I don't have ST coilovers, but there certainly was a difference in my whiteline tophats.

That explains your suggestion. I'm using stock top hats.

Doesn't matter if it slipped guys... the slot is to gain negative camber. If it did slip with weight on the wheels, it would add more negative, not end up positive.

For clarity, are you running the OEM upper mounts? If those are installed the wrong way you'll definitely end up with too much positive camber.

There was no room to go more negative because I maxed it out so if it did slip, positive is the only direction for play. One way to make camber zero/positive is to max it to the other end of the slot and my camber is at zero/positive. I'm going to check the bolt this afternoon.

I'm only reusing the stock top hats. Upper spring perches are included with the coilovers and clocking orientation on those shouldn't matter since they look uniformly shaped all around.

What I meant by slipping was that the only way the weight of the car would make the bolt slip would be on the negative side. I realize that when adjusted for full negative the only place it could move is towards positive, but the weight of the car wouldn't put any force in that direction.

Another question, did you take it in to a shop for an alignment? Is there any chance they moved it back to zero during the alignment on you?

Ya, I gotcha on the weight part.

The before and after alignment show virtually no change. They only adjusted toe. Plus their tools didn't have clearance to jack my car up while it was on the alignment rack nor on the ground so they couldn't take off the tires. I watched them partway through the initial reading and as they adjusted toe.
http://www.ft86club.com/forums/attac...1&d=1388637271

My camber was positive going in. Hope I find out why when I inspect this afternoon.

@wparsons @Calum @post_break

So both my camber bolts DID slip after my first install despite torquing everything to the 114 ft-lbs spec in the max negative position. After I unbolted the top bolt and left the bottom bolt alone today, I saw camber had slipped to max positive:

http://www.ft86club.com/forums/attac...1&d=1388818189

http://www.ft86club.com/forums/attac...1&d=1388818189

The following pic shows the markings left behind from when the bolt slipped toward positive camber under the car's weight. Yes, it goes toward positive camber when the suspension is loaded and negative camber when unloaded which is why I saw the rotor slide toward negative camber when the car was jacked up in the air. That characteristic might hold true only when the *top bolt is LOOSER than bottom* (as was apparently the case with my camber bolt due to less clamping pressure) and may not necessarily be true when both bolts are equally loose. I replaced the 14mm camber bolt with the 16mm stock bolt shown here positioned for max negative camber.

http://www.ft86club.com/forums/attac...1&d=1388818189

The bolts didn't slip on the 30 minute drive to the alignment shop this time and front camber came out to -2.0/-1.7.

"Yes, it goes toward positive camber when the suspension is loaded and negative camber when unloaded"

Sounds familiar. ;)

Haha yes, seems to be but this may be a special case. One bolt was looser (clamping with less pressure) which caused the other bolt to act as a pivot which may have flipped the tendency to the opposite of what it would normally be.

But when we talk about ride height (as you initially suggested) and not compression (not sure if they can be used interchangeably), @DarrenDriven has found lowering adds negative camber (rear moreso than front) and my alignment shop suggested lowering as one way to add negative camber and even out my cross camber (since my bolts are already maxed out).

Glad to see you got this figured out!

It looks like a layer of powder coating was removed. That layer missing would have lowered the clamping force. Was it missing from both holes, on both sides?

Edit, it also looks like the side of the hole is mushroomed, that wouldn't have happened if the bolts was torqued.

It's the other way around. Slipping caused some paint to scrape. I bought these coilovers brand new and there was no paint missing when I first installed them. And if some paint were initially missing, the bolt/nut would just clamp down a few microns closer. 114 ft-lbs is still 114 ft-lbs.

As I stated multiple times, all bolts were torqued to their rated spec. Any tighter poses the risks of snapping or cross-threading. The problem was a shrunken bolt should not be used in an enlarged hole.

I fail to see how a smaller bolt and oval hole has any effect on this since the head of the bolt is still the same size and that is what is applying the clamping force, not the diameter of the bolt itself.

If you could make one strong enough, a 1mm bolt with the same size heads would apply the same clamping force as stock through either a round or oval hole.

I want to emphasize that I torqued everything to spec the first time, no question. I even had to take a breaker bar to the [already slipped] camber bolts because they were still on tight... right around 114 ft-lbs.

Look back at post #8 and the end of post #4 from this thread. I don't think those warnings were pulled out of their ass nor based on theory but reality. Notice the correlation between what they say and what happened to me. Actual result trumps the hypothetical. Not sure what's left to argue.

Did you use smaller bolts on both the upper and lower? Sorry if you said this already, I just couldn't tell. Sorry I can't help with locating the insert, I've seen them before included with other coils. Essentially turning a smaller bolt into an eccentric bolt.

Lower hole can only use the smaller 14mm bolt in all cases. Upper hole comes stock with a larger 16mm shoulder bolt. A smaller 14mm OEM "camber bolt" can be used in place of the 16mm bolt in the upper hole and happens to have the same part number as the 14mm lower bolt. I used the smaller bolts on the upper holes initially, and they slipped. Swapped the stock 16mm shoulder bolts back into the upper holes, and they're holding up fine.

Just an update on the mushroom comment: I bought new nuts and installed them today (service manual recommends replacing with new nuts everytime they are removed) just in case reusing the old ones might have caused slippage. The old nuts were still holding in the max negative position when I removed them but I replaced them anyway and inspected the mushrooming. It isn't truly mushroomed; the thread of the bolt just bites into the metal leaving an indentation at the surface. Past the surface, the actual slot itself isn't mushroomed (though the illusion is there).

In case you're curious, I used a set of H&R Triple C 14mm camber bolts (leftover from my WRX days) on the bottom strut slot. I was able to get -1.1/-1.2 camber. Technically you can get more camber if you have camber bolts on top and bottom, with the bottom set at max camber, you adjust the top camber bolt for more.

Thanks for posting this and saving us potential headaches. Have the stock bolts stayed locked in for good now?

I'm in this same scenario. Probably sticking with the 16MM in the top slotted hole on the V3's.


My question is, -2 possible with the slotted top hole on the V3's or am I going to need bottom bolts for a tad bit more?

There are plenty of us running 14mm OEM crash bolts in slotted upper strut holes, in fact RCE even recommended this for people running OEM top hats to get max negative camber.

I am running 14mm OEM crash bolts in the slotted upper strut hole on my RCE T2s, have about 500 track miles on the setup, and not one bit of slip.

Yeah, they're still in the same position with the stock bolts.
I got -2 left/-1.7 right with this.
What value did you torque to? I read someone did 130 ft-lbs which probably works. There are other ways to make the 14mm bolt work such as inserting a custom fabbed slug insert in the slot or using special washers with teeth. My coilover instructions say to torque to the manufacturer's spec (114 ft-lbs) so that's what I did.

I'll probably pick some up at the dealership. Hard to pass up when they're cheap. Should be able to fine adjust -2.0 on a 14MM upper crash bolt in the slotted hole.