Mick14

I had the DSC street/occasional track alignment done on my 17 Z06 last year. I did 4 track days after that at the end of the season. I decided I wanted a more aggressive alignment so I went with DSC track/street specs. I looked at what the initial alignment was at before the current alignment and toe in the front and rear had moved significantly. Is the shop not torqueing something enough? Can someone give me advise on what I can check and tighten to make sure it doesn't move again? I am ignorant when it comes to alignment so any pics would be appreciated. TIA. I attached before (you can see how far toe was off) and what they just did.

Mick14

fleming23

Crawl under the car with a paint pen and mark your tie rod adjusters and lock nuts (good idea to mark your eccentric bolts as well). You'll at least know if anything is moving at that point.

Bill Dearborn

I doubt front toe changes without the camber changing or a tie rod bushing failing. Rear toe could change due to toe adjusting cam slipping.

Bill

PeteC7

I've had mine get knocked out of whack twice now (no spins or off track excursions happened). It was very noticeable as the car became almost undriveable. I've heard camber plates can fix things more permanently but I don't want to go that route if I don't have to.

Mark@AMT Motorsport

Depending on the alignment shop, they often get lazy and just hit all those eccentric cams with an impact wrench rather than torquing them to the proper spec. Your alignment shouldn’t be slipping on the street if they’re properly torqued. However if you’re on track and driving fast with sticky tires, those eccentrics are known to move. Adding a camber kit eliminates that and we also recommend Granatelli toe links with our locking hardware to go along with it.

C7 Camber Kit

Adjustable Toe Links

4GS7

I fixed your links.

subieworx

I haven't had mine slip yet (haven't been on track yet) but I definitely have a problem with the limit of what I can achieve with toe in the rear. Need to upgrade to an adjustable arm for sure.

C6_Racer_X

Alignment adjustment "lock" nuts/bolts are one of the few fasteners I intentionally over-tighten (by 10% to 25% usually).

At the front, marking the tie rods is also a really good idea™. Use a paint pen or some cheap nail polish for that marking job. It doesn't hurt to mark everything.

One final thing to note, make sure the tech keeps the alignment heads on the wheels until after all the nuts are torqued at least to spec, and the tie rod lock nuts/jam nuts are fully tightened. That's when you want the final print-out done. Immediately after that, the alignment heads come off and the car is driven out of the shop and returned to you.

If the tech goes back under the car afterward (after locking in and printing the "after" settings) to "tighten everything down fully," you get a printout of what it was during the process, not truly "after."

Also be very suspicious if there's a test drive, and following that, the tech puts it back up on a rack (any rack) and makes further adjustments. Often, they "center the steering wheel" after a test drive without re-installing all the alignment stuff. In theory if you make exactly the same change in opposite directions on each side, it shouldn't change (much). In the real world, it always changes some. Worse still, I've seen guys get it in the wrong direction on one side or the other, and make several attempts to get the steering wheel straight, with the end result not even close to matching the "after" printout.

Mark@AMT Motorsport

That's what I get from posting from my phone. Thanks!

Mick14

Mark, I will be ordering your kits. Just an FYI for everyone, I was reading on here that people said to over torque the eccentric bolts because the recommended 150 lbs would not hold. Well, 180 lbs snapped the bolt. Back to the dealership.

copjsd

My Chevy dealer printed for me the torques specs as follows:

Control arm cam nuts = 125 ft/lbs

Rear toe link nuts = 52 ft/lbs

Considering that our wheels lug nuts are tightened to 100 ft/lbs, many mechanics wouldn't naturally torque control arm cam nuts to 125 pounds unless it was specified by the customer.

And those that tightened to 150 ft/lbs likely stretched the bolt, rendering its clamping force substantially compromised. And of course, do not apply lube to the threads or the bolts will likely snap before the torque is reached.

C6_Racer_X

The 150 ft. lb. "recommendation" on here is the official GM spec of 125 ft. lb. plus 20%. You went beyond that to 180 ft. lb., which is 44% over the GM spec, and I'm not surprised that the bolts snapped trying to reach that setting.
Addressing things in reverse order.

These bolts aren't "torque to yield" bolts. That type of bolt (a lot of head bolts are designed that way) is made of a softer, stretchier alloy. The bolts in the suspension are a much harder alloy and they snap/break when over torqued. I've never seen one permanently stretch (plastic deformation), and I've checked the length before and after on bolts I've torqued to 150 ft. lbs. They do stretch (elastically) when torqued to 125 ft. lbs., and they stretch a bit more (elastically) when over torqued to 150 ft. lbs. They return to their original length when those levels of torque are removed.

You are correct that most techs won't torque them to 125 foot pounds. Most alignment techs won't even bother with using a torque wrench.

Your specs are somewhat correct, but you left some details out, and you left out a few other relevant specs that are important.

The cam nuts on the control arms on the front suspension are indeed specified for 125 ft. lbs. The cam nuts on the rear suspension are different, and each position is unique. The front cam on the rear suspension gets 107 ft. lbs. according to GM, and the rear cam on the rear suspension gets 70 ft. lbs.

My typical "over torque" recommendation for track use is 150 ft. lbs. on the front suspension cams, and 125 ft. lbs. on the front cam at the back, 85 ft. lbs. on the rear cam at the back. Again, those are over GM's specs. Use that recommendation at your own risk. Also, my torque wrench is checked for calibration at least once a year, sometimes more often than that. If you're not sure about the calibration of the wrench, have that checked first.

I don't know the size or material of the bolts used on the aftermarket "camber kits" and what the torque specifications are for the fasteners in those kits. If those kits use the factory bolts, I'd go with the factory specs (or over torque from those specs). If there are replacement bolts and nuts, I'd have to do more research.

copjsd

Thanks for the added information, C6_Racer_X!