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Eccentric Bolts vs Camber Plates

 
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Old Jan 26, 2015 | 01:42 PM
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Default Eccentric Bolts vs Camber Plates

Hi Tadge -

Has your team considered replacing the Corvette LCA eccentric bolts with camber plates, and handling camber and caster with shims on the UCA? It might make alignments take a bit longer the first time, but they'd hold more solidly for those of us that like to track our cars.

Thanks!
Old Jan 31, 2015 | 08:58 PM
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Originally Posted by jvp
Hi Tadge -

Has your team considered replacing the Corvette LCA eccentric bolts with camber plates, and handling camber and caster with shims on the UCA? It might make alignments take a bit longer the first time, but they'd hold more solidly for those of us that like to track our cars.

Thanks!
Good question
Old Feb 4, 2015 | 05:23 PM
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+1 Great question
Old Apr 1, 2015 | 12:11 AM
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Originally Posted by jvp
Hi Tadge -

Has your team considered replacing the Corvette LCA eccentric bolts with camber plates, and handling camber and caster with shims on the UCA? It might make alignments take a bit longer the first time, but they'd hold more solidly for those of us that like to track our cars.

Thanks!
+100 After a track alignment I tracked the car for two days under moderate conditions and the alignment is well off after checking today (and another $135 later)... there's gotta be a better way for a $100K car!!!
Old Apr 5, 2015 | 08:22 AM
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Good question.

One should also ask in the same question why one has to take washers out behind upper rear A-arm to get track camber with appropriate rear toe, and why rear toe adjuster has insufficient adjustment range to get track alignment in terms of rear camber if one does not take washers out. Could they not have just designed the suspension so you could simply take it to an alignment shop and go back and forth between track and street alignment. Also virtually no alignment shops will check rear caster. Why not have made the suspension adjustments such that rear caster stays fixed when changing camber and toe, such as by lengthening or shortening the position of the upper ball joint for camber.
Old Apr 7, 2015 | 05:42 AM
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Excellent Question after what happened at the Motor Trend Willow Springs test.
Old Apr 12, 2015 | 06:57 PM
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We need to get out the vote to get this question in the lead quick.
Old Apr 17, 2015 | 05:50 PM
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Potentially, not enough owners can wrap their heads around this topic. Got my vote, but I'm not getting my hopes up absent a Renaissance movement in the forum.
Old Apr 17, 2015 | 06:50 PM
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Originally Posted by SBC_and_a_stick
Potentially, not enough owners can wrap their heads around this topic. Got my vote, but I'm not getting my hopes up absent a Renaissance movement in the forum.
I agree with your analysis: not enough C7 owners understand (or perhaps care) about the difference. It's just the track rats, which I'm one of. I may bring this back up when we have less-interesting topics afoot, and perhaps even take moderator's choice with it at that time.
Old Apr 18, 2015 | 05:42 PM
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Originally Posted by jvp
I agree with your analysis: not enough C7 owners understand (or perhaps care) about the difference. It's just the track rats, which I'm one of. I may bring this back up when we have less-interesting topics afoot, and perhaps even take moderator's choice with it at that time.
agree. Will Wait till next time for one of my get out the vote threads. Dont want everyone to think I get my way all the time.
Old May 4, 2015 | 03:16 PM
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To the top. I'd like to see more technical insight for this car.
Old May 5, 2015 | 08:42 AM
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I have to question the feasibility of this. In terms of getting alignment on the car, it'd require an inventory of plates with position holes. That means every dealer would have this on hand and available to align one of these cars, not to mention an alignment would likely become a dealer only process.

My vettes are always reduced in ride height, so I've very selective where I go. Over the years I've simply bought smart strings, the camber gauge, and all the equipment necessary to align my car myself and really never looked back. People at the alignment shops always argued with what the computer said it should be, versus what I wanted, etc.

I just think if an alignment is becomes that critical, then the investment in the plates and even bushings is warranted. There is a lot bushing deflection alone, which creates a lot of dynamic changes. In another sense, maybe a redesign of the eccentrics that allow them to lock in place would be appropriate.
Old May 5, 2015 | 08:54 AM
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Originally Posted by RC000E
I have to question the feasibility of this. In terms of getting alignment on the car, it'd require an inventory of plates with position holes.
No it wouldn't. There could theoretically be a single plate with the LCAs pushed as far outward as possible. The chassis bolts for the UCAs would need to be a bit longer, and stacked with washers or shims. More shims == less negative camber. And then once set, it can't move.
Old May 6, 2015 | 08:05 PM
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Ohhh...yeah, I gotcha now. Yeah...I believe the 350z guys have a lockout kit somewhat similar iirc. The GT3 Porsche also has a shimmed LCA if I recall that correctly as well...I'd have to google.

Good thing to consider though for sure. Improves alignment consistency with no real downside such as harder bushings or heim's, etc.
Old May 7, 2015 | 05:41 AM
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Originally Posted by jvp
No it wouldn't. There could theoretically be a single plate with the LCAs pushed as far outward as possible. The chassis bolts for the UCAs would need to be a bit longer, and stacked with washers or shims. More shims == less negative camber. And then once set, it can't move.
Wouldn't that be nice!

One item that might be an issue is that shims on top arm would require caster be adjusted at the upper A-arm mounting points rather than at the lower A-arm mounting points via the eccentrics. It is possible that the suspension designers for the C7 would say that caster is better adjusted from the bottom than from the top in terms of optimal geometry (camber and toe change versus suspension travel, etc).

We could have a nice little velour bag with a Stingray logo on it to carry our spare shims. Alignment guys would say "Huh" when you gave them the bag.

And of all the vendors I have contacted (LG, Pfafdt, and a couple of others), no one is making an alignment kit for the C7.
Old May 27, 2015 | 11:00 PM
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+1 voted; good question.
Old May 30, 2015 | 04:52 PM
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I had my friend's Z06 up on my lift today to change out his diff fluid which was full of metal just like mine after only 1 track day and a few thousand miles, and his rear lower A-arm bolts are mounted the same way as on my Z51. Both bolt heads on the lower A-arm point toward the front of the car. The front lower A-arm bolt cannot be removed except by lowering or removing the entire rear sub-frame. We checked in my Helms manual for the procedure to remove the lower rear A-arm, and it confirms you must drop the subframe to remove the lower front bolt out of the A-arm. The reason is the front bolt would be blocked by the gas tank and cannot be pulled out of the bushing.

So what this means is that you cannot use camber plates with pre-set hole locations in them to set alignment in a C7, unless you first drop or at least lower the entire rear subframe to get the OEM bolts out and put the aftermarket bolts in backwards. The Helms manual specifically says to re-install the bolts with the heads toward the front of the car. Not sure why, perhaps just to make the alignment rack guy's job easier with both nuts for the lower A-arm adjustments toward the rear. I would be interested to hear if anyone has a different idea as to why the manual would say to install the bolts with the head toward the front of the car other than the one I mentioned.

I checked with 3 companies that make camber plates and bolts for the C5/C6, and not one of them is making them for the C7. My findings above might be why.
Old May 31, 2015 | 08:38 PM
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Originally Posted by descartesfool
I had my friend's Z06 up on my lift today to change out his diff fluid which was full of metal just like mine after only 1 track day and a few thousand miles, and his rear lower A-arm bolts are mounted the same way as on my Z51. Both bolt heads on the lower A-arm point toward the front of the car. The front lower A-arm bolt cannot be removed except by lowering or removing the entire rear sub-frame. We checked in my Helms manual for the procedure to remove the lower rear A-arm, and it confirms you must drop the subframe to remove the lower front bolt out of the A-arm. The reason is the front bolt would be blocked by the gas tank and cannot be pulled out of the bushing.

So what this means is that you cannot use camber plates with pre-set hole locations in them to set alignment in a C7, unless you first drop or at least lower the entire rear subframe to get the OEM bolts out and put the aftermarket bolts in backwards. The Helms manual specifically says to re-install the bolts with the heads toward the front of the car. Not sure why, perhaps just to make the alignment rack guy's job easier with both nuts for the lower A-arm adjustments toward the rear. I would be interested to hear if anyone has a different idea as to why the manual would say to install the bolts with the head toward the front of the car other than the one I mentioned.

I checked with 3 companies that make camber plates and bolts for the C5/C6, and not one of them is making them for the C7. My findings above might be why.
interesting I did not even notice till now. good find.
Old Mar 3, 2016 | 11:12 AM
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any progress on this front?

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