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> Wheel Alignment, Is this excessive camber?
technicalninja
post Jul 9 2024, 08:44 PM
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QUOTE(Craigers17 @ Jul 8 2024, 11:53 AM) *

This is Excessive negative camber:



I've always thought that would work GREAT in a "Sphere of Death".

Remember motorcycles and girls similar to a Circus act???

Bigger sphere and no regrets if they crash...
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MartyYeoman
post Jul 20 2024, 12:11 PM
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Sorry it took so long to post this.


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914_teener
post Jul 20 2024, 02:22 PM
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QUOTE(MartyYeoman @ Jul 20 2024, 11:11 AM) *

Sorry it took so long to post this.



Back of the napkin trig calcs....just by quessing aprox. -5.7 degrees.

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fiacra
post Jul 20 2024, 02:37 PM
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QUOTE(MartyYeoman @ Jul 20 2024, 11:11 AM) *

Sorry it took so long to post this.



Thanks Marty! Looks pretty much the same as mine. I did speak to the shop and initially got a wall of defensiveness, but he calmed down after a while and offered to recheck it last week. In the meantime I took it to our local expert, Bill Eason, who gave it a pretty thorough checking over and a hard drive and basically advised to drive it for a while and see how the tires wear. He feels the back end feels soft when changing lanes, but he attributes that to the springs rather than the alignment. Otherwise the car handles well. I decided not to go back to the shop (it's a long drive and I don't need to deal with anybody's attitude), but I do feel like I'd like the rear camber to be closer to factory spec rather than what the shop felt was going to give the best handling. I don't push the car nearly as hard as Bill did when he drove it, and I kind of hate that "knock knees" look. I'm wondering if I put the smallest shim (2mm) back in on both sides if that would be a bit better. This is all new stuff to me, so I'm doing a bit more research and trying to figure out if my thinking is too simplistic.
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technicalninja
post Jul 20 2024, 02:54 PM
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Changing the shim will alter the toe setting and this is the one you need to do on the alignment machine.

Adjusting toe is the bitchy thing

You adjust toe LAST.

Change shims till you're happy with the camber and then set toe.

It CAN be done without an alignment bed but the guy doing it would have to be very familiar with the process.

On a normal car you just adjust a tie rod end, it has a lock nut, and each turn is worth XXX movement.

On a 914 you slightly loosen the bolts and then twist the entire trailing arm to make the adjustment.
What's HARD is moving the entire mass JUST 1/16" of an inch.

It's the tiny adjustments that will drive you crazy...

This is why the Tangerine brackets look like the ticket to me.
https://tangerineracing.com/shop/ols/produc...ng-arm-brackets

If those toe adjusters work like I expect they will they will make the toe adjustment MUCH easier...
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windforfun
post Jul 20 2024, 03:18 PM
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QUOTE(914_teener @ Jul 20 2024, 01:22 PM) *

QUOTE(MartyYeoman @ Jul 20 2024, 11:11 AM) *

Sorry it took so long to post this.



Back of the napkin trig calcs....just by quessing aprox. -5.7 degrees.


Copy that.

tan^-1 or arctan(2"/20") = 5.71 degrees.

(IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif) (IMG:style_emoticons/default/beer3.gif)
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fiacra
post Jul 20 2024, 06:31 PM
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QUOTE(technicalninja @ Jul 20 2024, 01:54 PM) *

Changing the shim will alter the toe setting and this is the one you need to do on the alignment machine.

Adjusting toe is the bitchy thing

You adjust toe LAST.

Change shims till you're happy with the camber and then set toe.

It CAN be done without an alignment bed but the guy doing it would have to be very familiar with the process.

On a normal car you just adjust a tie rod end, it has a lock nut, and each turn is worth XXX movement.

On a 914 you slightly loosen the bolts and then twist the entire trailing arm to make the adjustment.
What's HARD is moving the entire mass JUST 1/16" of an inch.

It's the tiny adjustments that will drive you crazy...

This is why the Tangerine brackets look like the ticket to me.
https://tangerineracing.com/shop/ols/produc...ng-arm-brackets

If those toe adjusters work like I expect they will they will make the toe adjustment MUCH easier...


Thanks, that's helpful. I was wondering what else I would affect if I changed camber. Probably best if I just don't mess with it since I'm not going to be able to set toe myself.
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bkrantz
post Jul 20 2024, 08:09 PM
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QUOTE(fiacra @ Jul 20 2024, 02:37 PM) *

QUOTE(MartyYeoman @ Jul 20 2024, 11:11 AM) *

Sorry it took so long to post this.



Thanks Marty! Looks pretty much the same as mine. I did speak to the shop and initially got a wall of defensiveness, but he calmed down after a while and offered to recheck it last week. In the meantime I took it to our local expert, Bill Eason, who gave it a pretty thorough checking over and a hard drive and basically advised to drive it for a while and see how the tires wear. He feels the back end feels soft when changing lanes, but he attributes that to the springs rather than the alignment. Otherwise the car handles well. I decided not to go back to the shop (it's a long drive and I don't need to deal with anybody's attitude), but I do feel like I'd like the rear camber to be closer to factory spec rather than what the shop felt was going to give the best handling. I don't push the car nearly as hard as Bill did when he drove it, and I kind of hate that "knock knees" look. I'm wondering if I put the smallest shim (2mm) back in on both sides if that would be a bit better. This is all new stuff to me, so I'm doing a bit more research and trying to figure out if my thinking is too simplistic.



Probably a good decision. And I will always start with numbers first and then feelings (about most things in life). Almost 6° (if Marty is right) is insane, and 3° is way too much for driving on the street. I would advise aiming for 0.5°, even on both sides, and with proper toe. Whatever shims it takes to do that are the correct shims.
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Superhawk996
post Jul 21 2024, 11:28 AM
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I’m so confused.

So the expert is advising you to run excess camber and see if your tires wear? (IMG:style_emoticons/default/headbang.gif) Will he pay for the new tires when you don’t like the wear pattern? (IMG:style_emoticons/default/av-943.gif)

Here’s the bottom line: you can run more camber than the OEM spec if you wish to improve handling. This is done all the time for autocross and weekend track day cars.

But if you aren’t throwing the car around in the twisties and that doesn’t seem to match your description of your personal driving style, there is NO benefit to running excess camber at the expense of tire wear. It isn’t a question of IF it will increase tire wear, only a matter of how many miles it will take to do so and whether you “age out” your tires before that wear occurs.

The funniest thing is you don’t even like the look of the increased camber which makes it even the more appalling that these experts keep pushing you to keep running that camber. (IMG:style_emoticons/default/huh.gif)
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Superhawk996
post Jul 21 2024, 11:32 AM
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QUOTE(bkrantz @ Jul 20 2024, 10:09 PM) *

Probably a good decision. And I will always start with numbers first and then feelings (about most things in life). Almost 6° (if Marty is right) is insane, and 3° is way too much for driving on the street. I would advise aiming for 0.5°, even on both sides, and with proper toe. Whatever shims it takes to do that are the correct shims.
(IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif)

I don’t think you can even get to -6 degrees of camber without lowering and/or mods to the consoles. Camber need to be measured off the rim. Measuring camber off the tire will be misleading.

Take Chris up on the offer to set you up with his alignment guy.
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technicalninja
post Jul 21 2024, 12:29 PM
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The post stating -5.7 degrees was SATIRE!

914_teener was bull shitting... (IMG:style_emoticons/default/av-943.gif)

Windforfun had to add a math comment that further led astray. (IMG:style_emoticons/default/stirthepot.gif)

MartyYeoman had posted his actual numbers long before the picture at -2.3 and -2.5

Then he posted the pics...

I agree! The ONLY route I'd suggest now (and on post 35) is to bug Chris. (IMG:style_emoticons/default/devil.gif)

Now, I LIKE my camber and will accept slightly lower tire life to be a tiny bit on the "fat" side.

For a 914 that was street based I'd be hunting -.75 to -1.



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bkrantz
post Jul 21 2024, 07:11 PM
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QUOTE(technicalninja @ Jul 21 2024, 12:29 PM) *

The post stating -5.7 degrees was SATIRE!

914_teener was bull shitting... (IMG:style_emoticons/default/av-943.gif)

Windforfun had to add a math comment that further led astray. (IMG:style_emoticons/default/stirthepot.gif)

MartyYeoman had posted his actual numbers long before the picture at -2.3 and -2.5

Then he posted the pics...

I agree! The ONLY route I'd suggest now (and on post 35) is to bug Chris. (IMG:style_emoticons/default/devil.gif)

Now, I LIKE my camber and will accept slightly lower tire life to be a tiny bit on the "fat" side.

For a 914 that was street based I'd be hunting -.75 to -1.


OK, I plead drug-induced stupidity (had knee surgery last week).

Yup, -2° for the street is insane.

And -.75 to -1° might be the sweet spot for people willing to trade tire wear for a little extra cornering fun.
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