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Old 01-14-2013, 07:08 PM   #21
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Well my alignment bolts FINALLY came in so I hope to get started on this project tomorrow.
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Old 01-14-2013, 09:18 PM   #22
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Brainie's point is a good one. Emilio always recommends more negative camber in front than in the rear. Leafy's procedure is sound but you want to end up with less neg camber in back than in front.

Snippet from 949's alignment page:

Quote:
SuperMiata DD Alignment
>=12" front ride height (measured hub center to fender)

>=4.5" front ride height measured at forward most straight section of pinch weld with 205/50/15 or 225/45/15 tires

Front camber: -2 (or as close as you can get to it)
Caster: >4
Front total toe: 0

Rear camber : -1.8
Rear total toe: 0

SuperMiata Race Alignment

<=12.0"

3.75~ 4.25" front ride height measured at forward most straight section of pinch weld with 205/50/15 or 225/45/15 tires

Front camber: -3 (or as close as you can get to it)
Caster: >+4.5 or max available once you reach camber targets
Front total toe: 0

Rear camber : -2.6
Rear total toe: 0
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Old 01-18-2013, 12:56 AM   #23
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What's the reason for less rear camber?
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Old 01-18-2013, 03:29 PM   #24
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Quote:
Originally Posted by wannafbody View Post
What's the reason for less rear camber?
I don't think of it as less rear camber, I think of it as more front camber. Ideally, we would have zero static camber and the suspension geometry would keep the tread exactly flat on the road during cornering. But that doesn't happen, so we need to dial in some negative camber to compensate for the fact that the tire leans a little.

The simple fact is, the front needs more compensation than the back in Miatas. But, more static negative camber up front makes the car a little less stable on bumpy roads, so the typical nancy-boy alignment compromises maximum cornering for stability. But it's your choice; it's not an iCar.
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Old 01-18-2013, 04:27 PM   #25
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Well you wouldnt want the tire perfectly flat to the road even if the suspension could do that due to the tire likely wanting a different amount of camber for maximum grip and based on carcase flex. And example of the first have, from the Milken tire test data I have I know a Hooiser R25A, under the loading it would typically see on the front outside wheel of our formula car, makes the most grip when it is cambered 1.5* towards the inside of the turn. I also know that the comparable goodyear slick in the same situation requires a different amount of camber for maximum grip and that in other loading situations and other locations (such as the inside front, outside rear, inside rear) the optimal camber is different.

But that is quite off topic and tire testing data that goes that in depth is WAY beyond the scope of anything any of us are interested in.
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Old 02-20-2013, 11:32 PM   #26
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I had to get an quick alignment for a track day this weekend and after looking at the printout I was dumbfounded that they considered a good alignment as positive camber and 6-7 degrees of caster. The guy offered to do it the way I wanted so now I will tell him 4.5 caster, as much front camber as possible and matched side-to-side, rear camber .5 degree less than the fronts and matched as well. Zero toe in front and rear.
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Old 02-20-2013, 11:48 PM   #27
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Jake's beard is legit as ****. I recommend all of you show some respect to the man.
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Old 02-22-2013, 02:20 PM   #28
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If you aren't running the Xida suspension setup is the 949 race alignment still recommended for a track car?
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Old 02-24-2013, 11:22 PM   #29
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Yes.
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Old 10-15-2013, 07:13 AM   #30
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Slight thread change, but still related.

On my 01 (that I picked up as a track car based on this forums advice) I have 15x8 PF01's with 205/50 RE11's. The cars suspension is otherwise stock and the alignment I am going to request is:

-1.5 front camber
as much front caster without affecting camber
0 front toe
-1.2 rear camber
0 rear toe

The problem now is that I need to replace the eccentric bolts because, once again, my steering wheel is all crooked. I have the bolts ready to go, but now I need some pointers on the process. I've pieced together advice from searches and please correct me if I am wrong.

1. Remove eccentric bolts one at a time, marking their position, while supporting the control arm with a jack in a ?? position.
2. Torque the eccentric bolt to 150+ ft lbs or as tight as possible
3. Go get an alignment ASAP.

So, if I do this install correctly and go get the alignment, should I again put the car in the air and torque them down myself?
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Old 10-15-2013, 04:32 PM   #31
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Alaignment shop should tq them fine.
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Old 10-16-2013, 06:36 AM   #32
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So I am still left with one question then. Does the car need to be in the air or not to do this?
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Old 10-16-2013, 08:09 AM   #33
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Needs to be in natural compression not drooping.
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Old 10-16-2013, 10:50 AM   #34
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Alingment shop will end up tightening them under full droop when they alaign the car. Just throw the bolts in and take it to the shop.
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Old 10-17-2013, 07:42 AM   #35
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I will try and convince them to just install the new bolts for me. You wouldn't believe how long it took me to convince them to even do a custom alignment for me in the first place! I'm going to take some advice from earlier in the thread and bring a box of donuts, along with those new eccentrics.
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