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FC - rear camber issue

Old 03-12-08, 06:56 PM
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FC - rear camber issue

I'm having trouble getting anything more than about 1.2* of negative camber in the back of my FC (note, I am trying to increase negative camber, ideally to around 2*). I have both the AWR independent camber adjusters as well as the vertical adjustable link that Mazdatrix sells (forget who makes it).

With the vertical link fully extended (so it is at its longest) and the independent links also fully extended (so there is virtually no thread showing above the lock nut) I am still stuck at -1.2* on the passenger side and -0.9* on the drivers side.

Any ideas on what I could do to increase this? Are my adjustments correct?
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Old 03-12-08, 07:54 PM
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You could lower the car more.

May I ask why you want to increase the camber to around 2* in the rear? Just curious.
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Old 03-12-08, 07:57 PM
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Believe me, the car is pretty low...too much so in fact (tires are rubbing under heavy cornering).

Why I want to increase the camber - combination of tire temps after testing and traction issues. FYI this is an all-out racecar application so tire wear is not a concern.
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Old 03-12-08, 08:09 PM
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That's weird. I'm running the stock vertical link and the AWR's as short as they'll go and I still see -1.2 degrees. Run them any longer and the camber goes more negative than I can use. Anything else been done to the suspension geometry back there? Lowering the car will increase negative as mentioned, which is what I'm trying to react back out, but it sounds like that might force you to run stiffer springs/swaybars

So you know, if you're using the adjustable vertical link you might want to check your pinion angle relative to the trans.

Last edited by frijolee; 03-12-08 at 08:15 PM.
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Old 03-12-08, 08:20 PM
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I think I have it...

Camber is defined by both pivots on the rear swingarm. Normally we just play by moving the inboard pivot up and down with the AWR links (or by adjusting the tilt of the entire subframe via the vertical which in turn adjusts the relative position of the inboard pivots).

However, I'm betting the eccentric bolts that adjust your rear toe were installed upside down. That would move the OUTER pivot down and change camber drastically toward the positive.
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Old 03-12-08, 08:28 PM
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You know what, now that I think about it I just remembered that the previous owner made some modification to the trailing arms to prevent camber gain (it was previously an EP car that was basically limited to running on bias slicks which don't need much camber at all).

I'll have to try swapping in some 'stock' trailing arms and see if that has any effect...
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Old 03-12-08, 09:38 PM
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That makes sense, since bias slicks need very little camber, about 0, and when you lower an FC to EP levels you'll have lots of negative camber from the lowering alone.
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Old 03-13-08, 10:51 AM
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Just confirmed with previous owner that this was the problem. Sorry for the wasted thread, but somewhere in the process of me creating it it jogged my memory
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Old 03-13-08, 12:36 PM
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Some use can come out of it yet. Post pics of the modified control arms for those running bias ply slicks.
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Old 03-13-08, 12:38 PM
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Originally Posted by Black91n/a View Post
Some use can come out of it yet. Post pics of the modified control arms for those running bias ply slicks.
Will do once I have them off. I'll take some side-by-side comparison pics!
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Old 03-14-08, 10:05 AM
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I made them and I can make some more... I still have the jig that I used to make the ones on his car.
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Old 03-21-08, 11:47 PM
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Any word on the pictures of these?

I would love to maybe make them my self

I need to reduces my rear camber
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Old 03-22-08, 11:40 AM
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I'm going to replace them on Monday and will take pics then.
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Old 03-22-08, 09:46 PM
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Ok cool sounds good would you be willing to sell them maybe?
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Old 03-23-08, 11:03 AM
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Probably not, I'm sure I'll have a use for them in the future

PM "EprodRx7" - he posted above in this thread and is the original creator of them. I'm sure he will be happy to sell you a set!
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Old 03-26-08, 01:04 PM
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Originally Posted by Blueman86 View Post
Ok cool sounds good would you be willing to sell them maybe?
You could just buy the camber adjusters mentioned before, especially since your LS1FC is a street car.

Running -1 to -1.5 degrees of camber in the rear isn't that bad for tire wear.
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Old 03-26-08, 11:50 PM
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Well my car is mostly a track car so i want As close to 0 camber as posibul

I just bought the camber adjust track bar so ill see how that dose any word on the pictures of the mod Arms? So i could see how to modify mine
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Old 03-27-08, 12:16 AM
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You want 0 camber? What tires are you going to be using, bias slicks?
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Old 03-27-08, 12:37 PM
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Originally Posted by Roen View Post
You want 0 camber? What tires are you going to be using, bias slicks?
Even with bias slicks you'd want -0.5 to -1* of camber. Not sure why anyone would want 0!
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Old 03-27-08, 12:45 PM
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Maybe in this case the "track" is actually the drag strip? That's the only case I could think of where you'd want such low camber values.
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Old 03-28-08, 02:49 PM
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Well i want close to 0 camber im trying difrent setups, Ive been reading alot about Slipangles ill try to find the write up and show you guy Its pretty good and interesting.

Just to try some thing diffrent see how it works out.
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Old 04-15-08, 12:37 PM
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ive probably got at least -2* in the rear just lowered on coilovers. i actually want a little less
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Old 04-15-08, 12:41 PM
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Thanks for all the responses, but I solved this long ago! I swapped back in some OEM trailing arms and now have -3.5* camber in the rear
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Old 04-15-08, 01:12 PM
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Originally Posted by thetech View Post
Thanks for all the responses, but I solved this long ago! I swapped back in some OEM trailing arms and now have -3.5* camber in the rear
Total? Each side? That is quite a lot of camber, are you sure you need that much?
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Old 04-15-08, 01:13 PM
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Originally Posted by Roen View Post
Total? Each side? That is quite a lot of camber, are you sure you need that much?
Yes sir...the pyrometer looked about right @ 30psi cold pressure with about 15-20* hotter temps on the inside of the tire than the rest.
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