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?

You could lower the car more.

May I ask why you want to increase the camber to around 2* in the rear? Just curious.

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.

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.

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.

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...

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.

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 :)

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!

I made them and I can make some more... I still have the jig that I used to make the ones on his car.

Any word on the pictures of these?

I would love to maybe make them my self

I need to reduces my rear camber

I'm going to replace them on Monday and will take pics then.

Ok cool sounds good would you be willing to sell them maybe?

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!

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.

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

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!

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.

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.

ive probably got at least -2* in the rear just lowered on coilovers. i actually want a little less

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?

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.