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Discussion Starter #1
I just recently installed BC Racing coiolvers on my 300 and went to get an alignment done. The tech at Firestone noticed that on the rear left side the metal part against which the camber screw turns is all bent so the camber screw can't turn properly. Apparently the only reason the camber was OK before is because the screw was actually sitting on TOP of the metal part... which is crazy. So right now I have some negative camber in the rear left wheel that needs to be fixed. They quoted me about $150 to try and fix this problem or the tech said that I can purchase a camber & toe kit and replace the arms so that i don't even need that camber screw at all. So i figured might as well take advantage of the opportunity and upgrade some parts. I was looking at the Megan parts and was wondering if these will fix my problem:

Megan Racing

and / or

Megan Racing

Any other suggestions would be appreciated. :confused:
 

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Boosted Troll
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Mega Arms with Moto ends from Figs will suit you well.
HIGHLY recomend Fgis products
 

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Definitely go with Figs Mega Arms and toe links. You can save some money by painting them with truck bed liner.
 

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Discussion Starter #9
Thank you all for the feedback. I'm considering Figs EE Mega Arms or the Race Mega Arms, I see the main benefits of going with the Race Mega Arms is that they weigh lighter and make the suspension stiffer... is there any other benefits to go with Race Mega ?
 

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E2 MEGA Standard Specs

* MIG welded- interlocking tab construction. Ground flat.
* Low cost entry model
* FIGS FXM MOTO rod end standard
* Integral end fitting weldment, tube in box construction.
* Approx 5.3 lbs
* Cost effective solution for tire wear
* New design will work with all aftermarket coilovers
* Slotted shock mount for leverage adjustment.
* 3-position sway bar endlink mounting options.
* Stock Eccetric bolt for fine on-vehicle camber adjustments.(new eccentric bolt included on ISX50, IS-F and Gen3 GS applications)
* Inner rod end adjusts for coarse camber offsets. Requires unmounting for adjustments.

RACE MEGA Standard Specs

* TIG welded- interlocking tab construction.
* Dimpled and lightened for maximum suspension response and stiffness.
* FIGS FXM MOTO rod end standard 3-Piece Aurora AM12T Optional
* Integral end fitting weldment, tube in box construction.
* Upper triangle gusset standard.
* Approx 4.6 lbs
* Cost effective solution for tire wear
* Slotted shock mount for leverage adjustment.
* 3-position sway bar endlink mounting options.
* Stock Eccetric bolt for fine on-vehicle camber adjustments.(new eccentric bolt included on ISX50, IS-F and Gen3 GS applications)
* Inner rod end adjusts for coarse camber offsets. Requires unmounting for adjustments.

O2 MEGA Standard Specs



* TIG welded.
* Precision 3-piece PTFE-lined rod end
* 4140 Alloy Steel rolled-thread inner coupling, 7/8"-16 Male and 3/4"-16 female threads. Zinc-plated. This is the OVAS(On.Vehicle.Adjustment.System) fitting.
* 6061 anodized aluminum pinch clamp, hardened c-clip and grade 8 pinch clamp hardware.
* FIGS "F" insignia machined into end fitting
* Best performance for Track and Competition.*Requires High Spring Rates
* Approx 4.75 lbs
* 3-position sway bar endlink mounting options.
* Stock Eccetric bolt for fine on-vehicle camber adjustments.
* Inner rod end adjusts for coarse camber offsets on-vehicle.
taken from his sight:
..FIGS SUSPENSION IS300 IS350 IS-F IS250 GS300 ::--


it looks like the weight and the type of welding. and of course cost.
 

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BC Racing

This might be a little off topic, but I just got my BC Racing coilovers too. The ride is awesome, but on the larger potholes, I can hear clunking noises. Is this normal? Do you have the same noises?
 

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Discussion Starter #12
This might be a little off topic, but I just got my BC Racing coilovers too. The ride is awesome, but on the larger potholes, I can hear clunking noises. Is this normal? Do you have the same noises?
not sure what you mean by clunking noises but personally i dont have any issues with my coilovers, unless, i go over some major potholes and thats when it feels like i have bricks instead of springs & shocks. your best bet is to avoid every dent in the road.
 

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Also for reference on my arms, I recently divided the product offering again, thus the new names. For history sake, the S3 MEGA was the same as the RACE version but MIG welded and it used a different HEX end fitting for the rod end mount. The new models use a solid machined transition piece which is easier to weld in and is stronger than previous versions. The main motivator being to reduce fabrication time. Similarly, you can think of the EE version is a cost reduced version of the S3 with no dimples.

Regarding the BC coils making noise. Where did you order them from? I sell all mine with rubber upper mounts because the pillow balls will make noise and they serve no purpose ona double wishbone setup. It can also be from imporper spring preload (top perch) being too loose or potentially a bad seal in the damper stack from a large impact previously. So you may need a new cartridge on that shock. Shocks get damaged if you take large impacts frequently and the cylinder pressure becomes higher that the seal pressure. Once its blown that means it probably rolled out of a seal channel and the piston might slap against the side of the body in that case, thus the noise. Or it would be related to another component in the suspension, its hard to say. Noise gremlins are hard to isolate.

A final word, keep in mind that your problems are not entirely camber related, but toe related. The toe link and the lower control arm counter act each other as the suspension compresses and the net result of the stock setup is horrible toe-in under compression. The Mega arms allow a short arc on the control arm to counteract the toe link. The adjustable toe links go one step further and lengthen the toe link arc to reduce how much toe in happens. I find it hard to image that your camber eccentric rest is bent on the control arm, but believe it of its the inner toe link mount as that is the one prone to bending. See here as I had to hit mine with a cold chisel to form them back into shape.


If you want a significant improvement in handling as well as geometry correction, then mine is really the only complete solution as it is the only one to replace the OEM rubber bushing with a spherical. If you just want mild correction, then the SPC ball joint will work to get the specs correct on the rack, but it will not balance the suspension to work better at the new lowered state. I should also mention that stock alignment settings are no good when you go past an inch of lowering. A lowered IS suspension will rewuire more toe out in the rear and more toe in up front due to the bump steer influences. And also make the tech get them balanced side to side. I have seen too many alignment sheets with cross toe at 0 but one side is positive and the other negative.

That is all I got for now.
Fig
 

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I just recently installed BC Racing coiolvers on my 300 and went to get an alignment done. The tech at Firestone noticed that on the rear left side the metal part against which the camber screw turns is all bent so the camber screw can't turn properly. Apparently the only reason the camber was OK before is because the screw was actually sitting on TOP of the metal part... which is crazy. So right now I have some negative camber in the rear left wheel that needs to be fixed. They quoted me about $150 to try and fix this problem or the tech said that I can purchase a camber & toe kit and replace the arms so that i don't even need that camber screw at all. So i figured might as well take advantage of the opportunity and upgrade some parts. I was looking at the Megan parts and was wondering if these will fix my problem:

Megan Racing

and / or

Megan Racing

Any other suggestions would be appreciated. :confused:
I am going to be 100% honest here. We do not condone the use of Megan products, however far before FIGS or anyone else out there had anything worth a damn, we used Megan on our car for a long time with no problems. So I would feel comfortable recommending this setup to you.
 

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A lowered IS suspension will require more toe out in the rear and more toe in up front due to the bump steer influences. And also make the tech get them balanced side to side. I have seen too many alignment sheets with cross toe at 0 but one side is positive and the other negative.
Since we're on the subject, I'm always at a loss of what to ask for when I bring my car to the alignment shop. In degrees, what would an ideal setting/range be for front and rear toe? Also, Does adding more toe in up front help with bump steer at the expense of tread life, or does it help with both issues? Right now, I'm more in need of tread life than all out performance. Thanks.
 

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Discussion Starter #16
Since we're on the subject, I'm always at a loss of what to ask for when I bring my car to the alignment shop. In degrees, what would an ideal setting/range be for front and rear toe? Also, Does adding more toe in up front help with bump steer at the expense of tread life, or does it help with both issues? Right now, I'm more in need of tread life than all out performance. Thanks.
I was kind of wondering the same thing. The most information I was able to find was in this post here. When I told the alignment tech to try -2.12 degree camber like it said in that post he told me that my camber would be too negative, even if in fact the factory specs don't apply at this point. So I'm wondering if the equipment that they use is able to measure proper alignment? He did say that they deal with a lot of lowered cars so I'm wondering how they put them all in spec.
 

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^The image wasn't saying to shoot for -2.12 degrees, it was saying that a 2" drop will change your camber by -2.12 degrees.

I've read some recommendations for 0 toe to maximize tread wear, and I'm pretty sure that others have said 0 toe will chew up tires faster because the suspension tends to compress while driving. Even though the suspension will never be static while driving, compensating for the compressed suspension at speed will be better for tread life than leaving toe at zero...especially if the setting is made with nobody in the car.

Does anybody who is knowledgeable with alignments on lowered cars care to enlighten me on the subject? Thanks.
 

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OK sorry I must have missed the post Rey.

Bump steer is the amount of toe (steering) under compression and rebound. Reducing bump steer prolongs tread life.
When the car is lowered, the linkage starts to incline, meaning it is now moving inward as it also travels upward. The reason why stock settings do not apply is that the neutral settings assume the toe linkage is flat. Since its at an angle, and it will spend most of its time at an angle, the toe settings need to compensate and thus toe out (rear) because it will more drastically toe inward under compression.

So to think of it simply, you need to redefine "center" for which you will go out and in as it travels.

The flip side ( quite literally) is the rebound stroke, where it will now go more toe out. The "zero" setting will also depend on the LCA length and the toe link.

This is why you should buy my arms more than anything else. Its not a static setting, its a balance DURING cycle. You can make the LCA shorter and it will also incline and pull inward, balancing the toe links influence as I said. The toe link likewise can get longer so its arc is longer and it travels less drastically inward under compression. Without adjustment, you are stuck with the stock adjustements, which in the case of the toe link ONLY CHANGE MOUNT LOCATIONS, NOT LENGTH. So not matter what you are stuck with a stock toe link arc length. All this means is that you need to pull more camber (LCA arm length) as you go lower. This intrinsically means pulling toe out, because that is what the LCA does.

Its not a camber issue, its a toe issue, but the camber at a particular drop indicates how much toe is present also and the limit of the factory arm to balance the toe link is the problem.

Take for instance the case where you want to run more negative camber. Extend the LCA and extend the toe link by the same amount or more until you get a favorable bump map. You can drastically change the handling manner of your car with 0.1 degree of toe in the rear.
 

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I am trying to keep up, but what i am getting is you need new LCA's if your going to lower your car and want to improve handling and extend tire life.
 

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Thanks for the info Mike. I think I'm pretty much starting to get it, but not completely. So under compression (while driving), the rear tends to toe in, and I'm guessing that the front tends to toe out. To offset this effect, a lowered car needs a little toe out in back and toe in up front. By doing this, toe will be closer to zero as the suspension compresses and rebounds. Does that sound about right?

The behavior of the front is what isn't making sense to me. Does the front toe move in the opposite direction as the rear under compression/rebound? I can see how adding toe in would make your car feel more stable. However, if front toe reacts the same as the rear (toe in under compression), wouldn't more toe in kill tread life? The toe in will keep your steering straight, but I would expect the front tires to scrub more.

You mentioned that just a 0.1 degree change in toe can significantly affect the way a car behaves. With respect to tread life, how much toe is too much? Since I already have both your LCA's and toe links, my rear suspension geometry should be good to go once I get a proper alignment. I'm trying to figure out an acceptable/optimal range for front and rear toe setting with your Mega Arms and toe links. Sorry, this is one of the topics that I have had a hard time understanding. Thanks.
 
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