| I’ll spare everybody the reasons for the delay in this post. I should’ve posted this sooner like I said I would. Anyway.... Disclaimer: This post contains no data or numbers or lap times. I am basing my claims on my impressions from lots of back-road driving, and that’s all, so take it for what it’s worth. Also, at the bottom of the post I’ve got a question for those who have experience in adjusting suspensions in this manner. I purchased SPL’s front lower control arms about a year ago, and I love ‘em. I was trying to solve a problem with my car that I believed resulted from the lowering. In hard cornering the car seemed to transfer a lot of weight to the outside front tire and unload the inside rear. It felt like when the car rolled, it rolled forward as well as sideways, and the combination put a lot of weight on the outside front. After researching, I used SPL’s front lower control arms to raise my front roll center by adjusting the length of the "ball joint" shank. For the arms, go here:
[ http://www.splparts.com ]
Go to suspension --> Front multi-link The effect is to change the angle of the lower control arms. Here is a picture to illustrate: 
The red line represents the approximate angle of the stock control arm. The blue line represents the approximate current angle. Do not be confused by the green line, which is the angle of one section of the arm itself. That is not important. The blue line is the important one, because it is drawn between the inner and outer pivots on the arm. The green line is just the angle of one section of the arm, and is not what you want to adjust by. Why did I do this? I suggest that you do some google work, because I’m not interested in putting it all in this post. Google searches on the following produced some good links: “suspension roll axis”
“suspension roll center” This link had some good illustrations that I recommend:
[ http://www.tonyfoale.com/Articles/carstuff/spring.htm ] Therefore, when I made the adjustment I raised the front roll center, and probably decreased the angle of the roll axis. I don’t think the roll axis needs to be level; I just think my front roll center was too low, and the axis was too steep. Again, this is based on road feel only. This change has significantly changed the feel of the car in hard cornering. Now the car seems to not transfer so much weight to the outside front tire, and I would guess that it would reduce understeer. Other points:
- I have sensed no additional noise or vibration from these arms, even though they have rod ends with no rubber bushings.
- I have also sensed no improvement in feel from the lack of bushings. I previously had Nismo bushings and it felt great. I think the solid ends are not the reason to buy these arms; it’s the adjustability.
- Caveat emptor: some work was required to get the arms installed. A little grinding, etc was needed, but nothing huge. I'd buy them again.
- After a year of street driving, bumps, rough roads, etc, these arms are holding up great. I have had no problems.
- The degree to which a car is lowered will affect how useful these arms might be. Questions for those who’ve spent time adjusting suspensions:
- Though this change makes the car feel a lot better on the back roads, perhaps it would reduce rear bite when accelerating out of a corner? If the car transfers weight to outside front on corner entry, perhaps it will transfer to inside rear on corner exit, which might be good? I dunno, I haven’t spent a lot of time thinking about it, looking for thoughts.
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Adjusting front roll center: SPL front lower control arms - 
