14mm Cam Bolts on Outside of Spring Bucket Arm
 

Has anyone tried using a 14mm Cam bolt like the below link, on the outside (knuckle side) of the Spring bucket?
<--Link to example of Cam bolt

I recently had my car aligned and discovered that at my ride height (Probably fit one finger between fender and tire), I had to add 2 degrees of camber (even with SPC inner toe bolts) to get my toe in below ¼”. This is not ideal. I really don’t want to pay $500 - $1000 to convert my coil overs to true type or pay for SPL midlinks, if I can get the job done with a $20 bolt… I have used these bolts previously on Subaru and S-Chassis cars. I have never had one loosen up. Plus, I always mark them with paint pen so, it would be easy to fix, if I did.

yes and no …
you get what you pay for and do it nice or do it twice

I don't think the OEM camber adjusts were intended to make anything but slight adjustments to the OEM suspension. Seeing that you've modified one portion of the suspension it's unrealistic to think the OEM adjusters are going to suffice. If it was me, I'd save up the cash and do it right.

Thanks for the reply. But am I incorrect in understanding that you have not attempted this? Certainly no office intended but I am hoping someone has actually attempted this.

In theory, the aftermarket arms are are doing nothing more than shortening the arm. They are both linear. In theory, adjusting the outboard (knuckle side) is better than adjusting the inboard (Subframe side). The subframe side affects everything outside of it. Including the spring perch. The more you pull it in, the farther the spring comes inboard. Eventually, it would not seat properly at the top. However, adjusting the outboard side would only affect the knuckle.

The only potential pitfall I can think of is the knuckle coming into contact with the spring bucket arm, itself.

Ive done both and when my camber was still out of spec (by a mile and the car handled like a boat) I bought adjustable components.

Purely from a geometry & logical standpoint - if the car is lowered to where you are only getting 1 fingers worth of clearance between the wheel and the fender than the OEM adjusters are far beyond a plausible solution.

Maybe a $20 bolt is your solution and might be a good 'gamble' but conventional wisdom says it's not.

If you decide to try it, please post up your results to for future members.

Thanks again for the quick response.

Sorry, I am not sure what you mean. What do you mean you have done both? You have installed adjustable bolts in inboard/outboard holes on the spring bucket? Or do you mean you replaced your spring bucket and camber arms with aftermarket substitutes.

I already have aftermarket camber arms. So, I have camber adjustment for days. However, as you already know, the 350z has a ton of toe in under compression that gets compounded by lower ride height. So, if I set my camber down to ~0.7 deg negative, I end up with half a degree of toe in. My target is only about 0.15 total toe in.

I (in my younger year - young dumb and full of cnm) ran eibach lowering springs (bc that was the thing) and it sucked. My mechanic did as much as he could to pull the camber into a reason spec. It didn't work, the car handled like sheeeeet and I bought a set of stillen camber and toe arms.

I got a little smarter and went full coil overs a year or so ago and replaced my OEM spring buckets with SPL traction arms.

so (I am not 100% clear...but) it sounds like you have OEM toe arms and don't have anything to put your toe back to within spec?

Well, I cant make too many comments on things done in one's youth. I have owned S and R chassis cars since the 90s. I believe I may have even CUT springs, at one point. The thought of it makes me cringe. I am over 40 now. I have been building and racing Nissan and Toyota ever since. I even lived in Japan for 8 years and worked at several shops there during that time.

Eibach springs, that is what came installed on my Z. They literally fell into no less than 3 pieces each when I removed them to replace with the BC DR coilovers I currently have installed. I used to think that German springs were good. Granted, they could have been on the car since 2006. So, I shouldn't perhaps judge too harshly

Regarding, adjustment on my Z (a recent acquisition and my first Z car of any kind), I only have aftermarket camber arms (Spherical bearing, turnbuckle style). The spring bucket and traction arms are both OEM. As I mentioned previously, I have installed the SPC toe bolts (that require elongating the subframe slots) on the inboard side of the spring buckets.

The guy I just spoke to at Z1 told me that I should buy a aftermarket traction arms to control toe. On an S-Chassis, lengthening the traction arm has the effect of less toe OUT under compression. This is hugely beneficial on a drift car. However, I don't understand the geometry of the Z well enough to guess what happens when I do the same thing on this car. It didnt sound like the guy I had on the phone did either.

Obviously, you wouldn't want to use the traction arms to control your toe. That's what toe arms are for... But would, for example, lengthening the traction rod by 12mm, have the benefit of less bump steer and the added benefit of allowing me to get the car within the specs I am shooting for? No clue.

I searched all over and cant find where anyone has actually measured the rear toe curve of a Z-chassis and the effects changing tension rod length. But, here is an excellent article about S-chassis. Moto IQ S-chassis Tension Rod

Unless you are prepared to go full spherical on the remaining arms and dial it in on an alignment rack, I wouldnt mess with the traction arm.

I too have spoken to the Z1 guys, they love to go to the traction arm and rear bump steer on the chassis, even when discussing the subframe kit and how it sits crooked if you run it in the "raised" position. They do caveat that they deal with a lot of drift people, but for most the solution is to just raise the car and spring it properly according to grip level so you dont get to the point in the travel where you start to deal with bump steer. It is only when you are trying to go full race where you want all the benefits with no compromise eg "lowest cg possible with min ground clearance with full suspension travel and optimal geometry," that this becomes an important discussion.

To answer your question specifically, I have never ran two eccentric bolts on the same arm. But I generally dont like the idea of running one on the outboard side because the loads that bolt sees do no exactly match those on the inboard side. Although that design looks like it should hold.

If your goal is 1/4" "total" toe, so 1/8" per side, and you can get there with 2deg camber, I would just run 2deg camber.

Thanks for the response.

I am currently sitting at 2 deg of camber and 1/4" toe in. I am not worried about driving these settings to the grocery store. However, I am not at all confident driving them at the track. I will keep doing research and see if I can find someone who has measured and published their toe curves. If all else fails, I think I may just have to bite the bullet and put some aftermarket traction arms, measure the toe curve over a few beers some evening.

I will publish my results.

1/4" toe in per side, or total?

Technically, I have about 0.11 deg per side (0.22 deg total). With 245/45r18 tires that works out to a hair less than 1/4" total toe in.

The more I think about it. 2 eccentric bolts on the spring bucket is not the way to go. I think lengthening the traction rod and measuring the effect on bump steer is going to be a much better method to achieving the handling characteristics I desire.

Still not horrible, but its a labor of love so get it right for you. Those numbers will drive just fine on track or off.

Youve seen this thread I assume:
https://my350z.com/forum/autocross-r...-curves-2.html

Interesting topic, any more?