71 replies to this topic

[Jim Drago]

Just a note.. I tried a set of these..  Car was run two weekends and the joint is bad on one already

 

[Mark]

I have had a couple of cars come through that had the extended lbj's and had at least one side failing. On both cars the lbj's were about a season old (9-10 race weekends). Both were NASA cars running Toyo RR's if that matters. 

[Ron Alan]

Just a note.. I tried a set of these..  Car was run two weekends and the joint is bad on one already

Is there slop in the pivoting portion? Moves/makes noise like when you check for bearing failure?

[UCFBrett]

My old car was at Mark's shop when he discovered both were sloppy.

 

By that time, I had two seasons on them. The car felt a little off, too, in that it was difficult to transition smoothly from corner-exit slip angle to straight line acceleration. I keep a closer eye on them now. 

[P.McCammon]

I've seen a few quick failures on champ/wrl cars. IMO the offset bushings are the better option

[FTodaro]

I have never tried these.. Just curious, did all these failures involve an impact at some point to that wheel before the failure?

[steveracer]

My guess would be the extra leverage created by the extended portion causing accelerated wear

[Dave D.]

I have installed a few for friends/customer. To me, they just don't "feel " the same quality of the Mazda unit. They are more in line with a generic aftermarket part like a Moog, Mevtec,etc. On the surface, I would have to say they are the best solution to get camber(less labor easier job) than removing A arms and swapping bushings. However after also seeing a few get loose quickly, I know I would never use them on my own car. For bushings, I will try the Whiteline now as I have had many of the ISC turn on the bore(yes, even after installing the screws, rivets,etc..) and they now turn into another maintenance item needing periodic cleaning and lube.

[Jim Drago]

I have installed a few for friends/customer. To me, they just don't "feel " the same quality of the Mazda unit. They are more in line with a generic aftermarket part like a Moog, Mevtec,etc. On the surface, I would have to say they are the best solution to get camber(less labor easier job) than removing A arms and swapping bushings. However after also seeing a few get loose quickly, I know I would never use them on my own car. For bushings, I will try the Whiteline now as I have had many of the ISC turn on the bore(yes, even after installing the screws, rivets,etc..) and they now turn into another maintenance item needing periodic cleaning and lube.

I have been using the whitelines with a steel rivet and no issues.  Tyler Quance is making and selling a nice set of uppers all ready to go with his bushings in them as wel. 

 

On failure, no contact.. joint loosens up and gets sloppy

[Alberto]

When you rivet or use a set screw, do you drill all the way down to the steel tube?  Or is securing/pinning the bushing material with the rivet or screw sufficient for the bushing not to move?

[FTodaro]

When you rivet or use a set screw, do you drill all the way down to the steel tube?  Or is securing/pinning the bushing material with the rivet or screw sufficient for the bushing not to move?

I am not clear on the second question, but what i do with the whiteline is drill through the control arm and the bushing steel sleeve and install a rivet.

[Steve Scheifler]

Hold on. I’ve used both but it’s been a few years since I did a new install. Both use an inner steel sleeve just large enough for the long bolt to pass through, and with both that inner sleeve/tube is then pinched tight between the big washers (outboard) and the subframe (tube) inboard. That sleeve then serves as the bearing on which the bushing rotates as the arm pivots. So for both types you can’t drill & peg into that sleeve. The Whitelines have an outer metal sleeve which is potentially a little better for pinning than the ISC, but I used fairly large set screws and still went well into the bushing. One thing I found with the Whitelines is that the outer sleeve being less inclined to deform means that they expand the big tubes on the control arm so if you press them back out once to realign they go back in loose and are more likely to rotate and even sheer a small set screw. By contrast, the ISCs deform which then leaves the inner hole too tight on the sleeve and they don’t pivot freely, so I use a small homemade hone to clean them up after pressing in place.

As I’ve mentioned before, both can lead to binding and/or loosening of the big bolt as the inner sleeve cuts into the big washer and subframe. Bottom line, both leave a lot to be desired so I’ll deal with the new ball joints.

[Jamz14]

Ask yourself: Would you rather pull in the top of the wheel to achieve your camber, or push out the bottom of the wheel?

Have ran the same set of ebjs on a car for over 2 seasons without issue. We run many races at buttonwillow which is very hard on suspensions, with the car airborne twice per lap and very hard offs.

But even if the joints were only good for a season, go back to the top of this post and ask yourself the question again on how you would prefer to gain your camber if reliability was not a concern. Then ask yourself why you use the brake pads you do when the rotor wear is many times higher than it would be using oem pads?

Even if the ebjs wear faster than normal, so what? Replace them. I haven't heard anyone say that they have broken one in two.

[Jim Drago]

Even if the ebjs wear faster than normal, so what? Replace them. I haven't heard anyone say that they have broken one in two.

 

 

IMO, the "If" is they are not

 We have a track width rule. Once you achieve that number it is the same whether you bring the bottom out or the top in, the angle is the same, so is the location of the center of the wheel.  I don't think it matters, unless I am missing something?  any engineers have an opinion here? 

[gerglmuff2]

has anyone actually measured track width per the GCR with both? and with and without spacers?

[Jamz14]

Jim, you are correct, angle the same. But.... I haven't blown the track width by pushing the bottom out. Did you blow it when you tried it? I assume not because you dont run a car that runs outside the rules. So I ask again, how do you want to achieve it? Push out the bottom and widen your track and keep the top away from the inside wheel arch, or pull in the top and keep your track the same?

[Jamz14]

Now if you space out the wheel and use the bushings, then track is the same and the top isn't any closer to the inside. So we are back to being indifferent as to which one you choose.

So I guess I would be asking why were yours loose in two races but I haven't worn one out yet? You must be driving harder than my driver.

[Brandon]

has anyone actually measured track width per the GCR with both? and with and without spacers?

 

That'll never be answered irrespective of how "clearly" the process is defined in the GCR.

 

My previous stint on the SMAC when the +24 wheels were introduced and marketed as "SM track-width compliant" resulted in at least two/three meeting's worth of discussions on how to address this overall from a rules perspective. From attempting to eliminate the car being the variable (wheel offset + spacers + which upright == max number) to clarifying how the track is measured on a Miata, it was a fruitless endeavour.

[Jamz14]

Not a fruitless endeavor. Smac agreeing might be fruitless but coming up with an easy to measure(or easy to say that it is compliant) is not. What you describe as two meetings with no consensus matches my impressions of how the group works.

[gerglmuff2]

my understanding is that the GCR spec for track width and method of measuring leaves a lot to be desired, which ultimately means that track width enforcement is not really a thing.