71 replies to this topic

[Martinracing98]

If someone would just discuss parity, this topic would be complete

[38bfast]

figures. when SCCA made them legal we asked if anyone had seen any failures and all we got back was crickets. 

[Bench Racer]

Ralph, back in the day when the SMAC was doing track widths, did anyone ever do the ground powder tire patch measurement reference to top of wheel openings with non bastardized fender/bodywork?  

[Jamz14]

We broke one at the last 6-hour enduro for WERC @ Utah Motorsports Campus.  Of course with ~15 minutes to go in the race.  Luckily we had a 15 minute and 2 second lead and still won.  Car never had contact, but has had offs and pounded who knows how many curbs over the 3 years they were on the car.  We run the enduro every year, plus a full season (~14 races/year).

So now I have heard of one. 3 years of running and enduros. Probably same failure rate as a control arm or tie rod. I think I can live with that.

[Todd Green]

So now I have heard of one. 3 years of running and enduros. Probably same failure rate as a control arm or tie rod. I think I can live with that.

 

We had our final race this weekend, so I asked around the paddock.  2 other cases of a broken ball joints, but I believe one car had had contact somewhere along the line, so I'd dismiss one of them.  And yes I'd agree it is rare, just trying to provide anecdotal evidence..  I've had mine on the car since they were first made legal.   Though the vertical bolt on the side that gets the most curb action has come loose twice.   I plan on replacing them this winter.

[Steve Scheifler]

And let’s not discount that the stock ones aren’t exactly indestructible.

[Tom Hampton]

And let’s not discount that the stock ones aren’t exactly indestructible.

They sure don't like slamming into K-wall...I can attest to that much.

[RWP80000]

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

The answer to your question is YES! Members of the SMAC have made several evaluations based on the methods described in the GCR which performs the track width measurement WITHOUT the driver in the car (which is to the advantage of the competitor) and basically is an average of the centerline of the tire through the centerline of the spindle front vs rear with the option of measuring the average from the inside of one wheel to the outside of the other wheel through the centerline of the spindle, averaging the front and rear values.

 

One member of the SMAC developed a special tool designed to pick up these centerline wheel points and then sent the tool to me. Without knowing his results and using the tool on a totally different vehicle, there was excellent correlation to the results between measurements take at the two locations.

I can say that anyone running the 24mm offset wheels better not be running any wheel spacers on the front and that those running the 30 mm offset wheels can feel comfortable running 6 mm spacers when running the offset ball joints.  As to pulling the top in versus pushing the top out, you can use spacers to maximize your track width with the upper control arm offset bushings but you are responsible to make sure your combination would pass when measured by the method listed in the GCR.

 

My preferred method, requiring possession only of a String Alignment tool, is to calibrate and equalize the width dimension of the string pole groove widths, then measuring the average distance from the strings to the wheel lip front and rear, you subtract the side to side string to wheel average distance of front of wheel & rear of wheel dimension from the established String pole groove width.  With this and knowing the overall width of the wheel allows you to determine the wheel centerline dimension by subtracting the width of one wheel from the difference in the average front/rear distance of the string dimension to the outside.

 

Rich Powers

SMAC member

[Ben-AdvancedAutosports]

We replace the OEM ball joints once a year because of the curbs at Road America.  It's not worth the risk of a ball joint failure on track.  Bauer did inform us about 2 years ago that there was a bad production run and warrantied a handful of extended ball joints we were running on a V6 Miata.  We run the offset bushings and haven't had any issues.  It's worth keeping track of failure rates to determine if this is actually a quality issue, or once again just because the Hoosier tires are to big and too sticky.  Are there less ball joint failure issues with the guys running Toyo's in NASA?

[ECOBRAP]

We replace the OEM ball joints once a year because of the curbs at Road America.  It's not worth the risk of a ball joint failure on track.  Bauer did inform us about 2 years ago that there was a bad production run and warrantied a handful of extended ball joints we were running on a V6 Miata.  We run the offset bushings and haven't had any issues.  It's worth keeping track of failure rates to determine if this is actually a quality issue, or once again just because the Hoosier tires are to big and too sticky.  Are there less ball joint failure issues with the guys running Toyo's in NASA?

 

Have not seen any ball joint failures in NASA Norcal region running Toyos.

[Jeronimo Esteve]

Does anyone have the extended ball joints in stock?

[LarryKing]

Did you call Mazda Motorsports?