[OkieSnuffBox]

Originally Posted by VeloxEric

In the rear LCA thread we state the LCA has a life expectancy of the car. The rear LCA can see ~46,000 3.5G bump loads before it reaches its fatigue limit and begins to deform/degrade. It never fully broke, but it was deforming more than the limit we set on the machine which meant it was past it's yield strength.

What is 46,000 3.5G bump loads? That is a car with extremely sticky rubber (lets say 295-325 slicks), with extremely large aero (1000+ lbs of downforce), with extremely hard suspension (12+k spring rate), hitting a racing curb full on, forty-six thousand times. We estimated this to be 5-10 years of use for some of the most dedicated time attack guys.

I could see a clutch being pressed 50,000 - 150,000 times in a year easily. So yes, I do see the clutch fork seeing a high stress load more often than the rear suspension. Could I have designed a unit that would take the load and last 1 million cycles out of aluminum? Yes. However, to me, it just makes sense to make it from a chormoly, ensure it is under the endurance limit, and not think twice about it.

The LCA unit had a goal of being significantly lighter than OEM. This unit weights approximately 7 oz more, it just doesn't seem worth it to me to try aluminum and have them break in 5 years because I guessed incorrectly at how many times a clutch is pressed in a year. Hope that explains it.

I was looking at the FT86SF link for the sale of your product. It mentions nothing of the sort (even though track guys should understand wheels/suspension/etc are wear items).

I wasn't trying to make some veiled dig at your product, it was an honest question regarding duty cycles and work hardening.