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Statistical Analysis of Cam Failure

new 10/2/02

I did some statistical analysis of the cam failure data on the website. (I say statistical analysis but I never studied statistics, so it is probably pretty crude.) Anyway, I thought I would get your impression of the results. Also, you can use these any way you want, whether you want to post them on the site on just cut and paste into a message to put on the discussion list, or not. I did it for my own interest.

Here are my results, as of 9-30-02:

I found a total of 93 separate failures documented.

Of these, 78 indicated the year model of their cars.
35- 1996's
29- 1997's
5- 1998's
9- 1999's
I wonder if this indicates an improvement in the manufacturing methods for the engines produced later, or does it indicate fewer SHO's sold in later years or fewer miles driven by newer cars?

Of the 93 failures, 71 indicated the mileage at failure. The mileage’s break down as follows:
0k-30k miles 2 failures
31k-40k 2
41k-50k 12
51k-60k 11
61k-70k 9
71k-80k 5
81k-90k 16
91k-100k 6
101k-110k 2
above 110k 6
This indicates that there isn't a "safe zone", they can fail at just about any time.

Bob James Jr.

Thanks Bob,

My count is ~ 125 as of 10/1/02 but folks who ask me to remove or not post their story get my cooperation. 

In round even numbers production by year is:

1996 - 25%
1997 - 50%
1998 - 12%
1999 - 12%

So we might expect (wear being the same, and it is not) 75% to be 96-97 model year. Your numbers indicate 82% which I think is because 96-97 SHOs simply have more miles.  

Using your numbers I get an expected life ~72.5k miles which is close to what I guessed ~ 70k. 

Most folks average 10k-12k miles per year so I expected this summer to be a bad year for 97's, this was the year most 97 hit 70k. I assume last summer 96 got the worst of it and next year 98's will hit the cam wall.  

It would also be nice to chart by month, but we have as many CA & FL SHOs lose a cam, those cars never saw a hard frost so it does not seem weather related.


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