just curious the amount of passes your's last ?
Can you share details of your application and what springs are you running?It's going to depend on lift, seat and open pressure, and length of RPM. If you're only that high for 2-3 seconds compared to 9,000+ for the second half of the track.
My little engine sees almost that in the water, and over that on the track. I've got over 150 1/4 mile passes on the springs, and they still have great seat pressure. I do check them every 2-3 race days just to make sure I don't run into any problems