[will69camaro]

Well went to a private rental last Saturday. In hopes for a 9@150+ I decided to make some changes.

1)adjusted rear shocks for some more weight transfer.
2) replaced the wg spring with a little stiffer one. Boost solenoid having a hard time keeping up with duty cycle above 50%. Pulled the spring that made 7psi on gate out and saw it was a “5.6psi” spring. Put a 10psi spring in it and went about my way.

First pass:
Test the wg spring on gate and ensure the fuel system working. Roll it out slow. Get it in 3rd and lay into it. AFR looking good down the track, so I grabbed second. Ran 13.6@133.



Back to the pits and pull logs. Fuel working perfect. Made the expected 13psi on waste gate. All looks good.

Add duty cycle to it (30%) and go for another pass to see what that makes.

Second pass:
Take off easy again. Looking at logs shift out of first at 4500. Out of second at 5500. Then rev 3rd to 6800.

Car feels good and feels fast. Run a 10.5@147. Promising given the soft 1st and 2nd gear.





Go look at the log and see the car made 18psi in 2nd gear and peaked 21psi in 3rd and 4th after the shifts. But boost still falling back to 15-16 range.

I decide 150mph is very attainable. And it’s happening next pass.

Third pass:
I get greedy. Rev a little more but still soft 60ft. I’m running first out this time.

Grab second gear hard at 6800rpm and 20psi boost. Hard shift and a loud bang out back.



Doesn’t look good. Drove to end of track easy. Rear makes aloud pop when I turn off track. Go to pits and make some figure 8s in and out of load to try and test diff. Acting normally.

Fourth “Pass”:
I pull up again. Same tune. Ready to try again and stay in it. Proceed to burnout and hear a loud pop at the start. Can see me look to my friend on the side to see if he waves me off. He doesn’t.



As I’m at the line, some other friends ran up and got the track to stop me. Apparently more noise than just that pop that isn’t noticeable on camera. Day is done. Diff is done.

Car is up on blocks now and will have diff pulled this week. If it warrants it, I’ll take some pics along the way to show the damage.