I have to ask, are the tires chattering/skipping off the line. That is a lot of PSI for a hard tail car and your HP combo. I would think you would be between 4.5-5 PSI.
Hoosiers with only 70 runs are either tires that sat too long or someone told you wrong. We have gotten well over 300 runs on Hoosiers but average 250 runs or so before replacing.
I am thinking too much PSI is causing the tire to skip/chirp leaving he line. You are probably on the verge of bouncing the car on the leave. You may be too aggressive in the converter set up for hard tail car which will also cause this as well. A hard tail car is a very difficult combo to hit. I would swingarm it and forget it. Problem solved.