If I remember correctly, Mark's car had 728rwhp.. Ran 9.9 @ 142-144mph.. Apples to Oranges..
Also, you seem to be making some assumptions about Norm's LPE car. The "standard" 542ci might be advertised at 725hp. Norm's car isn't standard.. The guys from LPE have engineered, tuned and delivered a serious viper that Norm built to go as fast as possible.. While the car is totally streetable: 6-speed, carpet, full interior (less passenger seat), A/C, stereo, registration, insurance, etc.. Noone claimed it was a standard package and a docile daily driver..
You can only do so much with a n/a "street" viper. To date, only 3 have been in the 9's.
LPE built 2....
Also found that video and looked into the numbers for you:
>> Video of 9.48 pass <<
Bradenton Viper Nationals 2006
9.48 @ 145.96
9.49 @ 148 (back up run)