One other thing to consider is that depending upon head and cam combination his effective rpm range could have easily moved up a notch. For example - when my coupe was stock, it had much more torque down low, but seemed to die out pretty quick past 4800 or so. Now, with my TW heads and cam, I lost alot of the low end torque, but my horsepower curve really kicks in over 3000, and all the way to 5800 (as evidenced on my last dyno session graph).
So, it's possible that he could have pulled away at higher rpms.
Just an idea.
E
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1991 5.0 LX Coupe - 38,000 miles
13.17 @ 106.14 mph w/ 2.138 60'
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