GN questions

[Rollinsperf]

Dear Jack,
Another shop has asked for suggestions on a GN they installed a Harper Racing motor in. 1/4 mile times are 11.10 @ 130 but the 60' is 1.87. Horsepower is 610 at the rear wheels with 55' injectors and alcohol injection.
He's supposed to get back to me on turbo size but I believe it's a Garrett T60, but with the 2200 converter it's only getting 5' of boost off the line and 24' total. I wanted to talk to an expert before I made suggestions.