Ok, found this:
Maserati 2004 GranSport Coupe: 1680 kg (3696 lbs)
Hockenheim Short 1:16.20
Vairano Handling Course 1:22.72
Zolder 1:46.45
Autozeitung test track 1:43.10
Nordschleife 8:18.00
SportAuto wet handling test 1:29.60
Ring Knutstorp 1:15.40
Gotland Ring (Northern Loop) 1:39.30
Maserati Grantorismo S: 1880 kg (4136 lbs)
Hockenheim Short 1:16.30
Sachsenring 1:40.99 36/124
Vairano Handling Course 1:21.01
Autozeitung test track 1:42.30
Balocco 2:54.70
Camden Airport (pre 10/2010) 1:11.82
Kyalami 2:05.20
Maserati GranTurisimo: 1880 kg (4136 lbs)
Hockenheim Short 1:17.60
Oschersleben 1:51.22
Autozeitung test track 1:43.60
Inta 1:13.81
Balocco 2:59.20
Maserati 3200: 1590 kg (3498 lbs)
Hockenheim Short 1:18.40
Nordschleife 8:37.00
Vairano Handling Course
MIRA Dry Handling Track
Mantorp Park 1:36.30
Maserati 4200 Coupe: 1580 kg (3476 lbs)
Hockenheim Short 1:19.20
Nordschleife 8:30.00I
Vairano Handling Course 1:23.63
Autozeitung test track 1:46.40
Top Gear Track 1:38.00
I must say I am surprised at the 3200 but it was never the best handling car sure an AC could get closer to a GS. I am also dubious about the weight of the 4200 being 100kgs lighter than the GS, that cant be right.
Source:
http://www.fastestlaps.com