Just to set things straight I've road tested all 4 Aussie production cars in GT4.
- All cars were bought brand new for the test ie. 0km on the clock
- All cars were only given a car wash before hitting the track
- All driving aids set to 0 and no changes to factory setup (tyres, camber etc...)
- Reloaded game from 2nd memory card after each car to run the cars under identical B-Spec ability
- Tsukuba and Nurburgring - times are first lap out rolling starts ie. no "hot laps"
- Trial Mountain - times are first 3 laps out after rolling start
- B-Spec left set on 3 (medium pace)
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FPV GT 
Tsukuba - 1,12.054
Nurburgring - 8,34.325
Trial Mountain - 1,53.128  1,47.015  1,46.869  average = 1,49.004
Notes:  Probably on the brakes the longest of all cars tested, and plenty of body roll too.  Was able to stretch its legs on Nurb's long final straight.
 FPV F6
FPV F6 
Tsukuba - 1,11.689
Nurburgring - 8,36.910
Trial Mountain - 1,52.139  1,46.379  1,45.917  average = 1,48.145
Notes:  Showed plenty of neutral slide around Nurburgring.  Changed direction very quickly around Tsukuba and Trial Mountain.
 Holden SS
Holden SS 
Tsukuba - 1,12.805
Nurburgring - 8,47.518
Trial Mountain - 1,54.316  1,48.061  1,47.592  average = 1,50.004
Notes:  Looked good under braking but lacked straight line grunt.  Took the best line around corners.
 Holden CV8
Holden CV8 
Tsukuba - 1,12.332
Nurburgring - 8,40.512
Trial Mountain - 1,53.378  1,47.267  1,47.207  average = 1,49.284
Notes:  Looked smooth and in control at all times.  B-Spec liked sliding this one to the outside ripple strips on exits.
 Pontiac GTO
Pontiac GTO US version of the CV8
Tsukuba - 1,11.609
Nurburgring - 8,41.030
Trial Mountain - 1,54.766  1,48.930  1,48.052  average = 1,50.583
Notes:  Had the least amount of body roll.  Better gearing would see this car improve times easily.
 Chevrolet Corvette Z06 (C5)
Chevrolet Corvette Z06 (C5) Same base engine as SS and CV8
Tsukuba - 1,09.093
Nurburgring - 8,10.015
Trial Mountain - 1.48.835  1,43.245  1,42.823  average = 1,44.808
Notes:  Being a purpose built sports car, it is no suprise that this car is fastest.
 Ford Falcon XR8 V8Supercar '00
Ford Falcon XR8 V8Supercar '00 
Tsukuba - 58.955
Nurburgring - 7,13.167
Trial Mountain - 1,33.876  1,28.817  1,28.142  average = 1,30.278
Notes:  Glen Seton set a high speed record in this car in '00 - 301 km/h at the end of Conrod Straight - yet it tops out at 271km/h down the 'ring's long straight!?
