Modified Cars

Cars that have been modified (major modifications) require an engineer report (VASS certificate) to be lodged with VicRoads in order to be legal on the road and covered by your insurance.
Bonneville Consulting can provide you with the engineer report (VASS certificate) in order to obtain full registration or club permit registration.  
Modifications on a vehicle are quite common and can vary from changing wheels to engine conversion. Not all modifications require an engineer report, minor modifications are exempt. Refer to VicRoads VSI 8 bulletin for the classification of modifications.

Common major modifications that are carried out and have been certified by Bonneville Consulting:

  • Performance engine change (power increase by more than 20%): V8 conversion
  • Brake modifications: discs upgrade
  • Body modifications: convertible, fibreglass body fitment, utility conversion (i.e. Nissan Patrol ute conversion)
  • Additonal seats & seat belts

All modifications are required to comply with VSB 14. For instance, a performance engine change will require an assessment in accordance with section LA of VSB 14, it will involve an inspection, a brake test, a noise test and an emission test to be performed. Additional safety upgrades (inertia reel lap/sash seatbelts, collapsible steering column) are also required as part of the conversion.

Please fill the vehicle details form and email it to This email address is being protected from spambots. You need JavaScript enabled to view it.. We will respond and provide you with a quote also. Depending on the modifications and date of manufacture of the car, different ADRs and requirements apply. It is advisable to find out which modifications are not allowed before your start your project.

Common modifications that are carried out and have been certified by Bonneville Consulting: 

  • Performance engine change: V8 conversion
  • 4x4 Utility cabin conversion 
  • Additional seats in van
  • Imported cars and imported bikes

Modifications that Bonneville Consulting does NOT inspect and certify: 

  • Modified suspensions (front or rear)
  • Modified steering and RHD conversion
  • Roll cage installation
  • Structural modification
  • Turbo / Supercharged engine
  • 4x4 suspension lifts (>50mm) and larger wheels (35''')


1966 Ford f100 WITH 460 v8

1966 Ford F100 with 460 V8

 66 F100 with 460 v8

Big Block 460 in F100

 57 Ford customline with EB V8 5l engine

1957 Ford Customline with EFI 5L V8


Nissan patrol ute conversion


1989 Maxda Rx7 with larger intercooler

Mazda RX7 with larger intercooler