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, turbocharger installation
  • Brake modifications: discs upgrade
  • Suspension modifications: redesign, triangulated, graft, air bag
  • Body modifications: convertible, fibreglass body fitment (i.e. beach buggy), utility conversion (i.e. Nissan Patrol ute conversion)
  • Right hand drive steering conversion

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.

Since every project is different, we advise that you contact us with your project for a feasibility assessment. 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.

Examples of engine change:
  • 1955 Chrevrolet with 350 V8 & discs brake upgrade
  • LJ Torana with RB30DET engine
  • 1974 Mazda RX2 with 13B engine
  • 1969 Toyota Corolla with 4AGZE engine
  • VW Kombi with Subaru 2.2L HO4 engine
  • 91 Nissan Pulsar N14 with SR20DET engine
  • Holden FC with 350 V8
  • 1970 Ford Capri with 302 Windsor
  • Nissan Skyline R32 with RB25DET engine
  • Datsun 240Z with RB25DET or 302 V8


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

1967 Valiant VC with brake  suspension upgrade

Valiant VC with brake & suspension upgrade

RB30DET in LJ Torana

RB30DET into LJ Torana

1989 Maxda Rx7 with larger intercooler

Mazda RX7 with larger intercooler