A question on the Ozrodders site made me wonder a little. With all the NCOP engine limits, I had heard a legend that you could “engineer a car as a commercial vehicle with no engine constraints”. I had always thought it was a myth (or that someone was stretching the rules beyond their intent), but decided I would see if I could understand how it works. Forgive this long-winded post as I try to put down on paper the logic. It duplicates some info earlier in this thread, with apologies.
CAVEAT: At any stage of the argument below, an engineer can say “Naah, all good, you can have a much larger engine”. The story below is not about “my engineer will approve anything”… its more about “this is what the rules give as guidance to the engineer”.
National Code of Practice for Light Vehicle Construction and Modification (NCOP) Section LA Engine Section 2.13 Engine Capacity Table LA Recommended Maximum Engine Capacity sets engine constraints for vehicles. NCOP Section 2.13 Vehicle Mass says that the mass of the vehicle referred to in Tables LA1, LA2 and LA3 is the original (unmodified) tare mass of the model vehicle fitted with the largest engine available for the model in Australia but without optional accessories (air conditioning, tow bars etc.). The mass of the vehicle, whether it is a sedan, station wagon, utility, etc., should be based on the heaviest sedan version of the model sold in Australia. We saw in the post above that a defendable set of calculations gives:
- NCOP Table LA outcomes.png (22.27 KiB) Viewed 1231 times
So where does the “commercial” bit come in?
NCOP Section 2.13 states that:
“Table LA1 does not apply to commercial (ADR Category NA and NB1) or four wheel drive off-road (ADR category MC) type vehicles such as commercial vans, light trucks, small buses, etc. for which there are no set recommended limits.”
Whilst FB/EKs were not 4WD vehicles, this sounds promising, as the early Holden utilities and panelvans were referred to as Holden as “commercial vehicles” in all their documentation (e.g. the workshop manuals described above). Unlike the other body shapes, utilities and panelvans also had maximum load plates riveted to the inner guard. Maybe this is enough to convince an engineer (“NCOP says commercials have no limits, and Holden called them commercials”). But maybe the engineer gets pedantic about “ADR Category NA and NB1”. So let’s dive a bit deeper into those Categories.
Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005 defines the ADR Categories. This Standard uses Gross Vehicle Mass (GVM). From the posts above we already have tare weight and kerb weight, now we just have to work out the GVM. We need to be a little careful here with the weights we use. When we were assessing within NCOP, we had to use the “the heaviest sedan version of the model” rule, even though we were applying to any of sedans, utes, wagons or vans. Now that we are checking a definition inside the Vehicle Standard, the “heaviest sedan version of the model” rule does not apply, and we need to use the individual weights for utes and vans.
GVM is defined as “the maximum laden mass of a motor vehicle as specified by the ‘Manufacturer’.”. It is equal to the kerb weight, plus the driver and passengers, plus the load (effectively everything that the car is designed to “push down on the road with”). For the early Holden commercials, the GVM was referred to as gross weight, and noted on a tag in the engine bay. The tags look like this:
- Maximum gross weight plate.png (370.12 KiB) Viewed 1231 times
The information is also contained in the Commercial sales brochures released by GMH. The front cover and specifications page for FB commercials looks like this:
- FB Holden commercial sales brochure first page.png (1.4 MiB) Viewed 1231 times
- FB Holden commercial sales brochure specifications page.png (1.37 MiB) Viewed 1231 times
… and the front cover and specifications page for the EK commercials looks like this
- EK Holden commercial sales brochure first page.png (2.05 MiB) Viewed 1231 times
- EK Holden commercial sales brochure specifications page.png (1.38 MiB) Viewed 1231 times
From our early Holden engine bay tags and the commercial sales brochures:
FB Holden van GVM (gross weight): 1524.1kg (30cwts)
FB Holden ute GVM (gross weight): 1524.1kg (30cwts)
EK Holden van GVM (gross weight): 1651.1kg (32.5cwts)
EK Holden ute GVM (gross weight): 1625.7kg (32cwts)
We are also going to need the “unladen mass”. The Vehicle Standard defines this as “the mass of the vehicle in running order unoccupied and unladen with all fluid reservoirs filled to nominal capacity including fuel, and with all standard equipment.”. This is equivalent to the “kerb weight” given in the workshop manuals, though again we will need this number for both utes and vans, not just “the heaviest sedan version of the model”.
From the factory workshop manuals for our early Holdens:
FB Holden van unladen mass (kerb weight): 1160.7kg (2559lb)
FB Holden ute unladen mass (kerb weight): 1120.4kg (2470lb)
EK Holden van unladen mass (kerb weight): 1139.0kg (2511lb)
EK Holden ute unladen mass (kerb weight): 1112.2kg (2452lb)
Now that we have our GVM and unladen mass, what does the Vehicle Standard say that an ADR Category NA and NB1 commercial vehicle is? Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005 Section 5.7 says that an NB1 vehicle is 3.5 -4.5 tonnes gross vehicle mass. As we saw above, the GVM is not that heavy for our early Holden, so we cannot be an NB1 commercial vehicle. We will need to comply instead with Category NA.
Section 4.5.5. Light Goods Vehicle (NA) indicates an NA commercial vehicle is “A goods vehicle with a ‘Gross Vehicle Mass‘ not exceeding 3.5 tonnes.” We can meet the “GVM less than 3.5 tonnes” part easily from our GVM information above. Now we need to demonstrate our early Holden is a “goods vehicle”. Section 4.5 Good Vehicles says we need to be “A motor vehicle constructed primarily for the carriage of goods and having at least 4 wheels; or 3 wheels and a ‘Gross Vehicle Mass‘ exceeding 1.0 tonne”. FB/EKs have four wheels, (and a GVM greater than 1.0 tonne even if it had 3 wheels
). So far so good. The utes and vans are made to carry goods… so this may be enough to convince the engineer (we might again need to fall back here on Holden’s consistent use of the word “commercial” to show that the vehicle was constructed primarily for the carriage of goods).
If the engineer gets really pedantic, they could say that utes and vans were not made “primarily” for the carriage of goods – they were made primarily for the carriage of the general public, and the goods carrying was just a side-hustle. There is guidance under Section 4.5.2 that decides whether the vehicle is “primarily” a goods vehicle, or a side-hustle. Section 4.5.2 allows that “A vehicle constructed for both the carriage of persons and the carriage of goods shall be considered to be primarily for the carriage of goods if the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladen Mass‘. Dammit… now I have to do some maths.
For our FB van,
a) The number of seating positions is three (bench seat).
b) The GVM is 1524.1kg.
c) The unladen mass is 1160.7kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladen Mass‘”, i.e.:
(3 x 68) < (0.5 x (1524.1-1160.7), i.e.:
204<181.7
This is not true, hence we cannot demonstrate that an FB van meets the definition of having been made primarily for the carriage of goods. We would need to use an argument that there are only 2 seating positions in an FB van. Then we get:
a) The number of seating positions is two.
b) The GVM is 1524.1kg.
c) The unladen mass is 1160.7kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladean Mass‘”, i.e.:
(2 x 68) < (0.5 x (1524.1-1160.7), i.e.:
136<181.7
This is true, and hence an FB van meets the definition of having been made primarily for the carriage of goods only if we accept that there are only two seating positions. Therefore an FB panelvan with two seating positions is a commercial Category NA vehicle as defined by Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005, and Table LA1 of the National Code of Practice for Light Vehicle Construction and Modification (NCOP) Section LA Engine does not apply (i.e. there are no set recommended limits for FB panelvan engine capacity).)
For our FB ute,
a) The number of seating positions is three (bench seat).
b) The GVM is 1524.1kg.
c) The unladen mass is 1120.4kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladen Mass‘”, i.e.:
(3 x 68) < (0.5 x (1524.1-1120.7), i.e.:
204<201.7
This is not true, hence we cannot demonstrate that an FB ute meets the definition of having been made primarily for the carriage of goods. We would need to use an argument that there are only 2 seating positions in an FB ute. Then we get:
a) The number of seating positions is two.
b) The GVM is 1524.1kg.
c) The unladen mass is 1120.7kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladean Mass‘”, i.e.:
(2 x 68) < (0.5 x (1524.1-1120.7), i.e.:
136<201.7
This is true, and hence an FB ute meets the definition of having been made primarily for the carriage of goods only if we accept that there are only two seating positions. Therefore an FB utility with two seating positions is a commercial Category NA vehicle as defined by Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005, and Table LA1 of the National Code of Practice for Light Vehicle Construction and Modification (NCOP) Section LA Engine does not apply (i.e. there are no set recommended limits for FB utility engine capacity).)
For our EK van,
a) The number of seating positions is three (bench seat).
b) The GVM is 1651.1kg.
c) The unladen mass is 1139.0kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladen Mass‘”, i.e.:
(3 x 68) < (0.5 x (1651.1-1139.0), i.e.:
204<256.1
This is true, and hence an EK van meets the definition of having been made primarily for the carriage of goods. Therefore an EK panelvan is a commercial Category NA vehicle as defined by Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005, and Table LA1 of the National Code of Practice for Light Vehicle Construction and Modification (NCOP) Section LA Engine does not apply (i.e. there are no set recommended limits for EK panelvan engine capacity).
For our EK ute,
a) The number of seating positions is three (bench seat).
b) The GVM is 1625.7kg.
c) The unladen mass is 1120.4kg
We have to show that:
“the number of seating positions times 68 kg is less than 50 percent of the difference between the ‘Gross Vehicle Mass‘ and the ‘Unladen Mass‘”, i.e.:
(3 x 68) < (0.5 x (1625.7-1112.2), i.e.:
204<256.8
This is true, and hence an EK ute meets the definition of having been made primarily for the carriage of goods. Therefore an EK utility is a commercial Category NA vehicle as defined by Vehicle Standard (Australian Design Rule – Definitions and Vehicle Categories) 2005, and Table LA1 of the National Code of Practice for Light Vehicle Construction and Modification (NCOP) Section LA Engine does not apply (i.e. there are no set recommended limits for EK utility engine capacity).
In summary:
NCOP provides engine guidance for modifying FB/EK Holdens. There is significant flexibility in what an engineer can approve. A defendable, NCOP compliant position for engine capacity is shown in the table below:
- NCOP Table LA and commercial outcomes.png (30.57 KiB) Viewed 1231 times
Cheers,
Harv
327 Chev EK wagon, original EK ute for Number 1 Daughter, an FB sedan meth monster project and a BB/MD grey motored FED.
). So far so good. The utes and vans are made to carry goods… so this may be enough to convince the engineer (we might again need to fall back here on Holden’s consistent use of the word “commercial” to show that the vehicle was constructed primarily for the carriage of goods). 
i've asked numerous and they've all said it's a myth everything is based off a base model unmodified sedan, in NSW