Delta Wing Vortex Generators

[boof777]

Hi,first post and my vehicle is not at all aero efficient due to its intended use so please no suggestions to un-modify the car.

For info, car is a FZJ105 Landcruiser with 4spd auto and 4.5 L6 gasoline engine. Basically, like the old US model LX450 but with the 100series body.
Basic mods;
Suspension lifted
Steel barwork front and side steps
Intercooled+turbo setup
Unichip Q piggyback ECU
Snorkel
Exhaust
315/75R16 tires
Stage 2 auto valvebody

My main goal with the VGs is to get more stability at highway speeds (100kmh/62mph).

Anyway, I made up some delta wing VGs out of 2024 T3 alloy to try out on the rear edges of my car since it's a tall, square backed wagon.

There are 8 positioned along the top at the rear of the roof approx 100mm from the edge. These are 75mm long with a 25mm height and 25mm base.

I have also made 8 smaller ones to position on the sides of the car. Plan is 3 down each C pillar and 1 in front of each rear wheel well. These will also be placed approx 100mm from the edge. Smaller ones are 50mm in length with the same 25mm height and base as the larger ones.

At the moment the roof mounted ones are mounted as 4 each side of the roof centerline. All 8 have their leading edges angled in towards the centerline of the roof with the center 4 at 15deg to the airflow, then 2 at 10deg and the outermost 2 at 5deg.

Initial tests at 130kmh show the car to be a little more stable and wash coming off trucks travelling in the opposite direction don't upset the balance as they pass. Happy so far.

I just want to know if I am placing these VGs correctly and what other suggestions people have for me. Mainly degrees to airflow. Should they all be at around 15deg?

Cost so far has been $5.50 for a can of black spray paint so I thought its worth my time to investigate these VGs further.

Thanks for reading and I look forward to your responses.