Quick answer: switch to Manual Transmission, turn off traction control and use a high-powered rear-wheel-drive car such as the BMW M6 Forza Edition. The same setup can earn three stars on all five Drift Zones in LEGO Valley.
Earning every available Drift Zone star unlocks the Scandinavian Brick achievement. If you are working through the rest of the expansion, see our complete Forza Horizon 4 LEGO Speed Champions achievement guide.
Our video showing how to attack the Drift Zones in Forza Horizon 4 LEGO Speed Champions and complete every drift challenge.
I spent well over 30 hours in the LEGO Speed Champions expansion without earning three stars on every Drift Zone. Buying faster cars did not solve the problem. The change that made the difference was switching away from Automatic Transmission so I could keep the engine in the right gear throughout each drift.

The BMW M6 Forza Edition at the Hillcrest Drift Zone in Forza Horizon 4.
LEGO Valley has five Drift Zones. I used either the BMW M6 Forza Edition or a lightly tuned Porsche 911 GT2 RS for all of them. Even the muddy Field Lane challenge can be completed without repeatedly changing cars.
Forest Corners is one of my favourite Drift Zones in the whole of Forza Horizon 4. Its long straights and wide corners give you room to maintain a continuous slide. Keep the revs up, use no higher than third gear and carry a shallow drift along the straights before attacking the wider corners.
The video above was filmed at Hillcrest. Approach from the south, carry plenty of speed and concentrate on linking each drift. I scored more than 100,000 points without needing an extreme angle, so prioritize momentum and smooth transitions.

The computer driver in the BMW M6 looks unimpressed with this drift angle - You'll be looking to make the drifts as deep and long as possible to maximize your score.
Approach Stunt Park Pass from the north and build speed into the first long, wide corner. A strong opening drift can score 30,000–40,000 points. Slow down enough for the tight left-hander that follows, then keep the final drifts linked to reach the roughly 95,000 points needed for three stars.
Falcon S-Bends is slower and more methodical. Use the sharp changes of direction to flick the car between the 90-degree bends and keep each slide connected. I first completed this zone in the Porsche 911 GT2 RS, even with Automatic Transmission, so it is also a useful place to practise car control.
Field Lane is the unusual one: a wet, muddy route with very little grip. A rally car can produce too much traction, so the BMW remains a good choice. Build speed before the start without arriving out of control, then maintain a useful angle while keeping the tyres away from the grass, where scoring stops. Link the smaller slides along the short straights and aim for roughly 45,000 points to earn all three stars.

The 993 Porsche 911 GT2 mid-drift. Using a manual transmission and turning off traction control is basically essential for these challenges.
Completing the Drift Zones also contributes plenty of bricks toward your Master Builder's House. Once the settings and car are right, the main challenge is keeping each drift connected without sacrificing too much speed.