Dodge Challenger SRT Demon Tuning Guide — Best Setup for FH6
Class Range: A - S2 | Base HP: 840 | Drivetrain: RWD | Weight: 1,930 kg | Best Class: S1 (Drag)
The Dodge Challenger SRT Demon is the spiritual opposite of every European hypercar. Where the Jesko is a surgical instrument, the Demon is a sledgehammer. 840 horsepower from a supercharged 6.2-liter Hemi V8 that sounds like it's actively trying to tear itself apart. This is the car you buy when you want to do one thing — go fast in a straight line — with maximum theater.
And here's the thing: it's terrible at everything except drag racing. The handling is atrocious, the brakes are overwhelmed by the weight, and the transmission feels like a tractor. But on a drag strip, the Demon is the king of S1 class. Tuning the Demon is all about the launch — if the car doesn't hook up in the first 60 feet, you've already lost.
Best Tuning Setups by Class
S1 (900) — Drag Strip King
The ultimate S1 drag build. Soft rear springs for maximum squat, full diff lock, tall rear ride height creates wedge for weight transfer.
S1 (900) — Roll Racing
For highway roll racing. Slightly firmer rear to prevent excessive squat at 300+ km/h.
Key Tuning Parameters
Engine & Power
The supercharged Hemi provides instant boost — no lag to manage — but the supercharger consumes significant engine power just to turn the blower. Upgrading to a race supercharger adds boost pressure but also increases parasitic loss. I prefer keeping the stock supercharger and spending PI on weight reduction and tires. The engine responds extremely well to camshaft upgrades — the stock cam leaves 50-80 hp on the table.
Suspension & Handling
Drag suspension is backwards from circuit suspension. You want rear springs as soft as possible without bottoming out — 250 lb/in is my starting point. Front springs should be stiff (600-650) to prevent the nose from lifting. Rear ride height should be 3-5 clicks higher than front for permanent forward rake. Bump damping: extremely soft rear (2-3), stiff front (7-8).
Gearing Strategy
2nd gear is the money gear — it should take you from ~50 km/h to ~120 km/h, covering the bulk of the quarter-mile. You should cross the finish line at redline in 4th gear. If you're grabbing 5th before the traps, your final drive is too short.
Common Tuning Mistakes
- Circuit-style suspension on a drag build. Stiff all around = zero weight transfer = no traction.
- Too much rear tire pressure. 18-20 PSI gives a bigger contact patch for launch grip.
- AWD swap without gearing changes. AWD adds drivetrain loss — shorten final drive to compensate.
| Problem | Fix |
|---|---|
| Wheelspin through 1st and 2nd | Lower rear tire pressure to 18 PSI, soften rear springs 50 lb/in, throttle modulation until 3rd gear |
| Car bogs off the line | Shorten 1st gear, increase launch RPM to 2,800, check cold tires |
| Nose lifts too much under acceleration | Stiffen front springs 75 lb/in, lower rear ride height 3 clicks |
FH6 Tuning Tips for This Car
When tuning this car in FH6, start with the suspension and tires before touching the engine. Most players add power first and wonder why the car is undriveable. The optimal build order is: race tires, race suspension, race brakes, weight reduction (stage 1-2), then engine upgrades. The PI budget should be split roughly 40% handling, 40% power, and 20% drivetrain. For road racing, prioritize corner exit grip over top speed. For speed zones, sacrifice some handling for more power. The most common mistake is over-upgrading — leaving the car at 80-85% of max PI often gives the best balance and leaves room for event-specific tuning adjustments. Test every upgrade increment, not just the final build.