Tuning Tips

Build the chassis first. Add power last.

FH6 punishes the older Forza habit of dumping PI into horsepower first. Tighter circuits and touge passes reward cars that turn in cleanly, brake without locking, and put down what they've got. Horsepower without grip just spins the rear tires off the line.

The fastest FH6 builds aren't the highest-HP builds. They're the cleanest chassis with just enough power to hit the class ceiling.

Road Racing

Tire compound by class

• D / C: stock or street
• B: street default, sport on tighter tracks
• A: sport or semi-slick, depending on what fits
• S1 / S2 / R: race slicks mandatory

Drivetrain meta

AWD dominates S1 and S2. The grip out of corners pays for the PI cost every time. A class and below, RWD is still competitive. FWD is viable on tight technical layouts but rarely the optimal pick.

Build order

1. Front tire grip (compound and width)
2. Brakes
3. Suspension (race springs, race ARBs)
4. Weight reduction
5. Drivetrain (race diff, race trans with 6-7 gears)
6. Power. Only enough to hit the class ceiling.

Tire stagger

RWD wants wider rear than front. Typical S1 split: 285 front, 325 rear. FWD runs equal width or slightly wider front. AWD usually equal.

Testing

Tunes don't transfer between track types. Test on the actual layout you'll race. Rivals events give you a consistent track and weather for repeatable lap times.

Drift

RWD is the standard for drift. AWD drift works mechanically but is uncommon in the drift community.

Engine swap philosophy

Pick an engine where horsepower and torque are close together. Throttle response wins over peak power. Torque-rich V8s work great. Wild V12s kill control because there's too much power to manage at angle. High-RPM screamers (V10s, racing I6s) are perfect for road racing and terrible for drift.

Engine weight matters. A heavy block destroys front grip and makes the car push wide. A torquey I6 in a Silvia is one common build.

Drift parts

• Drift compound tires
• Dedicated drift 4-speed transmission, or race trans with long gearing
• Race diff with acceleration at 90-100%
• Wider rear tires
• Spoiler for stability at angle
• Aggressive weight reduction within class

Drag

Drivetrain

AWD launches harder and wins on the clock. RWD is the classic drag experience: bigger weight transfer, smokier launches, real burnouts, and more time to manage off the line. RWD builds typically run 0.2-0.4 seconds slower than equivalent AWD builds but are more engaging to drive.

RWD drag specifics: max rear tire width within PI, rear weight bias if the chassis allows, very soft rear springs, and patience with the throttle off the line.

Tire pressure

Community baseline is 55 PSI front, 15 PSI rear. Low rear gives a larger contact patch for launch. High front gives lower rolling resistance. These numbers are drag-only. Way too aggressive for any other event type.

Suspension

Soft springs front and rear. Front softness lets weight transfer rearward on launch. Rear softness absorbs the transfer and plants the rear tires.

Transmission

Race transmission. Gear count depends on class and strip length. Stock 4-speeds run out of revs above C class. Quarter mile builds typically use 5-7 gears. Half mile and high-class builds benefit from 7-10 gears to keep the engine in its powerband.

Gearing

1. Top gear all the way right on the gear ratio graph.
2. Bring lower gears up to meet it. Curve should look evenly distributed.
3. First gear: bogs off the line? Shorter. Spins helplessly? Longer.
4. Tune intermediate gears so you cross the finish line at the top of your final used gear, not bouncing off the limiter and not already shifted out.

Quarter vs half

• Quarter mile: aggressive 1st, short top, max launch focus.
• Half mile: more mid-range emphasis, longer top for trap speed.

Class Nuances