In this week’s Insider Guide, Episode 17, Yorkie065 will guide you through the essentials of your engine, ECU systems, and gearing.


This is the amount of fuel at the beginning of a race, beginning of a session, or when exiting the pit lane in non-race sessions.

Having more fuel will allow the car to run for longer but it will have a negative effect on performance due to the extra weight. Rule of thumb is always to ensure you have enough fuel to go the distance required, as extra fuel adds weight, and weight has a negative effect on performance.


The Boost Pressure allows control over the power produced by the turbo or supercharger.

Having a higher Boost Pressure will increase the amount of airflow from the turbo to the engine, thereby increasing the power. This, however, will also use extra fuel, increase engine wear, and potentially make the car difficult to handle due to turbo lag.

Decreasing the Boost Pressure will reduce the amount of airflow, thereby decreasing the power, fuel usage, and also helps reduce engine wear while making the car easier to drive when the boost comes in.

Make sure to find a balance for the session or type of race entered. For Qualifying, for example, turn up the boost for more performance. For an endurance race, running lower Boost Pressure for fuel strategy and engine longevity may be best. Higher boost pressures may also require extra radiator cooling to avoid engine overheating.


The Air Restrictor Diameter allows you to balance the car’s performance against other cars in the same class.

Lowering the Air Restrictor Diameter will decrease the amount of air getting into the engine and therefore reduce power. Increasing the diameter of the air restrictor will increase the airflow, increase power.

This is mainly used for Balance of Performance (BOP) purposes, but only applies to your own car.


The Radiator Opening determines the amount of airflow into the radiator to cool the engine. This is important for managing both engine oil and water temperature. Bigger radiator opening means more engine cooling, but comes at the cost of aerodynamic drag, and reduced downforce.

Find a balance for the track, conditions, and type of race entered. Cooler conditions will allow the radiator opening to be run at a lower, and at a more closed, value. Damaging the car where the radiator is located can also reduce its effectiveness. The chance of blowing the engine if the water temperature rises too high is also heightened.


The Engine Braking Map setting will determine how much the engine works in the deceleration of the car off-throttle. This works as a bit of a compensation where the ECU opens the throttle slightly to reduce the amount of engine braking.

This is largely a driver preference setting. Low values result in greater braking torque from the engine when off-throttle, which may be desirable to achieve a slight trail-braking effect without using the brakes. Higher values give less engine braking torque, which may be beneficial in certain high-speed corners to prevent changes in chassis balance when lifting off the throttle.

This does also have a slight effect on the amount of fuel used over the course of a lap.


The Final Drive Ratio adjusts the differential gear ratio, allowing the car to be dialled either toward acceleration or top speed. This ratio has an effect on all other gears.

Higher Final Drive Ratios allow more engine torque multiplication, increasing acceleration at the cost of a lower top speed. Lower Final Drive Ratios will give less wheel torque but will allow for a higher top speed.

Adjust the Final Drive Ratio so that the engine is just touching the rev’ limiter at the fastest part of the circuit. Too short a ratio means losing top speed. Too long a ratio means wasted engine power.


Adjust the individual Gear Ratios so that the engine stays within its power band for as much of the track as possible. Higher ratios mean more acceleration, and less top speed.

As a general rule, set first gear up for getting off the grid with maximum acceleration, or for ideal acceleration out of the slowest turn on a track. Then set top gear so the engine is near peak power on the longest straight.

For the gears in between, there are two approaches. For some cars, it can be beneficial to select gear ratios so that there is no shifting gear mid-corner, as the act of shifting can upset the chassis balance. This is less of an issue with modern, semi-automatic gearboxes, which mean ratios that give the best acceleration can be chosen: wider gaps for the low gears, which become closer the higher you shift up through the gearbox.


This allows for the adjustment of the red-line limit of the engine.

Increasing this allows for higher revs to be used in the engine, yielding more engine power at the cost of increased engine wear.

Set the rev’ limit to fit the type of race or session being run. Short races and qualifying sessions can sacrifice engine wear for the power increase. A lower rev’ limit is better for endurance races, to make sure the engine survives the distance.


This controls the amount of wheel slip allowed by the Traction Control system.

Higher values allow more slip, and are good for high grip situations: dry track, slick tyres, optimal weather.

Low values cut power at lower wheel slip, and can be beneficial in low grip situations such as a wet track, or when tyre wear must be managed closely.


This allows control of the strength of the Anti-Lock Braking System.

Increasing the value will make the system detect the wheels locking under heavy braking earlier, limiting the amount of tyre lock-ups, and retaining more cornering control for the driver. This is ideal for wet conditions on tarmac surfaces where the tyre is more sensitive to locking-up under heavy braking. Note: Increasing ABS strength does not automatically decrease the length of braking zones: in fact, it can make them longer as the system interrupts braking to a greater extent.

For loose surfaces, decreasing the ABS strength can help improve braking distances. This is because allowing the locking of the tyres will force them to dig into the surface, which stops the vehicle more quickly than if they were rotating on the surface of dirt, or deep snow, for instance.


Adjusting the Fuel Map allows the control of fuel-flow into the engine, affecting power output, and also the mileage that can run on a single tank.

Increasing the Fuel Map allows more fuel-flow into the engine, producing more power, and increasing acceleration. This, however, comes at the expense of higher consumption. Decreasing does the opposite: The fuel will last longer, but the engine will produce less power.

This is particularly useful for pit strategy, and reducing the number of refuelling stops required during a long race.

Now sit back, relax, and follow Yorkie065 as he takes you in-depth into setting up your gearing, tuning your engine for both performance and endurance, and how to best set the ECU.

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