Tuning Shop Guide

Following is a partial translation of the part shops menu. Also "GT Reference", pp.46-51.

If the part changes the engine power when installed, the current power and expected power are indicated at the lower-right corner of the screen, along with the price.

MUFFLER
Muffler & Air Cleaner
Sports
Combinaiton of a sports-type air cleaner and a muffler.
Semi Racing
Combo of an air cleaner using urethane sponge and a muffler for high-rev efficiency, best suited for large displacement turbo engine. When using with natural aspiration engine, the engine itself should be tuned properly.
Racing
Even more high efficiency air filter with air-funnel, and a straight muffler for racing cars. Best tuned for peak power. Note that since low-rev torque will be dropped, you should consider in accordance the overall characteristic of engine performance and gear ratio.
BRAKE
Sports Brake Kit
Better braking power as well as endurance, which is usable for endurance races. We're now on sale, so we'll change the brake fluid (DOT5) for free.
Brake Balance Controller
Controlls anti-lock brake system. With front is set higher, it will tend to be under-steer when braking, and with rear set higher, over-steer. Beware setting the rear too high, or you'll spin out easily.
ENGINE
Computer
Computer
Replaces an engine controller tuned for more power.
NA Tune
Stage 1
Adjusts ignition, valve timing, . Replaces exhaust manifold. Improves peak power without sacrificing low-rev torque.
Stage 2
Using high-comp piston, polished head-surface, replaces cam, valve spring, and polishes chamber port. Low rev torque is slightly reduced, but this is to achieve peak power at high rev. Also readjusts the engine management computer.
Stage 3
In addition to stage 2, piston, cam, valve, conrod, spring are replaced using different material. Since it is targeting for peak power, the power band is only in the middle rev.
Port Polishment
Port Polishment
Smoothes the air flow by polishing the chamber port, which improves engine response. Althogh the power improvement is tiny, this is crucial for NA engines.
Displacement Up
Displacement Up
Increases the engine displacement by increasing bore or stroke. Improves overall torque.
Engine Re-balance
Engine Balance Tune-up
Adjusts the weight balance of piston, crank shaft, etc., which reduces friction, allows more power and high rev. Includes reset of the rev-limitter.
TRANSMISSION
Gear
Sports
Closer gear ratio, best for natural aspiration engine.
Semi Racing
Even more closer gear ratio, best for hard-tuned engine. Note you need to change gear more often, which might be a loss for a wide-band torque engine.
Racing Support
Fully customizable.
Clutch
Single
Single-plate clutch.
Twin
Twin-plate clutch, ideal for large-torque high-power racing cars. Reduces the slipping of clutch when shifting up, which improves acceleration.
Triple
Triple-plate clutch, best for hard-tuned cars.
Flywheel
Sports
Ligher weight flywheel using chrome-molybdenum. Improves engine pick-up. Also acceleration is improved, but an engine with narrow torque-band may tend to stall in the upslope.
Semi Racing
Even lighter flywheel specifically for racing. Improves engine pick-up. Also acceleration is improved, but an engine with narrow torque-band may tend to stall in the upslope.
Racing
Super light flywheel for racing. Improves engine pick-up. Also acceleration is improved. But an engine with narrow torque-band may tend to stall in the upslope.
Propeller shaft
Carbon-composite propeller shaft
Light-weight propeller shaft made of carbon-composite. It is as much important as flywheel to improve acceleration.
TURBO
Intercooler
Sports
Intercooler lowers the temperature of air which was heated by pressurizing in Turbo Charger. Lowered temperature allows more air into chamber at same pressure.
Racing
Large capacity intercooler for racing. The engine response will be slightly worsened.
Turbo Kit
Stage 1
Turbine Kit I. With small turbo lag and quick response, this has good balance for any circuit.
Stage 2
Turbine Kit II. Compared to Turbine Kit I, low-rev torque is slightly decreased, but has enough power in mid- to high rev.
Stage 3
Turbine Kit III. Best tuned for 0-400m acceleration.
Stage 4
Turbine Kit IV. Tuned for peak power, ideal for max speed challenge.
SUSPENSION
Suspension
Sports
Sports suspension kit that can cover from street to circuits. Shock absorber (damper) can be set by 3 levels, and the camber angle is adjustable as well. The ride height is lowered by 2 centi meters.
Semi Racing
Suspension kit that can adjust ride height for medium-level drivers. Spring rate and damper rate are higher than Sports suspension. Ride height can be adjusted by millimeter. Damper rate is adjustable by 10 levels, and the camber angle is adjustable as well.
Racing Support
Shock absorbers, cambers, and spring rates are fully customizable. Shock absorbers has separate setting for extend and shrink each by 20 levels.
Stabilizer
Front
Soft
Stabilizer is to reduce the rolls, without changing the pitching.
Medium
It is also possible to reduce the roll by hardening the suspension, but that makes the pitching harder, and consequently makes the load-movement difficult, affecting brake performance. Stabilizer allows to reduce only the rolls.
Hard
Hardest of the stabilizers. Note the car is not neccesarily faster when using harder stabilizer. Choose the one that matches your driving style.
Rear
Soft
Stabilizer is to reduce the rolls, without changing the pitching.
Medium
It is possible to reduce the roll by hardening the suspension, but that makes the pitching harder, and consequently makes the load-movement difficult. Stabilizer allows to reduce only the rolls.
Hard
Hardest of the stabilizers. Note the car is not neccesarily faster when using harder stabilizer. Choose the one that matches your driving style.
TIRE
Tire
Semi Racing
Front-Hard / Rear-Hard
Best for endurance races.
Front-Hard / Rear-Soft
A combo of front-hard / rear-soft. Since the rear has more grip, the machine tend to under-steer. This is adequate when you want to improve oversteer tendency of high-power rear-wheel drive machines.
Front-Soft / Rear-Hard
A combo of front-soft / rear-hard. Since the front has more grip, the machine tend to over-steer. This is adequate for cars with under-steer tendency, such as FF cars.
Front-Soft / Rear-Soft
High-grip soft compounds for both front and rear. Best for sprint races.
Racing
Front-Hard / Rear-Hard
Slick tyres, which has no groove at all. Hard-compound for both front and rear. Hard compound has less grip than soft compound, but has more lastability. Best for endurance races.
Front-Hard / Rear-Soft
A combo of front-hard / rear-soft. Since the rear has more grip, the machine tend to under-steer. This is adequate when you want to improve oversteer tendency of high-power rear-wheel drive machines.
Front-Soft / Rear-Hard
A combo of front-soft / rear-hard. Since the front has more grip, the machine tend to over-steer. This is adequate for cars with under-steer tendency, such as FF cars.
Front-Soft / Rear-Soft
High grip soft compounds for both front and rear. Best for sprint races.

Note: Tyre-wearing can happen only in endurance races or 2-player battle.

OTHERS
Weight Reduction
Stage 1
Reduces the weight by removing unnecesary parts or replacing with lighter materials. Improves acceleration, cornering performance, brake performance, tyre endurance, and so on.
Stage 2
(same above)
Stage 3
(same above)
Racing Modification
Full racing-spec modification including the change of machine construction and material replacement. Includes drastic weight reduction, tread-width change, and fender modification for larger tyre. It does not include engine modification.

FUKUMOTO Atsushi
[email protected]