Vauxhall GTC Tuning

Tuning the Vauxhall GTC and best GTC performance parts.

We look at GTC tuning and outline the greatest modifications. Vauxhall GTCs are popular tuning projects and with a few sensible performance modifications you can dramatically maximize your driving enjoyment.

The GTC is a massive improvement over the Astra, but the handling and performance have much potential.

Bear in mind that the GTC is not a fancy Astra, the body and chassis are all different so this is more of an inspired by the Astra than a sporty version of it.

You can do a lot to improve the performance of your GTC with our step by step tuning tips. With the right mods your GTC can be transformed into a stunning project. Don't waste money, do your homework and follow our unbiased guides to each performance upgrade so you don't waste your money.

Tuning tips and articles

Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

Many GTC owners uprate the handling of their cars as a priority, this will certainly increase your enjoyment of the car. Drop the car by as much as 35mm and fit stiffer dampers, bigger drops will need other modifications in most instances.

Turning our attention to the GTCs engine we need to get a bit more power out of the top end.

Keep it looking standard but remove the badges to make an awesome sleeper!

The best power gains come from larger engine sizes. The more you start with the bigger the return on investment so engine swaps are good value mods for small engined cars.

Engine tuning mods.

The following modifications are usually performed by our members, decide how far you want to push your car before you begin.

Getting the correct grade of mods for your planned usage of the car is a time and money saver. Stage 3 motorsport mods just won't work well on the road and will make the car undriveable.

Stage 1 mods: Panel air filter,Remap,Alloy wheels,Sports exhaust,Suspension upgrade (drop 30-40mm),Lighter flywheel.

Stage 2 mods: Power clutch,Fuel injector & fuel pump upgrades,Fast road cam,Ported and polished head,.

Stage 3 mods: Adding or upgrading forced induction (turbo/supercharger),Sports gearbox,Competition cam,Engine balancing,Internal engine upgrades (pistons/head/valves).

Your aims when tuning should be a wide torque curve. You don't want all the power to be at the top end of the rev range unless you are creating a competition car.

The point of this article is to give a little insight into the world of car tuning performance parts and point you in the right direction, our forum is where you can ask for more detailed advice and tips on your project and all aspects of modding cars.

Fast road cams offer one of the biggest performance gains for your money as far as a single performance modification goes on a NASP engine. The intake and exhaust flow play a large part in your cars power band, but be careful here, getting this wrong can upset the idle and make the car impossible to drive in traffic.

You'd generally need to follow a camshaft upgrade with other mods and finish with a reflashed ECU to fully realize your gains.When pushing up the power you will need to pay attention to the fuelling. More power needs more fuel. Using higher octane fuel is another option if you find you are suffering from detonation or premature ignition on your Vauxhall project after fitting other mods. Uprating the injectors is another beneficial modification and will deliver sufficient fuel. A fuel pump will only deliver a finite amount of fuel, so you may need to uprate this if your injectors are demanding more fuel.


Intake and Exhaust Tuning.

Now we move on to the intake and exhaust and ensure proper flow through the engine. Contrary to popular belief there is generally a small power gain to be had by fitting an induction kit, they only become beneficial and are recommended after you increase the engines power to the point where the standard air intake box cannot cope!

For most GTC engines TorqueCars would suggest you just go with a washable panel air filter. On heavily tuned engines and turbo vehicles an induction kit will help release the power providing you address the problem of needing cold air.

Sports exhausts will certainly help air flow from the engine but avoid an exhaust that is too large or you could will reduce the flow rate. Stick to 1.5 to 2.5 inches for best results.

Getting the head ported and polished will assist in flowing more air into each cylinder. This is definitely a job for a professional with a flow bench.

A good heavy duty fast road performance clutch will help to keep that power going where it should. Never skimp or expect the standard clutch to cope. NASP engines do not achieve big power gains if you remap them, unless you have done extensive modifications. With turbocharged engines this is another story. A remapped turbo will give phenomenal power gains and fully release the potential power of the engine.

We've also seen some tuners toying with twincharging conversions and making some impressively high power hikes.

Despite the large cost involved adding forced induction to a NASP engine will give large power gains. Turbos are generally harder to add than a supercharger. It is more challenging to map a turbo as the boost comes on exponentially with rpm. It is easier to map a supercharger because the boost is correlating to engine speed on a linear curve. Alternatively you could fit water injection to cut down knock.

Alloy wheel upgrades.

As alloy wheels are less heavy they improve performance and they can help to cool the brake disks. Please note that although they can look cool on the GTC large alloy wheels will actually decrease your performance. The larger you go the lower your acceleration will be - this to the change in your effective final drive ratio. Although some people have gone larger than this without issues we would stick to a 16 inch rim size as the maximum.

For more information on Tuning your car please join us in our friendly forum where you can discuss GTC options in more detail with our GTC owners. It would also be worth reading our unbiased Vauxhall tuning articles to get a full grasp of the benefits and drawbacks of each modification.

Please help us improve these tips by sending us your feedback in the comments box below. We love to hear what our visitors have got up to and which mods work best for them on each model of car. Comments are used to improve the accuracy of these articles which are continually updated.

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