Tuning can mean a lot of different things to different people. Some see it as enhancing the exterior styling, others as improving handling. But for most of us, tuning is regarded as improving the overall performance figures from a stock engine. This should be done in stages, where horsepower and torque numbers are increased incrementally. In addition, it needs to provide a balanced vehicle. You don’t want an overpowered engine sitting on a chassis that just can’t handle all the added grunt.
Why Tune Your Car?
Minor and inexpensive tunes are a prelude to bigger performance gains later on. Every car, regardless of the engine displacement and fuel type, can be tuned, whether you have an Opel, Seat, Alfa Romeo, BMW or Audi. You can check your owners manual just to be safe beforehand and if you lost it, you can easily find it online, here is an example of an Alfa Romeo manual.
Countless daily runabouts powered by smaller diesel engines are tuned for better efficiency. The already low consumption figures are cut even further, meaning cost savings as fuel prices go up. In addition, cars with little feedback from the wheel can get a better feel and response, so drivers feel more confident and safer as a result. The ultimate goal of a tune, however, is crunching more power out of the engine. Stock engines are shy little things that need some encouragement to reveal their full potential. By fitting a few performance parts, and balancing everything out, cars can reach almost double the output. And all that power is available earlier on in the rev range.
Tuning is a bit like building a house. You start from the foundations and work your up, adding things as you go along. Though not set in concrete, tuning stages begin with the chassis and bodywork and end deep inside the engine. This brings us to tuning stages – often described as stage 1, stage 2 and stage 3 tunes.
The easiest and fastest upgrade is an ECU remap. This changes the air/fuel ratio, timing and turbo response. Computers connect to the car’s OBD port with custom settings to suit your driving style. Modifications can be subtle or extreme, and this too is offered in stages or levels. A mild ECU remap will improve fuel consumption, while also releasing a few hidden bhp. The benefits are that the engine also pulls from lower revs, with the increase in torque. More pronounced ECU settings require changes to the stock exhaust, to provide for better airflow, along with better air intakes. Here there are plenty of options, and the goal is to give the engine more breathing space. Turbocharged cars will see a substantial increase in power.
Not taking things overboard is the essence of a balanced ECU tune. Too much and you risk losing power higher up, with the engine losing puff as it reaches the redline. This can also affect engine longevity and increase wear.
Stage 1 tunes can be done to the suspension and the exterior styling. Here the aim is to get better handling. Parts that are swapped out include the stock shocks and struts for something stiffer (and some level of adjustment) to set the car lower and reduce drag. Cornering and grip will be improved with the centre of gravity pushed lower. External bodywork, like spoilers, skirts, wings and diffusers, channel airflow under and over the car to increase downforce, and this sticks the car to the road. These also shed some weight, and make the car easier to flick around. To get the best out of the work done by exterior parts you’ll want grippier low profile tyres, set on tough but lightweight alloys. Any increase in power also means you need to upgrade to bigger brake rotors and callipers with more bite.
There’s no fine line between tuning stages. Stage 2 though starts to get more serious with turbochargers, camshafts and fuelling. Air intakes with bigger filters in stage 1 can handle more air, and this is where a turbine comes into the picture. You can modify a stock turbo with things like boost controllers and electronic wastegates to push more air in, or swap it for bigger turbo that can also spool faster. There’s also the possibility of combining turbos in biturbo setups. This will force air at any revs, so there’s linear acceleration, and no turbo lag. Or adding a turbo to a naturally aspirated engine. Throwing an intercooler in the mix will see the engine suck more air in, and at cooler temperatures.
More air means more fuel. Changes to stock injectors will see more fuel squirted in the air/fuel mix and at higher pressures. To do so you will also need to upgrade the fuel pump. And to get better timing, look for performance camshafts with some overlay and stiffer valves as well as beefier spark plugs. Some tuners also port and polish cylinder heads, often by widening the exhaust ports, and fitting a bigger gasket.
If you’ve reached stage 3, then you’re getting deep into the engine block. Stage 2 power increases require that power to be transferred through the pistons, connecting rods and crankshaft to the flywheel and transmission. Opting for lightweight yet robust forged pistons and conrods, as well as a treated and machined (forged or billet) crank, will see RPMs increase substantially. The higher the rev range, the more power. Engines able to sustain those speeds will undoubtedly be under more stress, so choose quality performance parts from reputed brands. Here, tuners also make changes to the transmission, by including a lighter flywheel, uprated clutch plate and stiffer pressure plate to get all that power down to the wheels. Balancing out excess rotational pull from the crank is done by fitting a dampener to the front pulley.
What to Expect?
Expectations can be high but are limited by the stock engine and your budget. There’s just so much power modifications can release from the stock parts, until this turns into a complete engine rebuild. Also, there’s the risk of increased wear to the point that parts fail and the engine is ruined. Pairing high-performance parts cautiously are key here and a little upfront knowledge helps to avoid common mistakes.
Stage 1 modifications are easier on the pocket and can bring a smile to your face from an already capable stock engine. Of course, performance gains will depend on what you change and on which engine. Think in the lines of Nissan’s VR38 DETT in the GT-R, Honda’s KC20 in the Civic Type R, or BMW’s N54 and N55 in the M cars, and their younger sibling, the B58 in the Z4 and Toyota Supra. These are just some of the engines tuners enjoy modifying. There’s already a healthy wisp of performance even in stock form. But going further, with changes to the internals in stages 2 and 3 can see some serious numbers on the dyno. And a bigger hole in the back pocket.