Engine, suspension, brakes, tyres and more – we lay down the mods you really need on your car.
We spend countless hours talking about, working on and being alternately deeply enamoured and furious with our cars.
This got us thinking – of the manifold modifications we’ve made to our machines, which, if any, have actually improved our cars in measurable and appreciable ways?
Well, to answer that, we’ve put the eight must-do mods together, kind of like a tuner’s 10 commandments. Except there are eight.
1. Tyres
Okay, this seems a little conspicuous, we admit, but we do need to stress that even if we didn’t work for Toyo, and were posting to a forum on university study tips, we’d all list good-quality tyres as the best investment you could ever make.
Even though high-quality tyres are sometimes more expensive than a shipping container full of el-cheapo also-rans, consider one simple fact: tyres are your only contact with the road, unless you have very ill-fitting body panels, a loose muffler, or a passenger who chose the wrong moment to get out of the car.
2. Brakes
You might baulk at the cost of a serious set of brakes in the shop, but when you’re not a new addition to that SUV’s B pillar, you’ll know you invested well.
There’s debate across the internet about whether cross-drilled and slotted rotors are better than their solid counterparts.
Consider Formula 1 cars – they don’t have cross drilling, just the same sort of venting you find on the front brakes of almost every car sold today. What they do have are carbon ceramic discs and pads.
Now, these are horrifically expensive things to fit to your car, but they do come with a series of benefits. They’re touted as lasting 150,000 kilometres on a road car, which makes them a much more attractive investment.
Carbon ceramics can take more heat and get rid of it more efficiently than metal, are as tough as coffin nails and are half the weight of conventional steel discs.
This means huge benefits to ride quality and handling but for availability and price, traditional steel discs are still your best bet.
In any case, make sure you run only the best quality brake fluid, and invest in high quality (or even braided) brake lines too – they’ll improve the feel of the brake pedal underfoot.
3. Suspension
Installing springs with higher rates, aggressively tuned dampers and thicker anti-roll bars can compromise comfort and control on rough roads, so match them to the driving you’ll be doing. Forums dedicated to your specific car can offer suggestions, but a trusted mechanic is always a better bet to find the right balance.
We’ll include strut and body braces here, as they’re usually mentioned in the same breath. Strut braces even out suspension loads at the absolute ragged edge, so if you’re taking your car to the track, go for it. For regular road use, it may not be worth your money.
Other braces improve torsional rigidity, as do roll cages, which makes a lot of sense on the track but less when you’re trying to put your groceries in the back, in between some iron girders and scaffolding.
4. Wheels
Only three things truly matter when choosing new wheels for your pride and joy. They are fitment, weight and strength.
Fitment is paramount; you don’t want your wheels ruining the turning circle, fouling on body panels or suspension components or throwing out your suspension geometry.
Weight is the natural enemy of the car. Free of the unnecessary glut fitted at the factory for reasons of price, safety or simplicity, your car will accelerate and brake faster and corner better.
An easy way to lose weight hides in plain sight. By exchanging your stock rims for something lighter, you’ll immediately notice a more responsive ride, greater body control, and better handling, in that subjective way that can only be felt through your fingertips. Or, alternatively, through your knees, if you’re trying to tweet and drink cappuccino at the same time.
5. Servicing
It’s no secret that cars are severely complex bits of kit, so frequent and meticulous maintenance is vital.
When you’re using consumables such as coolant, oil and hydraulic fluid, it’s always your best bet to go for the highest quality. Seems almost redundant to mention it, but we’ve seen too many cars running cheap, heavily diluted coolant, horrible home-brand mineral oil and dodgy brake fluid, all in the name of saving precious little at the time of servicing.
6. Slim down
Weight, as we’ve said earlier, is the natural enemy of the car. So trimming some of the unnecessary fat should be the next item on your checklist.
Have a look at the junk you’re carrying around in your car. There are so many things adding weight, and sometimes air resistance, which you can remove at the flick of a screwdriver or socket set... or the swing of a hammer, if you’re not thinking things through.
Turf your roof racks, mudguards, spoilers and aerials – you’ll clean up the look and improve the performance of your car.
If you’re so inclined, there are a multitude of ways to shed extra girth from your car.
Power-operated, heated seats may be opulent, but these things can weigh upwards of 30 kilograms, compared to a lightweight racing bucket's 7.5 kilos. Carpet and soundproofing are dead weight, but ask your significant other before attacking the family wagon with a Stanley knife, as it’ll get mighty loud in the cabin without some insulation.
You can lose your stereo and back seats too, but again, consult the people you’ll be chauffeuring around before you toss them out. Er, the seats, that is.
This brings us to the thorny issue of the weight of the driver. Citing the benefits to driving performance as impetus for your significant other’s weight loss is purely at your own discretion and risk, but we venture that the consequences would be somewhat hilarious, if nothing else.
7. Gearbox, flywheel, differential
The gearbox – and connected drivetrain – can yield real improvements in acceleration, cruising, economy, control and enjoyment. A bit of a silver bullet, then.
Installing a multi-plate clutch increases the torque transmitted from flywheel to gearbox, and essentially wheels. It also decreases the inertia of the clutch, meaning it takes less torque to spin the clutch. Multi-plate clutches weigh less than their single-plate equivalents and usually take less effort to disengage and engage.
A short-throw shifter reduces the time spent changing gears, and yields a much more positive feel than stock gear shifters.
Adding a limited-slip differential will constrain the rotational speed of driven wheels so they can only rotate at similar speeds. This means more grip, better control, and more confidence that your car won’t need Jaws of Life in the very near future.
Flywheels act as a steadying force between your engine and your gears. Without them, driving would be as rough and unpleasant as a swan dive into concrete. Manufacturers tend to err on the side of smoothness, however, and often install flywheels that are heavier than necessary, so it’s possible to improve the responsiveness of your engine by installing a lightweight flywheel.
8. Intake and Exhaust
When it comes to air intake, keep it clean, cold, dry and free-flowing.
Why does air have to be cold and dry? Glad you asked. Cold air is denser than hot air, and dry air is denser than humid air. Dense air is a very good thing to put in your intake, because it contains more oxygen, a somewhat vital component of internal combustion.
For the exhaust, don’t believe the old wives’ tale that ‘you need back-pressure’. Have a look at any race car, ever. What do they have in common? The smoothest, shortest track from exhaust port to outside air. There are three absolutes for exhaust gases – keep them smooth, keep them hot, and get them out.
Kinks slow exhaust gases down, as does cooling, restrictions, baffles or going from regular-diameter pipes to a massive muffler of cannon-like proportions.
A thermally insulated exhaust keeps exhaust gases hot. Hot gas flows faster than cold gas. More flow equals less backpressure, which in turn equals less work the engine has to do to expel exhaust gases.
Finally, keep it legal, unless handing your wheels over to John E Law is something you’re keen to do.
Where to from here?
In reality, only your bank account, the laws of physics and the patience of your significant other limit the possibilities.
If your car is naturally aspirated, you can go for old school tuning or turn to forced induction. If your car is already turbo/supercharged, extra boost, along with camshafts and cooling to suit, will vastly increase power and torque. If your car is new, remapping the ECU can provide a performance increase, usually at the expense of any manufacturer’s warranty.
It can really keep going until you’ve spent as much on your pride and joy as you could have spent on a pair of Lamborghinis.
But for a car that is driven to excite, driven to delight and driven to perform, our eight-step program will put you on the right track.
