The Rules Around Modifying Your Car

Modifying cars is something that many people wish to do from the outset – why would you want a car that blends in with every other car on the road when you could have something that grabs people’s attention as you drive past? From sound systems to wonky wheels, Scrap Car Comparison guides you through the dos and donts in the world of vehicle modification.

But first, if your current set of wheels leaves much more to be desired than your modified dream, then why not get rid of it sooner than later, and with Scrap Car Comparison, that’s made as easy as it can get. You could find the best price in your area within 60 seconds with our online quote generator, and before you know it your car will be being recycled and disposed of with a certified Authorised Treatment Facility. Get started today and find out just how much your car could be worth. 

What are car modifications?

By their official definition, car modifications are changes ‘made to a vehicle so that it differs from the manufacturer’s original factory specification’. The majority of people make modifications to their car to improve either their performance or the aesthetic, and the most common of these are louder exhausts, tinted windows or beefed up audio systems.

Are car modifications illegal?

This is a tough one to answer as in many cases the answer can be both yes and no. For the most part, most modifications have the potential to be legal, providing you don’t go too far away from the original factory specification. For example, simply adding alloy wheels will not land you in any legal trouble, nor will carrying out an LPG conversion on your car, and, amazingly, neither will swapping your engine out – providing you inform the DVSA.

Some modifications are perfectly legal, providing you stay within reason. For instance, you are well within your rights to tint your windows, but if you go too dark or tint the wrong windows, you can expend some slaps on the wrist and fines heading in your direction. You’ll be fine so long as 70% of light can make it through the front windows, and the windscreen allows 75% of the light through.

If you’re modifying your sound system, exhaust or anything else that could result in your car being a little noisier, you’ll just need to make sure you’re considerate for other road users and those around you. If you’re deemed to be a nuisance, the police could seize your car, and if you are switching exhaust systems, you’ll need to ensure that it doesn’t make your vehicle louder than its category allows. If it does breach the decibel barrier, then you could receive an on-the-spot fine of £50 and be ordered to remove it.

What car modifications can I do?

There is a wealth of changes that could be made to a car, should you wish, all of which have their own unique positives and, of course, negatives. So, what can you do to your car? Well, here’s just a handful of the most common changes you can make:

  • Alloy Wheels – Quite a simple one here, and one that doesn’t really make much of a difference to the car overall, just be careful when parking, as there’s nothing worse than kerbing an alloy.
  • Bigger, and louder, exhausts – Want people to instantly think your car has more performance even if it doesn’t under the bonnet? Pop a big exhaust on. Often, when you see, or rather hear, ‘boy racers’ coming down the road, chances are they’re all bark and very little bite. Just beware though, if the new exhaust is too loud, you could get a £50 fine and find your car taken off the road until the offending exhaust is removed.
  • Tinted Windows – A popular choice for those after a little more privacy, tinted windows can be as dark as you like on the rear, but you’ll need to ensure front windows let in at least 70% of light, and the windscreen at least 75%. This is so your visibility is not obscured to the point it becomes dangerous. If yours are too dark, your car could be removed from the road until the tint is sorted, and in extreme cases you could find yourself in court over it.
  • Spoilers – The pros to adding a spoiler on to your car is that, at high speeds, you are offered greater stability and handling, and it immediately gives your car a more sporty look to it. However, if it is not secured safely, has sharp edges, or impedes your view, then expect to be instructed to remove it.
  • Lowering Suspension – One of the more advanced ways of modifying a car, and one that’s not technically illegal, but could well draw the attention of the police. If you have lowered your car, it must not have had any effect on the steering ability, nor can it have any impact on the height of your headlights. Only a competent mechanic should carry out the work on lowering suspension, and never cut or weld elements of your suspension, or you could be creating a death trap. It’s also worth bearing in mind that lowering your car could make speed bumps particularly tricky.
  • Sound systems – We’ve saved one of the most divisive for last. While it might be cool when you’re in the car in question being able to blast your music out as loud as your ears can take, there’s nothing worse than hearing that jarring “oonse oonse oonse” of drum and bass in the distance. Things to consider is you’ll be sacrificing boot space to get that subwoofer in, and if your music is so loud it’s considered to be causing ‘alarm, distress or annoyance’ to a member of the public, your car could be seized.

Will modifying my car affect my insurance?

Most modifications will result in your insurance premiums being higher as your car is regarded more of a risk when behind the wheel. This could be accident risk when adding performance upgrades as you’ll be expected to be driving faster, or it could be the risk of your car being broken into if you’ve added sound systems or DVD players. Safety features such as immobilisers, dashcams or telematics systems, however, could see a reduction in your premiums.

Don’t think you can get around it by not telling your insurers, however, as failure to inform them could result in your policy being invalid, meaning you would not be able to make a claim if needed. 

If I modify my car, will it decrease its value?

You might think that you’re making your car so much better than it’s drab original spec by adding that wicked sweet awesome Halfords bodykit, or by adding a speaker system that wouldn’t be out of place on the Pyramid Stage at Glastonbury, but chances are you’re actually seriously harming the resale value rather than improving it.

Even something as simple as adding a “powered by Fairydust” sticker, or eyelashes on the headlights (voted the UK’s most hated modification in a recent survey) could see potential buyers trying to slash your asking price by approximately £150, while more significant modifications such as extreme negative camber (‘wonky wheels’) or lowered suspension could see your value drop by as much as £300.

Do you have to declare car modification?

Any modification that takes your car away from factory standard must be declared to your insurers, whether they were made by yourself or they came with the car when you bought it, even if they had no bearing on the overall value. Failure to keep your insurers up to date with modifications could result in your policy being invalidated, and driving without a valid insurance policy is a crime in itself. You’ll likely find that a modified car pulls a higher insurance premium, and in that case it’s best to shop around. Some insurance companies offer bespoke modified vehicle policies, but it’s worth going in expecting to pay more than you would for a bog standard version of your set of wheels.

If your car is in need of some serious modification to get it to a working state, or perhaps you’re looking to get rid of a boring old car for something that you can modify, then Scrap Car Comparison is here to make the sales process as quick and stress free as possible for you. All you need to do is pick up the phone and provide us with your postcode and registration number and we’ll do the rest, and with collection agents operating across 99% of the country, we’ll even throw in a free collection to boot. Get started today and find out just how much your old car could be worth as scrap or salvage.

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