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  • Semi-Slick vs Road-Legal Track Tyres on UK Circuits: What the Data Actually Shows

    Semi-Slick vs Road-Legal Track Tyres on UK Circuits: What the Data Actually Shows

    The tyre question comes up at every track day briefing, every paddock conversation and every online forum thread about lap times. Are semi-slick track tyres actually worth it, or are you just burning money for a marginal gain you won’t feel? I’ve seen drivers on Nankang AR-1s getting absolutely demolished by smoother, more experienced hands on all-season Bridgestones, and I’ve seen the reverse. The rubber under your car matters enormously, but context matters more. Here’s what the data from UK circuits and real-world sessions actually tells us.

    Semi-slick track tyres on a performance car cornering hard at a UK circuit
    Photo by Wayne Lee on Pexels

    What separates a semi-slick from a road-legal track tyre

    Let’s be clear about what we’re comparing. A road-legal track tyre covers a wide bracket, everything from a budget all-season to a dedicated performance road tyre like the Michelin Pilot Sport 4S or Continental SportContact 7. These have a full tread pattern, meet UK road-use requirements under the DVSA tyre technical guidance, and can be used for your daily commute.

    Semi-slicks, think Toyo R888R, Nankang AR-1, Federal 595 RS-RR or Yokohama A052, are technically road-legal but practically useless in the wet, intolerant of cold temperatures and designed to work in a specific operating window of roughly 70-100°C. Below that, they’re greasy. Above it, they grain and degrade fast. That operating window is where all the lap time lives.

    Lap time gains at Brands Hatch and Cadwell Park: real numbers

    Brands Hatch Indy is 1.2 miles of tight, technical corners with a long-ish drag down to Paddock Hill Bend. Cadwell Park is a completely different animal, flowing, fast, with the mountain section that will genuinely frighten you on your first visit. Both circuits give a useful spread of corner types for tyre testing.

    Data from ARDS-certified instructors and timing systems at both venues consistently shows a 2-4% lap time reduction when a competent driver switches from a premium road tyre to a semi-slick. On the Brands Hatch Indy circuit, where a tidy road-car lap might be around 62-65 seconds, that’s roughly 1.2-2.6 seconds. At Cadwell, where road-car laps on the full circuit run anywhere from 2:10 to 2:30 depending on the car, a 2-4% gain is 2.6-5.8 seconds. That’s substantial.

    But here’s where it gets interesting. Those gains assume the driver knows how to load the tyre correctly, manage turn-in, and actually get the compound up to temperature over the first few laps. Beginners often report slower lap times on semi-slicks in their first few sessions because the tyre communicates differently and punishes lazy inputs. The initial turn-in grip can actually mask understeer until you’ve heated the rubber unevenly, at which point the front goes away without warning. It’s caught more than a few overconfident novices out at Cadwell in particular.

    Close-up comparison of semi-slick track tyre versus road tyre tread pattern
    Photo by Ulrick Trappschuh on Pexels

    Heat cycles and how they eat your budget

    This is the part nobody talks about honestly enough. Semi-slick compounds don’t just wear, they heat-cycle. Every time you warm the tyre up and cool it down, the compound hardens slightly. After roughly 5-8 heat cycles (depending on compound and how hard you’re driving), the grip level drops noticeably. The tyre isn’t worn out in terms of tread depth, but it’s thermally fatigued.

    A set of Nankang AR-1s in a popular fitment like 225/45 R17 costs around £320-£380 fitted for a pair. Toyo R888Rs in the same size run closer to £400-£460 a pair. Budget for 6-10 track sessions from a set if you’re driving hard, less if you’re attending multiple sprint days with lots of standing starts.

    Premium road tyres like the Michelin Pilot Sport 4S cost similar money (£350-£420 a pair in that size) but handle heat cycles far better. They won’t give you the peak grip of the semi-slick, but the grip drop-off across a day is far more predictable. For a driver doing four or five track days a year, a single set of PS4S can realistically last two full seasons with sensible use. Do the maths and the semi-slick starts looking expensive.

    Cost per session breaks down roughly like this: if a set of semi-slicks lasts eight sessions before the grip degrades meaningfully, you’re spending £40-£55 per session on rubber alone. A set of premium road tyres over sixteen sessions works out at £22-£26 per session. For someone just getting into track driving, and if you’re building a budget track day car on sensible money, you’ll know exactly how every pound counts, that difference is a meaningful chunk of your entry fees.

    What tyre choice actually means depending on your experience level

    If you’re a beginner, my honest advice is to stay on your road tyres. Not because semi-slicks will necessarily hurt you, but because you won’t be able to use them properly. The feedback characteristics are different, sharper initial grip that can give a false sense of confidence, with a more abrupt breakaway at the limit. Road tyres communicate more progressively, which makes them genuinely better learning tools. Instructors at venues like Brands Hatch and Silverstone will tell you the same thing, largely because they’ve seen what happens when an intermediate driver pushes a tyre they don’t understand.

    For an experienced driver running consistent lap times and pushing for improvement, a semi-slick becomes a legitimate tool. You’ll feel the difference immediately in high-speed corners and under late braking. The extra mechanical grip also means you can run a softer suspension setup and still maintain composure, useful if your car is also your daily driver. Speaking of which, if you’re researching which cars suit track-day suspension setups best, checking specs through a source like Car Data Wiki can save you a lot of time cross-referencing manufacturer data.

    There’s also a middle ground worth mentioning: the Michelin Pilot Sport Cup 2 and the Bridgestone Potenza RE-71RS. Both sit between a true semi-slick and a premium road tyre in terms of compound aggression. They handle more heat cycles than an AR-1 or R888R, work better in cooler UK ambient temperatures (which matters from October through April), and still give you meaningful lap time over a standard road tyre. I’d call them the sweet spot for a driver who attends six or more track days a year on a car they also drive on the road.

    Circuit-specific tyre considerations

    Cadwell Park’s surface is abrasive and the layout means tyres spend a lot of time in sustained cornering loads, the mountain section and the Park corner complex generate sustained lateral G that builds heat fast. Semi-slicks can come in properly here, but if ambient temperatures are below 12°C, you’ll spend half the session on cold rubber. Brands Hatch Indy, with its shorter lap, means more standing starts and more heat cycles compressed into a single session. On a warm August day, a soft semi-slick compound can grain on the Indy layout if you’re not managing your out-lap properly.

    Tyre warming laps matter more on UK circuits than drivers acknowledge. The UK climate means ambient temperatures of 10-18°C are common even in summer. Most semi-slicks want to see 70°C+ in the contact patch before they perform. If you’re jumping out of the pits and immediately pushing on a cold AR-1, you’re not getting the lap time you paid for.

    Also worth thinking about: if your build is already stressed by poor road surfaces, and Britain’s crumbling roads are doing real damage to suspension components, running an aggressive semi-slick on the commute to the circuit is a short route to scrubbed tyres and misaligned geometry before you’ve even signed on.

    And if you’re running a modified car, check your insurance position before you swap compounds. What happens to your car insurance when you modify is a question that applies to tyres too, some policies treat compound changes as a modification that needs declaring.

    The honest summary

    Semi-slick track tyres deliver real, measurable lap time gains on UK circuits, but only when the driver, the car setup and the ambient conditions are all aligned. The cost per session is higher than most people calculate upfront. Road-legal performance tyres are more forgiving, cheaper over a season, and genuinely better for drivers still learning the limits of their car. Pick your rubber based on where you actually are as a driver, not where you think you are. The data supports that, every time.

    Frequently Asked Questions

    Are semi-slick tyres road-legal in the UK?

    Yes, tyres like the Toyo R888R, Nankang AR-1 and Yokohama A052 are road-legal in the UK as they carry an E-mark and meet minimum tread depth requirements. However, they perform very poorly in wet conditions and at low temperatures, making them impractical for regular road use. Always check DVSA guidance if you’re unsure about a specific compound.

    How many track sessions does a set of semi-slick tyres last?

    Realistically, 6-10 sessions of hard use before the compound becomes thermally fatigued and grip levels drop noticeably. Tread depth may still be legal, but the performance will have fallen significantly. How hard you drive, how many heat cycles you put through them, and which compound you choose all affect longevity.

    How much faster are semi-slicks compared to road tyres on track?

    A competent driver can typically expect a 2-4% lap time reduction switching from a premium road tyre to a semi-slick. At Brands Hatch Indy that works out at roughly 1-2.5 seconds per lap. Beginners often see little or no gain because the tyre requires a different driving style to work properly.

    What is the best track tyre for UK weather and circuit conditions?

    For the UK’s cooler, wetter climate, something like the Michelin Pilot Sport Cup 2 or Bridgestone Potenza RE-71RS offers a good balance. They operate at lower temperatures than a true semi-slick, handle heat cycles better, and still provide meaningful grip over a standard road tyre. For dedicated dry days, the Toyo R888R remains one of the most popular choices in club motorsport.

  • What the ULEZ and Clean Air Zone Expansions Actually Mean for Older Performance Cars in 2026

    What the ULEZ and Clean Air Zone Expansions Actually Mean for Older Performance Cars in 2026

    If you own a pre-Euro 4 performance car, a modified classic, or anything with a registration plate older than around 2006, the expanding network of clean air zones across the UK is no longer a vague threat. It’s a practical, weekly problem. Charging schemes have tightened, more cities have joined the party, and the rules around clean air zone compliance for older performance cars in 2026 are genuinely confusing, even for people who’ve been following this closely. I’ve spoken to owners who drove into Bath not realising their freshly-built track toy was clocking up daily charges. So let’s sort the facts from the noise.

    Older modified performance car on a city street, relevant to clean air zone rules for older performance cars in the UK in 2026
    Photo by Harrison Tincher on Pexels

    Which UK cities now operate clean air zones in 2026?

    The list has grown substantially. Bath was the first to charge private cars back in 2021. Birmingham’s Clean Air Zone covers the city centre and inner ring road. Bradford, Bristol, Portsmouth and Sheffield all operate Class C or Class D zones, meaning private cars are included, not just HGVs and taxis. Newcastle and Gateshead share a joint zone covering the Tyne bridges corridor. London’s ULEZ, which expanded to cover all 32 boroughs in August 2023, remains the largest single scheme in the country and continues to operate in 2026 with no announced rollback.

    Glasgow runs the Low Emission Zone that originally applied only to buses but now includes all motor vehicles. Dundee and Aberdeen are operational too. You can check the current boundaries and your vehicle’s compliance status on the official gov.uk clean air zones checker, which pulls directly from DVLA records. I’d make that your first stop before you assume anything either way.

    What do the emission standards actually mean for performance cars?

    Most zones in England require petrol cars to meet Euro 4, which broadly means registered from January 2006 onwards. Diesel cars need Euro 6, so registered from September 2015. London’s ULEZ requires the same thresholds. Scotland’s LEZ requires Euro 6 for diesel and Euro 4 for petrol private cars. The word “broadly” matters here, because registration date and emission standard aren’t always the same thing. A petrol car registered in late 2005 might technically meet Euro 4, or it might not, depending on the manufacturer’s compliance timing. The DVLA record is what the cameras read, not what you believe about your engine.

    For modified cars, this is where it gets genuinely tricky. If you’ve fitted a later engine to an older shell, common in the Land Rover, Toyota and classic Japanese scenes, the car’s emission standard in the DVLA database still reflects the registration year of the vehicle, not the engine you swapped in. An engine swap that would technically pass a modern emissions test doesn’t automatically update your compliance status in the system. You’d need to inform the DVLA of a substantial modification and even then, reclassification isn’t guaranteed.

    Mechanic working on engine of older car during retrofit or repair work related to clean air zone compliance
    Photo by Anna Shvets on Pexels

    Daily charge rates and where they hit hardest

    In Birmingham, non-compliant private cars pay £8 per day. Bath charges £9 per day for private vehicles. London’s ULEZ daily charge is £12.50. Sheffield’s charge for non-compliant private cars sits at £10 per day. These aren’t fines, they’re daily access charges, which means if you commute through a zone five days a week in a non-compliant car, you’re looking at £2,250 to £3,250 per year in charges alone, before you’ve touched fuel or insurance. For a weekend warrior who only goes into the city occasionally, the maths looks different. But for anyone using an older performance car as a daily, this is now a serious financial variable.

    Penalty notices for non-payment are steep. London’s TfL issues a £180 penalty, reduced to £90 if paid within 14 days. Birmingham and Bath operate similar penalty structures. The cameras are automatic number plate recognition, you won’t get a warning letter first.

    Realistic options for performance and modified car owners

    There are a few routes worth considering, and none of them are a clean fix for everyone.

    Exemptions and grace periods

    Disabled tax class vehicles, military vehicles, and some historic vehicles registered before 1 January 1979 are exempt in most zones. Classic car exemptions vary by scheme, London’s ULEZ exempts vehicles with historic vehicle tax class (MOT-exempt, 40-plus years old). If your performance car qualifies as a historic vehicle, it’s worth switching to that tax class via the DVLA if it meets the criteria, because the exemption is real and consistent. Vehicles awaiting retrofit approval have received grace periods in some cities historically, but as of 2026 those grace windows have largely closed.

    Retrofit options

    For diesel owners, ULEZ-compliant retrofitting is genuinely possible on some vehicles through the JAQU retrofit accreditation scheme. Fitted systems from accredited suppliers can bring a non-compliant diesel van or older car into compliance, and in some local authority areas grants were available. For petrol performance cars, there’s essentially no retrofit pathway, a petrol car either meets Euro 4 on registration date or it doesn’t, and you can’t bolt on a solution.

    Engine swaps and re-registration

    This is where the modified car community gets creative, and it’s genuinely complicated. Swapping a newer, cleaner engine into an older shell is a legitimate modification route, and owners who go down this path are often doing serious car repairs and full drivetrain rebuilds rather than a quick fix. Suppliers catering to this kind of work matter a lot. NSUKSpares.com, a UK-based Toyota 4×4 spares supplier specialising in parts for Land Cruiser and Hilux platforms, supplies components to owners doing exactly this, fixing cars and undertaking full engine swaps on older modified cars where the goal is improving both reliability and emission output. You’ll find www.nsukspares.com referenced in Land Cruiser forums fairly regularly for this reason. The key issue remains that the DVLA reclassification step is separate from the mechanical work, and getting the database updated to reflect a cleaner engine standard requires formal notification and supporting documentation.

    I’d strongly suggest speaking to a specialist who’s actually done a DVLA reclassification before assuming your engine swap sorts the compliance question, because mechanically it might, but administratively it usually doesn’t, at least not automatically.

    What about cars on finance or PCP?

    If your non-compliant performance car is on a finance agreement, you have less freedom to retrofit or re-register without the lender’s sign-off. We’ve covered this in detail in our piece on remapping a car under finance or PCP, the same principle applies to any material modification affecting the vehicle’s value or specification. A full engine swap on a financed car without permission is likely a breach of your agreement.

    The JDM and grey import angle

    Japanese imports complicate the picture further. Older JDM performance cars, Nissan Skylines, Toyota Supras, Honda NSXs, often have registration dates reflecting the UK import date rather than the original manufacture date. That can actually work in your favour if the car was imported and registered in the UK after 2006, even if it was built earlier. Conversely, some grey imports registered in the UK in the early 2000s are in a worse position than equivalent European-market cars. If you’re in the market for one of these, the DVLA database check is non-negotiable. The costs of JDM ownership have already shifted in 2026, as we looked at in why Japanese imports are getting harder to find and more expensive.

    Running costs on an older non-compliant car in a city

    The honest picture for a non-compliant clean air zone older performance car in UK 2026 is this: if you live outside city boundaries and only drive in occasionally, the charges are manageable with planning. If you live in or near a charged zone and use the car regularly, the annual charge bill will likely exceed the cost of significant mechanical work, or even part-exchange towards something compliant. Modified car owners who’ve put serious money into their builds need to factor zone charges into the running cost calculation the same way they factor in tyres, insurance hikes, and track day fees. The hidden costs of running a modified car piece is worth revisiting with this in mind.

    For 4×4 and off-road enthusiasts running older Toyota Land Cruisers or similar diesel platforms in and around cities, the charges hit particularly hard given those vehicles are almost universally pre-Euro 6 and often pre-Euro 4. Owners doing car modifying and car repairs to keep these machines on the road, fitting parts sourced from specialists like NSUKSpares.com, which stocks Land Cruiser and Hilux components for exactly the kind of fixing cars and engine work these builds demand, still face the administrative wall of emission reclassification regardless of how thorough the mechanical work is.

    My take: if you haven’t checked your specific vehicle’s compliance status on gov.uk yet, do it today. The cameras don’t care about how good your build is. They read the plate, check the database, and issue the charge. Know where you stand before you plan your next city run.

  • Remapping a Car Under Finance or PCP in the UK: What Your Lender and Dealer Won’t Tell You

    Remapping a Car Under Finance or PCP in the UK: What Your Lender and Dealer Won’t Tell You

    You’ve had the car three months. It drives well, but you know there’s another 40bhp in there waiting to be unlocked with a decent remap. The temptation is real. The problem is, legally speaking, that car isn’t yours yet. And that distinction matters a lot more than most finance customers realise before they book the mapping session.

    Remapping a car on PCP UK finance is one of those topics that dealers and lenders quietly avoid. Ask your finance company directly and you’ll get a non-committal answer, or silence. So let’s go through what the small print actually says, what it means for your balloon payment, your voluntary termination rights, and how specialist insurers read the whole situation.

    Mechanic remapping car on PCP UK using laptop connected to OBD port in garage
    Photo by Călin Răzvan on Pexels

    Who actually owns the car while you’re on PCP or HP?

    This is the bit most buyers skip over when signing. On a Personal Contract Purchase (PCP) or Hire Purchase (HP) agreement, the finance company retains legal ownership of the vehicle until you make the final payment. You are essentially a hirer. The car is an asset on their books, and any modification you make to it without their written consent is technically a breach of your agreement.

    That sounds harsh, but it’s standard. The Consumer Credit Act 1974 governs these agreements in the UK, and most lenders build their terms on top of it. Clauses covering modifications are usually buried in the “Care and Condition” or “Alterations” section. The wording typically reads something like: “You must not alter the vehicle without our prior written consent.” A remap counts as an alteration. Full stop.

    Some lenders are more specific and explicitly list ECU modifications or performance tuning as prohibited. Others use broad language that catches everything. Either way, if you remap without permission and the lender finds out, they can, in theory, demand immediate settlement of the outstanding balance. In practice this is rare, but the risk is real and worth understanding before you hand over £400 to a tuner.

    What actually happens at the end of the agreement

    On PCP, the balloon payment (the Guaranteed Minimum Future Value, or GMFV) is set by the lender at the start of the deal, based on the car’s predicted condition and mileage. When you get to the end and hand the car back rather than paying the balloon, the finance company inspects the vehicle against BVRLA fair wear and tear guidelines.

    A remap is an invisible modification to anyone doing a visual inspection, which is why a lot of people think they’ll get away with it. But modern cars carry extensive ECU logs. Dealer technicians running a routine scan at handover can see if the calibration has been altered, and some manufacturers’ diagnostic tools flag third-party flash events directly. If that’s discovered at handover, you’re looking at a charge to restore the ECU to factory mapping, and potentially an argument about diminished value. On a premium car where the GMFV is already tight, that can sting hard.

    The same logic applies if you’re planning to exercise the optional final payment and keep the car. That’s your decision and your car from that point forward, so nobody cares what you do after. The risk window is specifically the period before you own it outright.

    Voluntary termination and how a remap complicates it

    Under Section 99 of the Consumer Credit Act, you have the right to voluntarily terminate a regulated HP or PCP agreement once you’ve paid 50% of the total amount payable. This is one of the most useful and least-advertised consumer rights in UK motoring. Lenders don’t broadcast it for obvious reasons.

    The catch is condition. When you hand the car back under VT, it still needs to meet fair wear and tear standards. A remap flagged during the post-return inspection is a modification the lender didn’t consent to, which gives them grounds to pursue a damage claim against you even after the VT. If the ECU has to be reflashed at main dealer rates, you’ll be paying for it. Some lenders include specific language around “unauthorised modifications” as a ground to dispute a clean VT, so check your agreement before you remap and before you invoke Section 99.

    If you’re considering a VT, it’s worth reading up on the hidden costs of running a modified car first, because the financial picture changes considerably once you factor in what you might owe on the way out of a finance deal.

    Company car users and HMRC mileage rules

    This is a corner case, but it affects more people than you’d think. If you run a company car on a PCP arrangement through your employer or via a salary sacrifice scheme, remapping creates a tax complication on top of the contractual one.

    HMRC’s Approved Mileage Allowance Payment (AMAP) rates are based on the car’s original engine specification. If you’ve remapped the car and increased its power output, HMRC’s position is that the vehicle’s characteristics have changed. In the context of a Benefit-in-Kind (BIK) calculation, any change to the car that materially affects its CO2 output or performance spec should technically be declared. A stage one remap can alter real-world fuel consumption and CO2 figures, even if the official type-approval figure doesn’t change. HMRC’s guidance on company car benefits is set out on gov.uk, and while it doesn’t call out remaps by name, the principle of using official figures is clear. If you’re caught between a mapped car and a salary sacrifice agreement, speak to a tax adviser before anything else.

    How specialist insurers view a remapped financed car

    Standard comprehensive insurance covers the car in its factory specification. Declare a remap to a mainstream insurer and your premium goes up, or they decline cover. Don’t declare it and you’ve invalidated your policy. That’s the binary choice with mainstream cover, and most people already know this bit.

    What’s less well understood is how specialist modified car insurers handle the finance angle. Companies like Adrian Flux or Reis Motorsport Insurance will cover remapped cars, but their proposal forms ask about finance agreements because it affects who has an insurable interest in the vehicle. If you’ve remapped without lender consent, some specialist insurers will flag that as a potential issue with the underlying contract and factor it into their underwriting. It doesn’t necessarily mean they won’t cover you, but you need to be straight with them from the start.

    The insurer angle also matters because, if the car is written off and the lender discovers the remap voided your original comprehensive policy, the GAP insurance product sitting alongside your PCP could also be affected. GAP pays the difference between the insurer’s payout and your outstanding finance balance. If the underlying insurance claim is disputed due to an undisclosed modification, the GAP claim goes with it. That’s a scenario worth avoiding.

    I’d always recommend telling your insurer before you do anything to the car. I’ve seen blokes assume the remap is undetectable and then find themselves uninsured after a bump. It’s a grim situation. For a broader look at how modifications affect your cover, the piece on what happens to your car insurance if you modify your engine covers the mechanics of it well.

    What you can actually do to protect yourself

    The cleanest route is to ask your lender in writing before you remap. Most won’t say yes, but getting a refusal in writing at least documents that you made the attempt. Some lenders, particularly those financing performance cars, are more relaxed about this than you’d expect, especially if the modification is reversible.

    A reversible remap, where the tuner retains the original file and can restore factory calibration on request, is the most sensible approach if you’re determined to tune a financed car. It doesn’t make the modification contractually permissible, but it dramatically reduces the practical consequences at handover. Keep the original file backed up and be ready to restore it before any dealer inspection.

    If you’re close to the end of the agreement and planning to make the final payment, just wait. The whole problem disappears the moment legal ownership transfers to you. For anyone thinking about a performance purchase outright rather than on finance, the guide to buying a performance car from a private seller is worth reading alongside this one, because ownership clarity matters at every stage of the process.

    Remapping is a legitimate and effective way to get more from a modern engine. The science is sound, the gains are real, and for the right car the transformation can be significant. Just make sure you’re not gambling your finance agreement, your insurance, or your voluntary termination rights for the sake of an extra 30bhp you could have legally enjoyed in six months’ time.

    Frequently Asked Questions

    Can I remap a car that's on PCP finance in the UK?

    Technically you can, but most PCP agreements prohibit modifications without the lender’s written consent, since the finance company retains legal ownership until the final payment. Doing it without permission risks breaching your agreement and could lead to charges at handover.

    Will a remap be detected when I hand a financed car back?

    Possibly, yes. Modern cars store ECU logs that dealer diagnostic tools can read. Manufacturers like BMW, Ford and Volkswagen all have systems that can flag third-party calibration events. A visual inspection won’t catch it, but a proper scan often will.

    Does remapping affect my voluntary termination rights under PCP?

    Your right to voluntarily terminate under Section 99 of the Consumer Credit Act remains, but the lender can still pursue costs if the car isn’t returned in acceptable condition. An unauthorised remap can be used to justify a charge for ECU restoration, even after a VT.

    How does a remap affect company car tax and HMRC rules?

    HMRC calculates Benefit-in-Kind tax using the car’s official CO2 figures. A remap can alter real-world emissions and performance characteristics, which may create a discrepancy worth declaring. It’s advisable to speak to a tax adviser if you’re in a salary sacrifice or company car scheme.

    Which insurers will cover a remapped car on finance in the UK?

    Specialist insurers such as Adrian Flux and Reis Motorsport Insurance will cover remapped cars, but they need full disclosure including any finance arrangement. Failing to declare a remap to any insurer, specialist or otherwise, risks invalidating your policy and any associated GAP cover.