Chiptuning-info

Key takeaways BHP is measured at the flywheel, WHP at the wheels, so wheel figures are always lower. Comparing a wheel figure with a manufacturer's BHP figure is misleading without allowing for drivetrain loss. Different dynos and calculations give different numbers, so only compare before and after runs on the same machine. Ask for the full graph, not just the peak number. A dyno graph is the most common proof a tuner shows to sell a remap. It can be useful evidence, but only if you know what you are looking at. This guide explains the main terms and the traps to watch for, with help from two UK motoring sources. BHP and WHP: what is the difference? As explained by Car Throttle , brake horsepower (BHP) is measured at the flywheel and reflects the power delivered to the gearbox, while wheel horsepower (WHP) is measured at the wheels. WHP is always lower because it includes the losses through the gearbox, driveshafts and the rest of the drivetrain. Car makers usually quote BHP becau...

Key takeaways Tell your insurer about a remap before you tune, not after. Which? lists ECU modifications among the engine changes insurers expect to hear about, and staying quiet could invalidate your policy. Your premium might rise, or it might not. Performance changes tend to cost the most. Specialist insurers, independent brokers and owners' clubs can help if mainstream quotes are poor. Many owners focus on what a remap does to the car and forget to ask what it does to the insurance. In the UK that can be an expensive mistake. This guide explains what to declare, what can happen if you do not, and how to find sensible cover, using advice from the consumer organisation Which?. Why you must tell your insurer The Which? guide to modified car insurance says you should tell your insurer about any modification, and that insurers can class more things as modifications than you might expect. It lists engine and mechanical changes, including ECU modifications, among them. A remap change...

Key takeaways A remap is not illegal in itself, but removing or disabling emissions equipment is a different matter. On a diesel built with a particulate filter, a missing DPF fails the MOT, and GOV.UK says removing one is almost always illegal. The official DVSA guide on modifying emissions has been withdrawn for review, so always check current rules. A reputable tuner leaves every emissions system in place and working. People often ask whether chiptuning is legal in the UK. Changing engine software is not the problem. What matters is what the changes do to your car's emissions equipment. This guide uses official GOV.UK sources to explain where the line sits, so you can judge what a tuner is really offering you. What the MOT checks Since February 2014, the MOT exhaust inspection on diesel cars has included a check for the diesel particulate filter, or DPF. According to the government announcement of that change , a car that was fitted with a DPF as standard fails if the filter has...