Onyx Performance - Rolling Road Tuning, Dyno Runs, Car Service Centre & Alloy Diamond Cut Refurbishment

When I wanted a Scorpion exhaust fitted to my BMW 128ti the guys at Onyx couldn't have made the process any simpler. To begin with, we were on a tight timescale to place the order as it was a Bank Holiday weekend and Scorpion were offering special pricing. My email was picked up on a Sunday afternoon, and followed very quickly by a phone call. I soon had the order placed and the car booked in. Nothing was too much trouble and I'd highly recommend!

I bought already performance parts (manifold, downpipe and decat) for my Toyota and needed someone genuine and reliable to install them since my car is very old and can be tricky to deal with it's parts, Onyx was the best place to visit and get the job done for me, the team was very welcoming, explained to me the process from A to Z, job was done in a very effecient time line, really happy with there service, recommended

Not sure where I even begin, firstly they answer the phone when you call which is always important. I explained my issues and though my car is heavily modified not by them they were honest as whether they thought they could help with diagnosing the issue with my car. The garage is clean and professional. Most importantly the service was A1, I dealt with SN who was being as helpful as possible though their equipment may had not worked with my modifications. After a few changes to my car the equipment would fit nicely and allowed them to carry out the test.I would not hesitate taking my car back to Onyx Performance should I need to. Also bring 7 minutes from my home they are now the most local garage I’d considered that could help me in the future with my cars modified or not

The guys over at ONYX Slough were top tier. They definitely know their stuff, amazing customer service and reliability from start to finish. This is my 2nd time using them for my M140i and definitely wouldn't go anywhere else.100% recommended for every service.

Had my Range Rover rear privacy tints re-done from these guys because when I bought the car the tints were fading, cracking and had creases. These guys went above and beyond and delivered the best quality film, tinted my lights and even offered lifetime warranty. Excellent quality finish. Highly recommended, fantastic service.

I cannot recommended Onyx Performance enough for their services. Booked my car in for some stage 2 work and not only was it fast and professional but they carried out everything I asked for and delivered back to me a beast of a car, for which I am very grateful for! SN you absolutely smashed it, keep doing what you’re doing bro and I will back again soon for sure.

I came to Onyx for an Alloy refurb on my Leon Cupra. They did an amazing job, and gave great customer service. I've recommend them to friends and can confidently say they're the best in Slough!

Had my Abarth remapped here, drives faultlessly & feels must more powerful. Also seems a lot better on fuel too, bonus!! Great staff & wide range of advice to get the best results. Very happy customer.

took my 116i for a stage 1 remap. staff are very friendly and told me everything i needed to know. easy booking process and lots of services to offer other than remapping. Will definitely come back again.