Performance Engine Upgrades Specialists in Slough

Performance Engine Upgrades Specialists

Unlock the full potential of your vehicle with our expert performance engine upgrades in Slough. We specialise in precision tuning, high-performance component fitting, and bespoke modifications designed to deliver more power, sharper throttle response, and improved efficiency.

From ECU remapping and turbo upgrades to high-flow intake systems, exhaust upgrades, and performance camshafts, every upgrade is tailored to your driving style and performance goals. Whether you own a sports car, luxury vehicle, or modified project car, we use only trusted brands and proven techniques to achieve exceptional results.

Our Slough-based workshop attracts car enthusiasts from across the UK thanks to our attention to detail, advanced diagnostic equipment, and passion for performance engineering. Every job is carried out by skilled technicians who ensure reliability matches the performance gains.

Tuning Gain Calculator

Why Choose Onyx Performance?

As Seen on Carwow

We’ve been proudly featured on Carwow – a testament to the quality, professionalism, and performance-focused results that set us apart. Watch our feature here to see us in action.

Expertise You Can Trust

With years of experience and deep technical knowledge, our team understands performance vehicles inside and out – from custom remaps to high-end servicing.

Advanced Workshop & Tools

We operate from a state-of-the-art facility in Slough, equipped with cutting-edge diagnostics, dyno testing, and industry-leading tools for accurate, high-quality work.

Tailored Solutions for Every Vehicle

We don’t believe in one-size-fits-all. Every car gets a bespoke approach, ensuring the best results whether it’s a remap, upgrade, or routine service.

Trusted Nationwide

Performance enthusiasts from across the UK come to Onyx because they know they’ll receive premium-quality workmanship, careful attention to detail, and honest advice.

Complete Care, All in One Place

From tuning and servicing to tyres, trackers, and immobilisers – we offer a full suite of services under one roof, all with a strong focus on safety, reliability, and top-tier customer support.

Customer Reviews

    
 
 
       Posted on Google  
   
   Anil Soni 
 
 
 
 Trustindex verifies that the original source of the review is Google. Thank you guys for your professional, dedicated and honest opinion. You made my day by fixing my son's car so he could use it for DoE at very short notice. Max and Kay were brilliant and I would definitely recommend this garage as a organised and trustworthy business. Keep up the good work.
  
 
      Posted on Google  
   
   subin pradhan 
 
 
 
 Trustindex verifies that the original source of the review is Google. Took my BMW 440i to install downpipe and mid pipe. Top guys with good service and reasonable price. Will be going back for more work done.
  
 
      Posted on Google  
   
   J JareCki 
 
 
 
 Trustindex verifies that the original source of the review is Google. I just done Stage1 in my audi s3, car drive superb, excelent service, thanks Ben,Sam and Onyx team! Brilliant work
  
 
      Posted on Google  
   
   Dan May 
 
 
 
 Trustindex verifies that the original source of the review is Google. Honest and knowledgable! Rare these days - saves me hundreds by checking my Golf R properly. Will only use these guys from now on
  
 
      Posted on Google  
   
   Darren Dawes 
 
 
 
 Trustindex verifies that the original source of the review is Google. I took my jaguar xfr to these guys for a re map . Excellent service. They could not have been more helpful. Very knowledgeable they definitely know what they are doing. If your looking for a re map I would highly recommend you speak to them.
  
 
      Posted on Google  
   
   Hana 
 
 
 
 Trustindex verifies that the original source of the review is Google. I was recommended Onyx to get my diamond-cut alloys refurbished. I am located an hour away but the recommendation was important so decided to leave my car with these guys. First impressions, the team were very polite, friendly (Essan, Ben and the guys that actually did the refurb in the intense heat) The prices were competitive. And the quality of work was super. There was slight miscommunication post the sale (which happens) but I was pleased they resolved this to my satisfaction. One idea I would suggest is advising the customer 'before' the work starts that the TPF valves may need replacing so we have the option to decide whether to do it whilst the wheels are off anyway rather than post refurb to avoid scratching the newly done alloys. Otherwise happy with my overall experience.
  
 
      Posted on Google  
   
   Mark 
 
 
 
 Trustindex verifies that the original source of the review is Google. Amazing service
  
 
      Posted on Google  
   
   pavan khangura 
 
 
 
 Trustindex verifies that the original source of the review is Google. The best experience ever well organised clean friendly team and the experience was amazing A big up to the whole staff.

Book Your Performance Engine Upgrade in Slough

Transform your driving experience with professional performance engine upgrades at our Slough workshop. We offer custom ECU tuning, turbo and supercharger upgrades, high-performance exhausts, and precision component fitting to deliver the power and responsiveness your car deserves. Contact us today to discuss your performance goals.

5-Star Google Reviews

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Why Choose Onyx Performance for Servicing?

Experts in Performance Cars

We know how to properly care for performance, modified, and luxury vehicles. Our team has the skills and experience to handle specialist requirements confidently.

Correct Service Schedules

Every service follows the exact schedule recommended by your vehicle’s manufacturer, helping maintain performance and protect your warranty.

Quality or OEM Parts

We only use high-quality aftermarket or original manufacturer parts, ensuring long-lasting reliability and top-level performance.

Full Vehicle Inspection

Our service goes beyond just changing oil. We inspect all key systems to keep your car safe, smooth, and road-ready.

Honest Advice, No Surprises

With transparent pricing and expert recommendations, you’ll always know what your car needs – no upselling, no hidden fees.

Fast, Trusted & Tracked

We offer quick turnaround, maintain service records, and send reminders – that’s why customers travel to us from across the UK.

Frequently Asked Questions

What types of performance upgrades do you offer?

We provide ECU remapping, forced induction upgrades, intake and exhaust modifications, and high-performance engine components.

Will my engine remain reliable after upgrades?

Yes – all upgrades are designed and installed with engine longevity and safety in mind, using quality parts and professional fitting.

Do you work on both petrol and diesel engines?

Absolutely – we have extensive experience upgrading petrol, diesel, and hybrid performance engines.

Can you upgrade my car for track use?

Yes – we can install track-focused upgrades such as race-spec turbos, cooling enhancements, and performance mapping.

Will performance upgrades affect my fuel economy?

It depends on your driving – increased power can be driven economically, but spirited driving will naturally use more fuel.

Do you offer custom tuning for modified cars?

Yes – we create bespoke tuning maps to match your specific modifications for maximum performance gains.

Get a quick quote

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