Performance Upgrades

Want to increase the drivability and performance of your vehicle? If you’re looking for your vehicle to be more agile, faster, feel more powerful and generally kick it up a notch; you should consider the benefits of car performance upgrades.

With our years of experience in the industry, we can accelerate your vehicle into overdrive! We specialise in modifying, calibrating, and supplying high-performance diesel and petrol injection components that are designed to meet the varied demands of the racing & performance markets. When it comes to investing in a car performance upgrade, it’s important that you do your research. You need to ensure firstly what you want to get out of your upgrade, what the possibilities are with your vehicle and find a provider who has the experience and knowledge to give you the power you’re after!

Car Performance Upgrades | United

Accelerating Your Vehicle’s Performance

At United, we provide completely bespoke injectors and fuel pumps, combined with the correct engine build and tuning, to enhance performance and racing vehicles. Experience an improved drivability, that perfect drive and feel the power rush!

If you’re unsure exactly what kind of upgrade you need, our team of experienced engineers can help. Whether this is just to enhance the power of the vehicle, boost the performance for racing or you have a different vision in mind; we’ll get under the hood to analyse the current engine and mechanics and see what exciting improvements we can make!

Did you know the quickest 1.9TDI MK4 Golf in Europe has been tuned to achieve 449 BHP with Nitrous 590 BHP? This is a long way off the factory specification of 130 BHP!

This service offers you…

  • Upgrades to diesel injectors using high-flow nozzles and specialist calibration technics.
  • Calibration of the injectors to ensure the flow characteristics of each high-performance diesel injector are balanced to obtain the best possible performance.
  • A selection of up-rated performance injectors and pumps for various diesel engines. Some are a quick and easy fit to enjoy an increase in power and torque. Others are for the more dedicated owner and tuner that require more sophisticated engine modifications.
  • A selection of ASNU Performance petrol injectors are designed bespoke and built with the ideal spray pattern to match the required flow.
  • Fuel delivery and mapping charts are available on request for specific modifications.

Proven Performance

We’ve worked with clients to help them see performance in their vehicle like never before. See below a small case study of some car performance upgrade engineering we completed with one of our clients for their Volkswagen Golf 25th anniversary 1.9tdi PD150.


Engine modifications included:

  • 1.9tdi engine
  • Turbo – BMW GTD 3071 ball bearing
  • Diesel injectors – 120% firads (supplied by us!)
  • Dbilas 272 9.8mm lift camshaft
  • Uprated valve springs and retainers
  • Ported & gas flowed cylinder head
  • 42mm piston bowls
  • Uprated forged rods
  • 3-inch boost pipes
  • Sachs 4 paddle dmf clutch kit
  • 3-inch bonnet exit exhaust
  • 6 bar map sensor
  • 4-inch intake
  • 2 stage nitrous
Performance Upgrade Service | United

Gearbox modifications included:

  • Quaiffe LSD
  • Steel forks
  • 4th gear support
  • Gearbox strengthen plate


Following car performance upgrades and modifications, the vehicle saw a massive uplift in speed and efficiency, including a best ¼ mile time of 10.85 a 136mph, a best draggy time of 0 to 60 miles in 3.4 seconds and 100kmh-200kmh speed reached in just 6.4 seconds.

Want to know more?

For more information on our services, expertise and how we can support you, download our brochure. Got a specific question? Get in touch with the team today.

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