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HARRYS EURO - NZ's Largest Online Performance Parts Store
HARRYS EURO – NZ's Largest Online Performance Parts Store
UNITRONIC AUDI RS4 2.9TFSI EA839 TCU PERFORMANCE SOFTWARE - Harrys Euro

UNITRONIC AUDI RS4 2.9TFSI EA839 TCU PERFORMANCE SOFTWARE

by UNITRONIC
Sale
$109.65
$92.99
Features
  • Unitronic Engineers identified gearbox originating torque limitations on the TCU side of the AL552 transmission. In order to overcome these limitations, while ensuring proper torque management and operation, a TCU Performance Software was required to run Unitronic Stage 1, 1+ and Stage 1+ E85 ECU Performance Software for the B9 RS 4 & RS 5.

    Stage 1 TCU Performance Software calibrations necessarily increase the torque limiter for seamless torque management and harmonious operation with the corresponding Unitronic ECU calibrations and further enhance the user experience.

    For MY2022+ vehicles, TCU tuning is not required as Unitronic has developed special ECU Performance Software which incorporates a proprietary "gBX" solution. These "gBX" ECU calibrations were developed specifically for MY2022+ vehicles and allow Unitronic to deliver a full torque experience without transmission tuning.
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  • NZ's largest Online performance parts store
  • All products backed by manufacturer warranty
  • 100% genuine parts
  • Hassle-free 30-day returns & refunds
  • Competitive pricing
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  • Workshop installation available
  • Fast 1-3 days dispatch on in-stock items
  • Shipping from only $11.90
  • Click & collect available
  • Dealer-level MTA workshop
  • Expert tuning, upgrades, and servicing
  • Visit us: 15a parkway drive, Rosedale, Auckland
  • Open 6 days

Harrys Euro

150+ Brands · 30,000+ Performance Parts

Proudly Serving Kiwi Drivers for Over 9 Years
Store & Workshop
Workshop

Parts + services, under one roof

Shop performance parts in-store or online, then have them fitted and tuned by the same team. No referrals, no second trips.

Performance

Dealer-level workshop, MTA assured

Fully equipped to support late-model European vehicles — diagnostics, servicing, and performance builds done right.

Parts

Built for real-world performance

We fine-tune high-performance machines to suit how you actually drive.

Happy Customers

4.8
Based on 146 Google reviews
as of 01/05/2026
Shanijah Taylor
Shanijah Taylor
Just wanted to share some love to Harry's euro and their team! Bought parts for my r32 and gti, they never disappoint. Love being part of the euro community in an ever so dominant jdm culture in New Zealand. Looking forward to bringing an rs3 in for tuning :)
Greg Davies
Greg Davies
Great to have parts for my Range Rover so readily available in nz. Fast delivery and awesome quality products. Thanks guys!
Nick Ko
Nick Ko
I took my BMW to get the downpipe installed. Harry's Euro has done an excellent job. I'm very satisfied with the quality of their work. The staffs are very nice. Highly recommended. 10/10
Sebastian Ramirez
Sebastian Ramirez
I've been a loyal customer of Harry's Euro since 2017, and I can confidently say Scott and his team are the best in the game. Not only do they consistently offer the best prices, but the service is always top-notch. Scott is honest, transparent, and always takes the time to explain what’s going on with my car. Whether it's routine maintenance, unexpected repairs, or upgrades, I always know my car is in the best hands. Highly recommend to anyone looking for a reliable, expert mechanic!
Andrew Atkinson
Andrew Atkinson
Used Harry's Euro for years owning a Mk6R and now a Mk5 R32. Amazing service and delivery! R32 kit arrived today with some extra goodies! Pleasure to deal with the team!
Mark Barber
Mark Barber
Hands down the best Euro shop in Auckland. They've looked after 2 builds of mine, and the parts, service and expertise has been top notch.
Marc Graham
Marc Graham
Harry's Euros delivered platinum service from start to finish. The quality of the products is excellent, and the install experience was smooth and professional. If you want a lower cost acceleration boost ask Scott about a Pedal Box! Huge difference and very simple to use.
Quinn Ashby
Quinn Ashby
Got some basic servicing and a Stage 2 transmission tune done today to match the ECU tune. The team was really helpful with information, communication via email, fit me in quickly, and offered fair, industry standard pricing for a specialised shop. Highly recommend, and I'll definitely be back!
Hayden Lawrence
Hayden Lawrence
Great service. Needed a replacement driver's side mirror glass for our old GTI. Harry's Euro had it in stock for a good price and shipped it next day. Very pleased with the transaction and will happily recommend and use them again.
SladeDaSlide
SladeDaSlide
Been Working with Harry's Euro for almost 3 years now and I can highly recommend any auto-work or performance upgrades to be done by these guys. I've had my previous car and my current done by the team cheers to Scott and the boys for the work 🍻
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Press & Media

Harrys Euro in the Media.

New Zealand's automotive publications have documented our work and expertise.

Euro Tuning Explained – Project R Part 3
NZPC · Project Series 31 December 2025

Euro Tuning Explained: How It Really Works — Project R, Part 3

In part 3 of a featured Golf R build series, NZ Performance Car visited the Harrys Euro workshop to explore the realities of Euro tuning. The article highlights our team's expertise, detailing the installation and custom ECU/TCU calibration of the Harrys Euro Stage 2 EA888.3 400 Package.

Read Full Article on NZPC ↗

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