Welcome to the next development car here at Carbonwurks, The Mini Cooper F66 JCW! It’s been a long three months waiting but it was a plan that was concepted by us last year when Mini announced and released the new JCW. Those in the know will know that back in 2023 we purchased the Mini Cooper JCW F56 JCW LCI2 with the intention of showcasing what we can do ourselves in terms of performance upgrades to these cars as well as developing new parts for it. Little did we know back then how popular this process (and YouTube series) was going to be. We complemented it with a blog post which also performed great!

In the year that the F66 JCW has been around, the upgrades and performance parts that have been released have been done very slowly and nobody is showcasing what an awesome car this is. We decided to in a sense, to repeat history with the newer 4th generation JCW. It took us a good few works to work on the ideal spec of car that we wanted and plan it’s future in terms of the upgrades available as well as making plans with some big brands out there to get our car to them for R&D / development work.

Like before we’re going to film and document the whole process over on Youtube as well as here on this blog in a more written format! We’ll showcase the exact modifications and upgrades we’ve done, link to the relevant products on our website as well as giving you a brief write-up why and what it’s achieved. This will for want of a better phrase be a live / running blog that we’ll be updating as we go along. We’ll drop each video here on this blog as well so it’s all in one easy place to access!

To start, we picked up the F66 JCW in December 2025 from Marshall Mini right here in Bournemouth. The team there were great, they saw the vision and couldn’t have been happier to help us out. As it was the start, we had to film the collection below.

Part 1 – The Engine Bay

The first thing we had to sort out was the engine bay as from factory it’s a bit boring and a bit dull. We’re also awaiting the first wave of parts for the bigger more exciting elements to upgrade on this F66 JCW to make it a true JCW in terms of looks and sound! We wanted to do this part a bit differently and give it the supercar engine bay that it deserved to have from factory.

We decided that it was important to not only make the engine bay look as good as we could but also help with some of the front end noise. We all know that thanks to the new EURO 7 emissions this car sounds very quiet and we thought we can quite easily change this. The first part of the upgrade was the Armaspeed Carbon Fibre Intake which not only greats it really improves that front end noise and “whoosh” noise that we all know and love. We paired this up with our own Carbon Fibre Engine Cover which we treated to a nice subtle grey JCW emblem to bring that styling into the engine bay.

To finish this area off we installed a RAW Titanium Engine Bay Kit from our friends over in the US, Downstar Inc. The end result was not only a more visually impressive engine area when you lift the bonnet but one that sounds better and helps the car breath a little bit better.

We have more things in the pipeline for the engine bay (One that we’re really excited about) that will feature in an upcoming video but in the meantime, take a watch of this full upgrade on the video below:

Part 2 – Improving The Front End Sound

Having sat with the Armaspeed intake for a month or so (Which is a great sounding option and looks great) we decided it was time for a change-up and to see if we could get any further sound from the F66 JCW! This timed in nicely with the guys from Forge Motorsports who sent us a big box of goodies in the form of an e-DV (Electronic Diverter Valve) or for those who commonly know it as a dump or blow-off valve! They also sent us their carbon fibre intake and inlet / intake silicon “hard” pipe (Which is actually fairly flexible) which will feature in a separate video later on down the line.

In the most recent offering on YouTube we’ve installed and tested the e-DV and we’re pretty impressed. Not only British Engineering at it’s finest it’s plug and play that replaces the restricted factory version. It not only improves the sound of the vehicle but actually has helped with improving the throttle response of the car.

Take a watch of how we get on and how it sounds once installed:

Part 3 – Time For Some Security

As we continue the build of the Mini F66 JCW it’s also important to start upgrading it’s security when you’re investing so much into it. Whilst the level 3 Mini F65 / F66 / F67 have the on-board drive recorders (Like BMW) our car is a level 2 so it didn’t have this feature built into it. It’s also arguably not as good as what a dashcam can offer in terms of recording quality and the fact it will work when parked up.

The guys at Sytner Mini who we deal with quite a lot, told us about the all new Mini Advanced Car Eye 3.1 which has a boat load of upgrades over it’s predecessor the 3.0. As we were looking into this options it was a no-brainer to get one bought and installed into the Mini. It keeps everything on brand and looks like it was there from factory which is great!

A few years back we did the same with the BMW variant for our M4 G82 and it racked up quite a few views (Nearly 200k in 2 years) so it was well worth doing it again for the Mini dashcam.

If you want to have a look at some of the footage as well as our thoughts, you can check it out on the video below:

Part 4 – Making It Sound Like A True JCW

Whilst overall we were quite happy with how the car was sounding it still wasn’t ticking the box for us when it came to the sound department and more could be done. We really like the way the Armaspeed looks and sounds but when the guys at Forge Motorsport told us their version of a carbon fibre intake was ready along with their silicone “hard-pipe” intake pipe was ready we decided to switch things up a bit.

Once all installed not only did it look great but it really finished off the true JCW sound we were looking for from the front end. A very pleasing intake sound when mixed with the e-DV it really starts turning heads!

Take a watch of how we get on and how it sounds once installed:

Part 5 – Now It Looks Like A JCW Thanks To AC Schnitzer

This one has been a few months in the making as we were on the first in the UK to get a full AC Schnitzer kit on order for our F66 JCW. Whilst we didn’t “hate” the JCW Pro Pack it didn’t really fit the vibe of what we were looking to do with the Mini and we wanted more aggression.

Our Mini was treated to the FULL AC Schnitzer upgrade conversion which included all the Aero Pack (Front Splitter, Front Canards, Side Skirts, Rear Spoiler), Twin Exhaust System, Front & Side Decals / Vinyls as well as few trick bits inside.

All in, this has transformed the car into how it should of looked from factory. Full JCW aggression!

Take a watch of the full build along with the final looks and sounds:

Part 6 – Time To Improve The Cooling

With the majority of the styling done with the F66 after the AC Schnitzer build it’s time to start looking at the power aspect but before we do that we want to ensure the car itself is ready for the extra performance. With the tuning / remap / calibration very slim here in the UK we’ll be going down the route of the AC Schnitzer tuning box at some stage. Whilst the gains are modest and we don’t “need” to improve the cooling it’s always worth doing. Our friends over at Forge Motorsport of course were only too happy to help!

They took the car off for some development work and testing and came back to us with an incredible upgrade that will help the car when tuning and for those vehicles in different countries where the ambient temp is much higher and an intercooler will certainly help!

Not only was the installation an absolute breeze (One of the easiest we’ve ever installed) but it performs very well! With an overal 72″ increase in cooling area and 40% volumetric it lowers the intake air temps and offers a much more stable delivery of power!

Take a watch of the installation as well as our thoughts on the video below:

Part 7 – Making The Steering Wheel The JCW Deserves!

Whilst many of the F66 haters out there don’t like the interior on this new vehicle (when compared to the F56) we actually love it but we felt it could of done with one thing that was much better, the steering wheel. The original is “ok” but unlike it’s big brothers in the BMW world there was no option for a better performance / sport version as seen on the M-Powered cars. The paddles were lackluster and you didn’t feel that connected to the car when driving it.

Enter the chat, the CW Alcantara / Carbon Fibre Steering wheel with Carbon Fibre Magnetic Paddles! Being a carbon fibre company we had to bring some into the inside of the car and we’re all massive fans of Alcantara so it was a natural choice. To pay homage to the original Mini JCW F66 wheel we kept the same lower strap at the bottom of the wheel but also included one our “Track-Pack Race LEDs with shifters”. This means we can pull live data from the OBD and display it on the wheel which will be very handy whilst on track!

The great thing about this wheel is that it’s customisable so if you yourself want an upgraded steering wheel, there’s lots of different options you can choose from in terms of the materials, the colours, the tech etc etc.

See how the steering wheel looks (and hopefully) feels like on the video below:

Part 8 – Bringing Back The Twin Exhaust To The Mini Cooper F66 JCW

The marmite aspect of the Mini Cooper F66 JCW is the single exhaust at the back of the car. Whilst it pays homage to the old school Mini Cooper Rallye cars it’s certainly a marmite feature that some people love and some people hate. We actually quite like the single pipe exit and it does make it different to every car out there but we still had the pull to get a twin exhaust back on the car.

We decided to film a standalone video to showcase it in all it’s glory and it was received very well (More views on YouTube than the main overall AC Schnitzer build). This particular system is for the Cooper S but we made it work with the JCW (Doing away with the valving) and it worked great with no issues or errors on the car.

Featuring a Twin exit exhaust with a replacement centre panel for the diffuser it looks like it was always there on the car. Now the car has done a few miles with it installed, it really does sound rather good and how it should of sounded from factory!

Take a watch of the full build and see what it sounds like yourself:

Part 9 – Yet Another Intake Video?!

Whilst we were certainly happy with the Forge Motorsport intake and it’s associated upgrades that we did over in part 4 we were waiting for the King of the intakes to enter the chat from the guys over at Eventuri. We reached out to Imran in the early stages asking for a system for our car that we could test and trial out and he was only too happy to oblige!

This system fitted just like an OEM would, there was no modification required. It just went in and worked and by George does it look good next to our carbon engine cover and Downstar Inc Engine Bay bolts!

So blown away by it’s sound (and looks) we’ve decided to keep it in play on the car! See it in all it’s glory on the video below:

Part 10 – Bringing Back The Big Brakes!

As we look to increase the power on our F66 JCW it was time to turn our attention to braking. Those in the know will know that for this generation Mini went for a smaller calliper at the front than on previous generations (Cost-cutting exercise most likely) and went from 4-pot to single pot. Whilst day-to-day usage of these cars they will be more than sufficient they look quite small and when pushing the car hard they are underwhelming.

After a few trips to and from EBC with our car we had them develop a kit for the F66 JCW and Cooper S to bring back some serious stopping power and the all important bigger calipers, upgraded discs, pads and braided brake lines!

Watch how we developed this kit from inception to getting them installed:

If after reading and watching about what we’re doing with this Mini then you can find all the current products and upgrades available here in our general Mini Cooper S / JCW F66 Upgrades Blog or view all the products in our specific Mini Cooper F66 Collection on the main website.

You can also follow our current progress on our Mini Upgrades over on Instagram and Facebook:

Instagram – @MiniCooperF66

Facebook – Mini F65 / F66 / F67 – 4th Gen Forum