Developing the NEW Toyota GR Yaris

One of the most talked about hot hatches of the last 2 years, the eagerly awaited Toyota GR Yaris is now reaching customers. Building on the excitement of the GRMN Limited Edition from a couple of years ago, the new GR Yaris has firmly planted itself as a force to be reckoned with glowing reviews from all corners.

It wasn’t long before we took delivery of our Black Circuit Pack GR Demo car and started to put it through its paces with our very own tame racing driver Josh Cook at the wheel. When not behind the wheel of the BTC Racing Honda Civic FK8 in the British Touring Car Championship (BTCC) he can be found here in Radstock at Cooksport HQ getting hands on with the technical developments and product testing. After lapping Donington Park Circuit and regular road driving it was noted improvements could be made.

Which are the best aftermarket wheels for the GR Yaris?

Firstly, we wanted to improve the look of the car, for many the first change to personalise a car are the wheels. While the BBS wheels as standard on the Circuit pack cars are light weight forged items, they aren’t the prettiest wheels and look somewhat lost in the broad arches. The non-circuit cars too will see many changing out the stock wheels. We called on our partners at Speedline Corse to supply us with some extra width, selecting the Turini 2120 wheel we are very familiar with, being hugely popular in the Renault Tuning scene we largely cater for.

We had some custom made exclusive to Cooksport 18×9 et55 in white in stock ready for the track mated to Pirelli P-Zero Trofeo R and 18×8.5 et45 in silver for the road with Goodyear winter tyres for the poor winter conditions at the time.

What are the best Braided Brake Lines for the GR Yaris?

With the wheels upgraded we set about making braided brake lines for the car. As many of these cars will be hitting the track, we wanted to ensure that customers could upgrade fluid and lines for reliable pedal feel from the start to the end of the day, every day.

Cooksport are an approved HEL Performance manufacturer and offer a lifetime warranty on all brake lines.

A set of 4 braided brake lines is now available from Cooksport for £75 inc. VAT.

Coilovers for a GR Yaris

Next up was the development of the AST Suspension system. Being the sole UK distributor of AST and Moton Suspension, we are perfectly placed to ensure that the fitment, ride quality and performance are on point. In production now, we will have solutions for the enthusiast on the road, plus circuit focused options with alternate spring rates and valving to suit customer requirements.

Once the AST Suspension kits hit the ground here at Cooksport HQ we will be able to put our geometry expertise to good use. Changing the suspension is just the start to making the car come alive. Even some of the best handling cars are held back from ultimate performance, instead aiming the geo setup at tyre wear, and easy to control understeer for novice drivers. We can tune the geo for customer requirements but for us, certainly some more rear bias is certainly in order, getting that 4wd working for us and unlocking that hidden performance.

How to reduce engine movement in a GR Yaris?

Turning our attention to the gearbox, as we noted it needed some improvement. Under heavy acceleration we were encountering engine movement. For the track focused cars, we designed a lower engine mount. Taking the movement of the engine away made for a guaranteed shift. Engine mounts are often one of the control parts added to production saloon cars like Clio Cup where the focus moves away from ultimate comfort to all out-track performance.Designed and manufactured from billet aluminium again by us at Cooksport we ensure light, strong quality parts.

Which is the best aftermarket exhaust for the GR Yaris?

Another widely echoed comment about the car is that the peppy 3-cylinder engine leaves a lot to be desired aurally. Somewhat strangled, the exhaust really needs to be swapped out to give the car the sound that backs up the performance. We set about developing a range of Cooksport 3” stainless steel exhaust systems to match customer requirements, cat back and back box, in both resonated and non-resonated options with carbon tail pipes. Get in touch now to grab yours. Our preference is the non-resonated mid pipe with the silenced back box. It’s a great improvement to the sound of the car outside, but also inside, something for the enthusiastic driver to enjoy, with the added gains of performance improvements that a large diameter exhaust can give.

Prices start from £650 inc. VAT. Available exclusively at Cooksport.

Tuning and Re-mapping a GR Yaris

Performance improvements on the model coming from breathing modifications like exhaust and induction are popular along with remapping. The GR Yaris is no exemption, as such we have the 3” GPF replacement front pipe to match the Cooksport cat back exhaust, for those customers looking to change ECU, remap or piggyback tune their Yaris.

Power figures for the exhaust systems will be published shortly as we run the cars up on the new Cooksport in house 4WD Dyno Dynamics Rolling Road, something that our customers will be able to benefit from in the coming weeks.

Where to modify a GR Yaris

If any of the above improvements interest you for your GR Yaris, you will be pleased to know we not only supply them, but also fit them at our facility in Somerset, just south of Bristol and Bath. Come down and pay us a visit or contact us now on 01761 439 098 and

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