Adjustable height lowering springs

                21.5mm bolt-on wheel spacers


The standard GR Yaris has been met with high praise the world over. Having covered many miles in our own development car, we agreed that the stock car was an exciting recipe. However we knew that we could improve upon the standard spring setup without spoiling the work that Toyota have done on their dampers.


Working with Eibach, we assessed the OEM setup and knew that we wanted to maintain the road manners and compliance felt on the standard springs. In addition, we wanted to reduce weight transfer to help improve body control during performance driving on the road and track through lowering the car’s centre of gravity and some subtle increases to spring rate. Finally, we wanted to provide the ability to cornerweight the car for fine-tuning track handling.

Our adjustable height performance spring kit utilises dual-rate springs front and rear, manufactured by Eibach, to help maintain compliance when the wheel travels from rebound into bump.


After testing on both the road and track with GT3 driver Jonny Cocker from JCR-Developments we settled on spring rates which are increased by 15% front and 20% rear over standard. The increase in spring rates and slight additional rear bias work together to reduce weight transfer, improving direction change, turn-in response and rear axle support mid corner.

Our black anodised aluminium bespoke adjusters sit over the OEM dampers and allow up to 35mm of ride height reduction over standard, allowing the driver to tailor their car’s height to their own preference whilst opening up the possibility of corner-weighting for optimal balance on track. The adjusters use an allen-head pinch bolt to lock them in place.


We offer full fitting and setup of the spring kit, with ride-heights, cornerweights and geometry set to suit the customer’s requirements and usage. 

Examples of Yaris' with the spring kit fitted

Technical Specs Overview

Engineered and developed in-house at String Theory Garage, with Eibach & JCR-Developments.

  • Ride height change

    • Front: Up to -35mm​*

    • Rear: Up to -35mm*

  • Spring rate changes

    • Front: +15%​

    • Rear: +20%

  • Dual rate springs both front and rear, fitted with polyeurethane clip tubing to prevent coating wear

  • Springs manufactured by Eibach Germany to industry leading tolerances.

  • Anodized aluminium adjusters compatible with standard dampers and top-mounts



  • Kit only

We ship worldwide - get in touch for a quote.

£695 inc VAT

  • Kit

  • Fitting

  • Ride-height set

  • Cornerweighting

  • Alignment

at String Theory Garage

£1095 inc VAT

What our customers think...

"Amazing work, ride quality is still excellent but handling is off the scale. The car is absolutely planted. The standard car was already very good but String Theory Garage have taken it to another level."



"Exactly what I was looking for. Flatter when cornering, much more stable when driving more spiritedly and the road has undulations, the car does not bounce like it did before. "



"Your suspension is a game changer. Handles much better on the road, much less front body roll and gives you much more confidence to push on. Can't wait to get it on track".



21.5mm bolt-on wheel spacers

When reducing the ride height using our spring kit, it was evident that the standard wheels fell a little too far in the arches. To provide a fully purposeful aesthetic, we knew the wheels needed to sit further out to fully fill the arches.

We tested some readily available 20mm bolt on spacers, but found that the OE wheels studs just touched the back of the standard circuit pack BBS forged wheels, despite having cut-outs in the back of the rim. This made fitting the wheels impossible as they would not sit flush to the hub.


As such, we have designed our own 21.5mm bolt-on spacers. The additional 1.5mm thickness is enough to clear the OE studs on the standard wheels, whilst still retaining clearance between the tyre and the inner arch. 

Made from 6082 billet aluminium in the UK, anodizied black, these provide the perfect accompaniment to reduced ride height. Supplied with nuts to attach spacers to OE studs, the standard wheel nuts can be used to attached the wheel to the spacers.


21.5mm bolt-on wheel spacers

  • 21.5mm thick

  • 5x114.3 PCD

  • 60.1mm centre bore

  • 6082 billet aluminium

  • Supplied with nuts

  • Set of 4

We ship worldwide - get in touch for a quote.

£265 inc VAT