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smart fortwo Lowering Spring Set
451 model - MADNESS - Rear Set

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$149.99 Save $20.00
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SMART MADNESS Rear Sport Springs for your smart. The easy and economical way to even out the stance of your smart and improve the handling. 

Not everyone is interested in installing a complete set of Lowering Springs on their smart. Some just want a set of rear springs to even out the raised rear look of the car. We have had many requests from our fellow smart owners for a well made, affordable rear set of springs.


We have been working with a partner that specializes in manufacturing high quality springs and are now able to offer you the smart owner with a great option.

Why replace the rear springs you may ask?

  • Better Cornering Response
  • Improved Roll Resistance in corners and avoidance maneuvers
  • Lower Stance in the rear of the car


To accomplish these goals, we have worked together with our US Partner and Manufacturer and have developed a progressively wound spring set that directly replaces the stock rear springs of the smart. This was the best opportunity for improvement with the lowest cost and effort. While replacing the entire spring set has a number of additional advantages, this is a great budget friendly solution and one that may be right for you if you are looking to save some money.

Several designs we tested over a period of over 1 year and this proved to be the best combination of results. This set features a Progressive Rate Spring Design. The Progressive winding creates a soft initial ride quality, then becomes increasingly resistant the more the spring is compressed (cornering, stopping, accelerating). 


The improved spring rate in this rear spring design proved to be much better in resisting body roll through corners, improved steering response, lowered the rear stance of the test car by ¾”, providing a more level car stance and improving the rear wheel well appearance around the tire.


Other improvements were noted as well:

  • Reduced “Rocking” on acceleration and deceleration
  • Reduced Under Steer (Push) in Corners
  • Less Steering Effort
  • Reduced Front Tire Wear


A dramatic reduction in the “rocking” of the chassis was observed as the test car accelerated and slowed in city traffic. A significantly less under steer (Push) was also seen as the car entered corners. With the rear of the car sitting flatter through corners, the car responded with less steering effort, and more deliberate and stable performance. Less front tire wear was also noticed as time went by. 


These springs have been powder coated to resist road spray and corrosion.

Made in the USA exclusively for SMART MADNESS!

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About Manufacturer

MADNESS Autoworks is your One Stop Shop for customizing, accessorizing and servicing your favorite ride.

Whether you are looking for custom wheels, window tinting, custom stereo installation or other performance modifications we are your shop.

MADNESS Autoworks is located in Signal Hill, CA (an enclave surrounded by the City of Long Beach) and is a facility dedicated to making your favorite ride truly yours by offering a wide line of aftermarket accessories, installation and customizing services.

MADNESS Autoworks was originally known as SMART MADNESS a company that became famous for customizing and accessorizing smart cars.

SMART MADNESS has become the largest provider of smart car parts, accessories and customizing services in North America and now one of the largest globally in just a couple of short years.

We accomplished this goal by providing the very best in products and services at reasonable prices with a personal touch. We treat our customers like family members and do our best to make sure every one of our customers gets the very best treatment possible.

A number of our customers own other cars besides the smart car and continuously ask us if we would also work and or customize their other car due to their positive experience with us. This is how MADNESS Autoworks was born.

Our goal is simple! Provide you, the driver with the widest range of products, servicing and customizing options with friendly service at a very competitive price.

After spending years working on cars and working with many suppliers we thought at times we could do better by designing and manufacturing some products ourselves. We started partnering up with our most trusted manufacturing partners and suppliers, investing in infastructure, manufacturing equipment and recruiting some of the best tallent that could help us design and build superior products and make them available to our fellow drivers.

Our goal is to provide a top quality product that has been tested and used in our own cars and has proven to last and provide a good value for the investment. Whether you are looking for the best value in a set of floor mats, a performance exhaust system, an intake, a roll cage or a carbon fiber part the MADNESS Item is designed to deliver on our promise of bringing a good quality item at a reasonable price. We do not design and build our products to be the cheapest, we design then to be the best value for the money and stand behind them the same way we stand behind our work.

If you ever have a question, need assistance or have a request contact us and we will be glad to help.

Product Reviews

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