Weight reduction and rotating mass – reduce your cars weight for more fun!

You want to have fun in your car, and have some enjoyment in the twisties and corners.

People are very often concerned about making more horsepower, having a better sound system, etc and one area thats frequently overlooked is the weight of the car, and more specifically rotating mass weight.

Now, any car can benefit from a weight reduction, but how extreme you want to take it depends on you.

Take for example our 2014 Dodge Dart GT.

One of the things we did to change our cars look, was to get a set of 18 inch Enkei PF01 wheels. These replaced the factory Dart GT wheels that looked like this.

Now, we dont have exact weights available at time of making this article, but the factory GT wheels were very heavy, and weighed something like 24/25 lbs each. The Enkei wheels we put on that you can see below weighed in at 18/19 lbs. Thats a savings of about 6 lbs on each corner.  That may not sound like much, but a 24lb weight savings on wheels is massive.

Now, with these new wheels, we noticed a difference in acceleration off the bat, the car handled better, it revved up much faster, and felt faster overall. This is because, in general anything that is rotating mass – ie, wheels, tires, brakes, axles, rotors, engine internals directly affects the engines performance.

Now, we also did some other work to our Dart to reduce weight.

Brakes – we used a custom made brake kit to reduce 16 lbs of rotating mass.

Pulley -we installed a lightweight crank pulley to reduce 3 lbs of rotating mass.

Seats – we pulled out the leather seats and installed cloth seats to save nearly 30lbs of weight. Most of the weight savings were from going from full power seats to manual seats, no heavy motors attached to the cloth seats!

So, we have reduced nearly 50lbs of rotating mass, and about 30 lbs of fixed mass. This is pretty incredible and its a difference you can feel when driving our Dart.

Morale of this story is – when you are modifying your car, keep the weight in mind!

Or, to quote the founder of Lotus automobiles, the lightweight, fun roadsters –

“Simplify, then add lightness”!



Written by Modern Performance

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