What’s wrong with my stock motor mounts?
Motor mounts are an unseen and often neglected part of your vehicle’s powertrain. A properly designed mount in good condition isolates the chassis from engine vibrations by absorbing them in resilient rubber. Then, during acceleration, the mount must still be solid enough to hold the engine securely to the chassis, avoiding the loss of rotational energy that would otherwise be delivered to the rear wheels. It’s a lot to ask from some rubber and steel.
Unfortunately, the motor mounts used on most muscle cars and collector cars used a very poor design, commonly referred to as the “sandwich” design (see illustration). This design typically provides good isolation from engine vibrations but stretches under acceleration. This wastes horsepower and eventually causes the mounts to rip and fail, often resulting in engine compartment damage. Many modern motor mount designs used in late-model vehicles provide a fair compromise of these factors with an "enclosed” design (see illustration).

While “enclosed” mounts are safer, lifting force compresses rubber, causing
power loss and destroying rubber
Such designs provide a solid steel external enclosure with a rubber center through which the engine is attached to the chassis. This design compresses rather than stretches the rubber during acceleration. The enclosed design is an improvement over the sandwich design because compressing the rubber conserves more energy than stretching, as with a sandwich design. Enclosed mounts also do not fail violently, as do sandwich mounts, so there is generally no engine compartment damage.
If DynaTech makes mounts for your muscle car or collector car, it means your stock mounts are of the “sandwich” design. It is ironic that your car is expensive to restore, has a high-torque engine, and yet has the worst possible motor mount design! Yet that is the case. Making the case worse is that most muscle car and collector car motor mounts are no longer in production from the OEM manufacturer. This means you must purchase mounts from aftermarket sources. Most aftermarket mounts are produced overseas, and the quality of rubber and production varies greatly. As difficult to replace as your motor mounts are, and considering the potential expense when your mounts fail, you don’t need just a good quality mount; you need a better design.
What makes MityMounts® different?
To develop a motor mount worthy of your car, DynaTech engineers considered variations on the “enclosed” design, but found rubber compression on this design also led to early failure under extreme conditions. Additionally, power loss due to this compression still occurred, just to a lesser degree. An entirely new design concept was called for. What DynaTech developed was its patent-pending Lock-Up® motor mount design (see illustration). This design provides the safety of an enclosed mount design, but also provides a direct steel-to-steel lock-up under acceleration. Power is transmitted without excess motion and resultant power loss. Clearances for headers and other tight-fitting components can be closer due to this reduced engine motion. But engine vibration and harshness during normal driving is isolated from the chassis just as well as with stock motor mounts. Mity-Mounts® bolt in with no modifications and look exactly like stock motor mounts when installed.
Why not solid motor mounts?
It seems paradoxical, but solid steel motor mounts actually fail very frequently. There is a very good reason why auto manufacturers use rubberized engine mounts; they prevent transmitting vibration and noise to the chassis. Solid steel mounts transmit so much vibration that they fatigue and crack the mount brackets and sometimes even cause cracks in the engine-mount crossmember or engine block itself. This is not to mention the discomfort of driving a vehicle that is much more noisy and vibrates excessively.

“lock” on acceleration to provide safety and transmit power efficiently

What about urethane mounts?

Urethane has been the buzz of the suspension industry for many years now. Because it is firmer than rubber, it is well suited to suspension bushings in high-performance applications, since it “gives” less during hard cornering. However, this very feature that makes urethane a good material for suspension components can cause problems in motor mounts. Remember that a motor mount must have considerable “give” to absorb engine vibrations. DynaTech tests have shown urethane to have a tendency to “shear” in motor mount applications, particularly in vehicles with high-performance engines that have long-duration camshafts.
Watch out for imitators!
DynaTech’s patent-pending designs are precision engineered for each application. Computer model simulations are run using typical power curves for each manufacturer’s popular powertrains. This is very important since each manufacturer’s engine “cradle” causes torque to be applied at varying angles, thus varying the tensile and shear loads that are applied to the mounts.
Remember to ask for the proven quality of the original. MityMounts® are made using superior materials. Only MityMounts® are designed and tested to our rigorous standards. Only MityMounts® are backed up by a lifetime warranty. Don’t settle for less!
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