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In today's automotive market there is a trend of increasing under-hood temperatures. There are package space reductions and engine innovations which contribute to these temperature increases. This trend directly affects heat-sensitive components such as engine mounts, which are traditionally made with natural rubber. Paulstra now has hydraulic engine mount technology which takes the next step in heat resistance. This technology was developed in response to BMW's desire to place a new high performance engine on a common chassis. Instead of increasing chassis complexity to relocate the engine mount away from heat sources, an engine mount was developed which could resist temperatures up to 200°C. This paper describes the design, performance, and considerations of this new technology in engine mounting. This is the first silicone hydraulic engine mount to be manufactured in North America.

Paulstra's Linkeo Exhaust Decoupler was presented previously as an insulated, soft component that allows for better isolation between the engine and the exhaust line, and has the benefits of an insulated decoupler (more efficient catalysts). The industrialization process has included a 6DOF validation test. This test included: 1) 6DOF RLD displacements taken from an OEM proving ground, 2) high heat gas flow (850 deg C at 180 g/s), and 3) regulated environmental external temperature via chamber surrounding test sample. We will review details of this test and other validation testing that has taken place recently.

The automotive market has never been more “in-tune” with the end customer's comfort expectations. The need for advancement in suspension technology has grown exponentially in last several years. From various versions of link suspensions, to Magne-Ride®, the OEM is able to tune the same car for various drivers, to obtain ride performance ranges that include “sporty feel” to “luxury ride”. Paulstra, one of the main suppliers of anti-vibration parts, has added to this market trend with advancing control arm, trailing link, and twist beam suspension bushings from using standard conventional natural rubber as the isolating elastomer, to durable hydro-bushings that add high damping at a specific frequency to address smooth road shake and other ride tuning issues.

The need for fuel economy gains is crucial in todays automotive market. There is also growing interest and knowledge of greenhouse gases and their effect on the environment. Paulstra's magnesium powertrain brackets were a solution that was presented not just to reduce the weight of the engine mounting system (which was already under its weight target before magnesium introduction), but in response of the OEM's desire to further reduce the weight of the vehicle for CAFE and weight class impact. This new engine mounting system has three powertrain mount brackets that are high-pressure die cast AZ91D magnesium alloy. This paper will show that these brackets to have a dramatic weight reduction compared to the standard aluminum die-cast material that they replaced. This paper describes the process of approval: concept and material sign-off by the OEM, FEA for strength and modal performance, corrosion, and the final product.

Driveline (torque tube) boom, excited by a V6 powertrain’s 3rd order pulse signal, can produce high sound pressure levels in a vehicle’s cabin. Past solutions that have been used as countermeasures include; adding mass, tuned mass absorbers, isolating the torque tube with cardboard or other media, and using an elastomeric isolator (between the torque tube and the body). Specifically, we will show how to properly address temperature variation as it applies to tuned mass absorbers in driveline/torque tube applications, as well as show how to minimize production variation by using a robust design for the tuned mass absorber. Documentation will be shown detailing how higher temperature elastomers (silicon, EPDM, etc.) compare to natural rubber from a temperature variation standpoint. This is critical to the design of tuned mass absorbers as they apply to sensitive structures that require high damping levels in a narrow frequency bandwidth.

When designing an exhaust suspension with a flexible exhaust decoupler, the design engineer may want to use the device to decouple motion of the powertrain from the exhaust system. Today, durability schedules and the limits of existing metallic components keep current market flexible decouplers' stiffnesses high. A new elastomer-based flex decoupler (LINKEO™) has the ability to keep stiffness low in order to minimize the transmission of engine motion to the exhaust system. This will aid designers in making the exhaust suspension stiffer thus minimizing the motion in the exhaust line. This could improve durability of the system, and will minimize the required underbody package space. NVH testing has shown that accelerations can be reduced by 8-12 dB at targeted rpm ranges. Data will be presented to show how an insulated decoupler could favorably effect and improve emissions.

When designing an exhaust suspension with a flexible exhaust decoupler, the design engineer may want to use the device to decouple motion of the powertrain from the exhaust system. Today, durability schedules and the limits of existing metallic components keep current market flexible decouplers' stiffnesses high. A new elastomer-based flex decoupler (LINKEO™) has the ability to keep stiffness low in order to minimize the transmission of engine motion to the exhaust system. This will aid designers in making the exhaust suspension stiffer thus minimizing the motion in the exhaust line. This could improve durability of the system, and will minimize the required underbody package space. NVH testing has shown that accelerations can be reduced by 8-12 dB at targeted rpm ranges. Data will be presented to show how an insulated decoupler could favorably effect and improve emissions.