Description
The only McLaren engine mounts befitting an exotic supercar, precision machined from billet aluminum, specifically for the McLaren platform. 300% more stiff and Lighter than OE McLaren engine mounts, with adjustable bushing options and the design flair expected from the only McLaren specialist company . 100% bolt-on and lifetime warranty. These are the same engine mounts found on our ABSOLUTE build packages.
CONTEXT
Most McLaren owners are unaware that the engine itself is only supported by two engine (dog-bone) links in the front of the engine. In addition to this, there is a lateral torque arm to counteract the rotational force of the crank itself on wide open throttle.
There are two versions of these engine mounts (plus torque arm) released from the McLaren factory to the public on various models. On the 12C and earlier 650S, you will see the more rough sand-cast aluminum mount (see pic below, top) and on the later model 650S through to the 765LT, you will see the smooth cast aluminum mounts with a brighter finish (see pic below, bottom):
While the engine mount body itself is an adequate design, the weak link has proven to be the bushings themselves. Flat plane engines, such as the M838 and M840 have more vibration at idle, hence why NVH (Noise Vibration Hardness) is a top priority when designing each McLaren model chassis.
To reduce NVH from the engine, McLaren chose a few of obvious paths:
- Bushing Material – Typical for OEMs, all McLarens use rubber bushing, bonded to a steel inner sleeve.
- Bushing Durometer – We measured the stock bushing durometer to be approx. 45 ShA (Shore Hardness A). This is relatively soft.
- Bushing Construction – The OE bushings has have large open voids of air (shaped as a plus sign), to further decrease NVH.
For McLarens at stock power levels, the factory engine mounts are probably fine for street use. However, for anyone looking for higher power and increased levels of torque, you will quickly understand the downside of this overly soft OE bushing design.
Any McLarens making over 750 lbs ft of torque, will see their engine lift about 40-65 mm while at wide open throttle. While this may not sound like much to some, it is an alarming amount when you consider that your throttle bodies are bolted to the engine (intake manifold). So your throttle body is moving up and down under load, while the other side of your intake tract, your intercooler, is hard mounted to the chassis (not moving).
This means that your upper intake boost hose has to absorb this large vertical movement AND deal with increased levels of boost from any tuning/larger turbos.
In reality, this caused us a lot of pain in the past with blown boost hoses, until we decided to design a better solution…
DESIGN PHASE
We chose to think outside the box and create a new engine mount design by incorporating a unique asymmetric top and bottom diagonal bracing. Through CAD simulation, we found this results in engine braces that are significantly stiffer while maintaining a weight below that of the original components.
This radical approach to the McLaren engine mount design, allows for a mount which is able to provide similar benefit to that of a more traditional cross brace design, without having to make compromises in weight reduction to control stress concentrations that occur at intersections of a cross brace.
By placing one portion of the cross on the side and one portion on the opposite side, intersection peak forces now occur inside the braces central core and within the thicker side walls. This allows for larger weight reducing pockets to be produced.
For the bushings, we wanted to make sure we gave the user all the options they needed out of the box. This includes a bushing option with the stock softness (45 ShA), a medium firmness (60 ShA) and a firm option (80 ShA). Every set of our engine mounts come with 3 bushings options out of the box that are completely user replaceable with zero tools required; to the credit of our two part bushing assembly.
We also opted to fill the empty void of the stock bushings to decrease decrease unwanted engine movement and include corrosion resistant stainless steel hardware with integrated engine spacers.
ENGINEERING VALIDATION
Through extensive FEA (Finite Element Analysis), we were able to compare the structural loads of the OE engine mounts versus our proprietary design.
Comparison of stresses between the stock component and our ABSOLUTE engine mounts during a bending moment. We were able to reduce internal stress concentrations through the use of higher grade materials, improved manufacturing techniques and an improved design, where forces are better dissipated throughout the component.
Comparison of deformation between the stock component and our ABSOLUTE engine mounts during a bending moment. This result shows the stiffer ABSOLUTE engine mounts results in less deflection, which increases engine control movement during high torque situations.
The end result of all this research and development are engine mounts which are :
✔ 50% Stiffer in Compression
✔ 40% Stiffer in Tension
✔ 30% Stiffer in Bending
✔ 60% Stiffer in Torsion
✔ 100% ABSOLUTE
PRODUCT FITMENT
