Designing an automobile is an almost unimaginably complicated undertaking – despite the fact that most of us think that if we just had the time and tools, we could build our own car from scratch, the reality of the situation is that even the most humble economy car is the work of a legion of talented engineers over the course of tens of thousands of hours.
The design process also has to factor in a whole list of trade-offs too; power versus fuel economy, quality versus cost, and even ease of manufacture versus easy service in the field. Even when it comes to luxury vehicles, if it’s mass-produced and has to meet a price target that normal folks might be able to afford, the design will embody compromises.
The current CTS-V is a radical shift from Cadillac’s previous line-topping “performance cars” in that the car was more than a powerful engine in a so-so chassis.
Based on the Sigma II platform, the current CTS-V is a radical shift from Cadillac’s previous line-topping “performance cars” in that the car was more than a powerful engine in a so-so chassis. It was designed from the outset to offer both comfort and handling to go with the immense power provided by the LSA under the hood.
There Are Always Tradeoffs…
In the case of the CTS-V, we’re going to look at one very specific area of compromise: The engine mounts. The LSA produces 551 pound-feet of peak torque, and thanks to the Eaton TVS blower strapped to the top, it has a torque curve as flat as the Kansas horizon. The engine mounts had to be designed to withstand 100,000-plus miles of normal use, which in the case of the CTS-V was sure to be, shall we say, “spirited,” yet not shake like a wet dog at idle.
As a result, the stock engine mounts were a compromise – soft enough (and properly tuned) to absorb vibration at idle, stiff enough to keep the engine from twisting in the chassis at full throttle. Beyond that, the design of the subframe that both supports the engine and provides mounting points for the front suspension was also designed with ease of production as a priority.
Assembled separately, the subframe, engine, and suspension are all “married” to the car body on the assembly line, making access to the mounts on the complete car difficult, to put it mildly.
The Energy Solution
What all of that adds up to is twofold: First, the stock engine mounts, which are fine for normal use, start to show signs of distress pretty quickly when the boost gets turned up. The LSA has shown enormous potential with even relatively mild upgrades, as a look at our CTS-V project car will show. Keeping the engine firmly rooted helps the rest of the driveline stay healthy, in addition to transmitting power more efficiently instead of wasting it tying the engine and transmission up in knots.
Secondly, because motor mount installation on the CTS-V requires dropping the subframe to get access to the fasteners, this is NOT a job you want to do twice. Replacing worn factory mounts with new OEM-spec ones just resets the clock on the next labor-intensive round of service. Much like clutch and transmission work on C5/6/7 Corvettes, this particular job on the Caddy should be done once, and done right.
Energy Suspension claims the title of “world’s largest manufacturer of performance polyurethane automotive components,” and most enthusiasts have encountered their suspension bushings at one point or another in their gearhead lives. They also make a broad assortment of engine and transmission mounts, and in the case of the CTS-V, their PN 3.1155 mount set is a far cry from the relatively wimpy OEM parts.
Made from billet aluminum and their proprietary Hyper-Flex polyurethane formula, the Energy CTS-V mounts are clearly intended to be both far more durable than stock, and look like a “lifetime part” to us that won’t require replacement down the road like the stockers. Energy doesn’t pull punches about these mounts – they admit they are one of the most difficult-to-install parts in their catalog. But when replacement is necessary, either as preventative maintenance in anticipation of a power upgrade, or to replace blown-out OEM mounts, it makes sense to use a part that won’t need to be replaced again.