When we decide to create a new clutch system for an application, there are many factors that need to be evaluated before the chips start flying!
The first thing we do is evaluate the clutch that came in the vehicle. How is the pedal effort? Where is the engagement point on the pedal? Does it take much RPM to take off right now? Is there any chatter? Does the car accelerate well or feel like it lags? By evaluating these ‘driveability’ factors, we are better able to decide what the features and benefits of a new clutch system will be. This helps guide the R&D process.
For instance, the first time we drove a fifth gen Camaro, we immediately noticed that the clutch engaged right at the top of the pedal, and that the release length (point when the car begins to move on the pedal stroke, to the point when it is fully engaged) was very long. This actually led to the creation of another product that has become very popular, our Pedal Height Adjuster system.
The next step is to disassemble the car and evaluate the factory unit. Later model vehicles utilize internal hydraulics, so it is critical that we design our package to fit not only within the constraints of the bellhousing, but also within tolerances that will make it compatible with these factory hydraulics. We also look closely at the unit overall weight, and try to determine if making the clutch either lighter or heavier would be an advantage in driveability for our new unit.
Many of the later model clutch systems are much heavier than most people realize. The clutches in newer Mustangs, Challengers, C7 Corvettes, and Camaro’s are upwards of 55-65 lbs. These units are roughly 20-30% heavier than the assemblies found in earlier generations of these vehicles. The additional mass can greatly improve the low end driveabililty in today’s performance cars. Coupling this increased mass into a dual disc clutch system and you now have a setup with a relatively light pedal effort, great holding capacity, and nice smooth engagement and street manners.
Once the system is designed around the factory hydraulics, holding capacity, and pedal effort we then begin the process of machining the components and doing the installation. After the clutch system is assembled and tested in the shop we do the initial installation and begin testing the unit’s performance – in other words the fun part of our job!
So as you can see, we put a lot of thought into what we want a clutch system to be based on the vehicle itself. It is not enough just to take your last great design and adapt it, we must always be thinking ahead to the next great design!