Type 4 Clutches
This page was last updated Thursday, June 03, 2010
Pressure Plate | Disc | Recommendations
I urge that along with this article, you should also read my tech article on flywheels. These two articles go hand in hand and you will need to read both to make a decision about clutches and flywheels.
Once you've got a fire breathing Type 4 with all of the goodies on, you'll want to use that horsepower. This is the job of the clutch. The clutch choice is important, as too light duty a clutch setup and you'll warp both the clutch and the flywheel, and you'll go no where. Too heavy a clutch is hard on the driver and the engine/transaxle mounts, and the rest of the drivetrain.
It is critical to realize to realize when dealing with clutches, that are two different styles of clutches for the Type 4. This relates to the flywheels in that there is a 914 clutch setup and a VW clutch setup. Unless you plan on running a 914 or 911 transaxle in your project, you will need to run a VW style clutch.
The VW clutches were available in 4 different diameters: 200mm, 210mm, 215mm and 228mm. The 200mm is the same pressure plate and clutch disc as a Type 1 200mm, so any of the high performance pressure plates and discs could be used. But keep in mind that a larger diamter clutch does not require as much spring pressure to stay connected. In other words you can have a softer pedal with more clamping power than a stock 200mm by using a 215mm or 228mm stock clutch. If you decide to use the larger clutches (210-228), make sure your transaxle is setup for the later style throw out bearing with the sleeve mounted in the transaxle. The pressure plates are only available without the ring in the center. I was told that Carter's Gearbox sells an adaptor that converts an earlier transaxle to use the later style throw out.
When it comes to clutch discs, there isn't much choice. For the larger size (210mm-228mm) the selections are pretty limited to the stock discs. The only things to keep in mind is selecting a rigid vs. a sprung disc and the quality of the disc. The sprung disc features springs in the clutch disc that makes engagement smoother and relieves the drivetrain the shock of the abrupt engagement. The problem is that with "spirited" driving the springs can fail. As to the quality issue, a well built disc, from a recognized brand can provide thousands of miles of spirited driving. Get a low quality disc and wait for the inevitable failure.
You'll notice that drag race cars will use three puck clutch discs. Three puck discs can be very violent and has been known to rip apart transaxle mounts. The 3-puck disc does not have a gradual bite, it is either engaged or disengaged. So on the street there's no riding the clutch in traffic or having a smooth take offs. This violent engagement/disengagement is also hard on the engine and transaxle. 3-puck discs will require regular flywheel resurfacing to maintain a flat, unwarped engaging surface.
As for recommendations, it all matters upon which transaxle you are planning on running and what state of tune your motor will be in. For the average Type 1 transaxle and a stock-mild 2.0, I would run either the 200mm with a Stage 1 Kennedy pressure plate with Berg Dual Friction solid center disc, or a stock 210/215 clutch. The 210/215 will probably require the bell housing of the transaxle to be clearanced. The 210/215 would probably be the cost effective option, as the original 200mm flywheels are difficult to find, the KEP 200mm flywheel is expensive, and the 210/215 clutch pressure plate/disc is more expensive.
If you plan on running a Bus IRS transaxle (002 or 091), go for the big one and run the 228mm pressure plate and disc. If you've converted your car to use the Bus IRS transaxle, chances are you going to doing some rough things with the car and will have a serious engine motivating it. I don't recall right now what's available for high performance pressure plates and discs for the 228mm, but make sure you buy something that will take the horsepower you anticipate on making. Quality parts will mean you've got control for that fire breathing monster of a Type 4 behind you.
Finally, if you are building a racing vehicle of some sort, like a drag racing or sand dragging, use a high performance 228mm pressure and a 3 puck clutch disc. This setup will give you the maximum holding power available and will get you to the finish line. I wouldn't recommend running this setup on a street car or dune cruiser.
