Over the years of having this kit out there, there have been a number of continuing questions about the belt tension. There have also been some pulley failures. I thought I would take a minute to address this.
The pulley failures are a result of too much belt tension. The Dayco pulley used is designed to service 100k miles of use. This assumes that there isn't too much side loading on the bearing. Unfortunately some installations have resulted in too much side loading. I now know how this happens, and it is a direct result of failure to follow instructions.
The instructions clearly tell the installer to use the center link of the OEM tensioner if the belt is too tight. I have always said that less tension is needed on the belt than in stock configuration. I guessed about 80% of the tension setting would do it. Regardless, if there is more tension than stock, which can easily be read with any of the tools, then clearly it is too much. Many of the installations resulted in the use of a prybar to get the Tensioner that came with the kit installed, with some really struggling to get it in there. This is a clear indication that it is too tight. This is the point at which the center link should be changed to the OEM unit, and be used with the heim joints and jam nuts that came with the kit.
Failure to take this step has resulted in a number of pulley failures. I thought it was 12, but after going back over my records, it seems more like 8 or 9. Still that is too many. This is completely avoidable.
Further, the Belt Guard may require the bolt holes to be drilled out larger, so that the Belt Guard may be raised to create further clearance from the belt. It may also need a bit of "tweaking" to create clearance. This will in no way reduce the effectiveness of the Belt Guard.
In the end, the belt need only be tight enough so as not to slip. Slippage will show up on a boost gauge.
If it makes anybody feel better, I too created a failure by over-tensioning the belt. That's how I figured this out.
94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating
www.968forums.com
"It isn't nearly as expensive to do it right as it is to do it wrong."