This is a reply to my mention of Volks Conversions' bolt-on rear-disc kit for Vanagons. A very useful reply!

Andrew,

In regards to the Sherman disc brake conversion kits it is my opinion that they are pretty much useless. I have had one on my 68 beetle and they provided less stopping power than the drum brakes. I am studying mechanical engineering so I did some calculations on the caliper backing plate and found it to be totally under designed for its purpose. He makes the caliper brackets out of a flat piece of Mild steel plate that I found was flexing and distorting due to the torsional forces created when the brakes are applied. This is because the centreline of the brake disc is offset to the centreline of the caliper bracket mounting position. The quality of the brake disc castings is also very poor, I found multiple pinhole imperfections in mine. I subsequently found out that John Sherman has no engineering qualifications, he is a motor mechanic. After talking to a number of other people I have also been led to believe that his adaptor plates are not of the best quality, one guy had his mainshaft needle roller bearing in his trans destroyed after a month of operation due to misalignment of the location dowels in the adaptor plate, in other words the crankshaft centreline and the mainshaft centreline were out of alignment. I am not trying to put down any of John's products, I am just making everyone a little more aware.

thanks

David Muir-McCarey Brisbane, Australia