I use P21S gel wheel cleaner. It's very effective, easy to use, and it's a non acid based product...It's also Porsche recommended... I purchase my detailing products from Autopia.com, great customer service...
P21S here as well, I'm using the less intense spray version.....works real well!
Lou
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1998 Guards Red Black/Black 5 sp.
Work done '06 :Replaced bad hose and clamps from reservoir tank
oil change and filter
replaced seals on both cam covers
brakes bled and refilled
Replaced bent rear right lower control arm
Front air dams and 3 underbody panels replaced
Halogen headlamps replaced