Pads for Harrop 4-pot (HSV / Porsche window).
Fits: Harrop Ultimate 4-pot, HSV Harrop, Porsche-window Harrop.
Same shape. Very different pads.
Every compound below bolts into the same Harrop 4-pot (HSV / Porsche window) caliper. What separates them is operating temperature and friction — a sprint pad that needs heat in it will feel wooden on a cold first lap, and a road-biased pad will fade before the end of a long race. Figures are the manufacturers’ own published data.
WinmaX W5
2 options · from $405WinmaX’s standard circuit model, and the default club racing and rally choice in the range.
100–750°Cµ 0.40–0.43Usable from coldcircuit · trackday · sprint · rallyWinmaX W3
1 option · from $362WinmaX call this their most versatile pad: sportive street through to sprint racing. It is the W-series compound we stock most of.
0–650°Cµ 0.34–0.37Strong from coldstreet · trackday · sprint · hillclimb
Figures are the manufacturers’ own published data for each compound. Where a brand doesn’t publish a figure we say so rather than estimate it. From cold is our reading of each manufacturer’s published minimum operating temperature, not a separate rating they publish. Manufacturers test on their own equipment, so friction numbers are best compared within a brand rather than across brands. Not sure which suits your Harrop 4-pot (HSV / Porsche window) setup? Ask BuildBot or email us with your car, class and typical session length.
WinmaX compounds (3).
One shape, every part number.
These part numbers all share the Harrop 4-pot (HSV / Porsche window) backing plate. The suffix is the compound (and plate thickness where the shape comes in more than one) — ask us or BuildBot which compound suits your discipline.
| WinmaX | WMP719-15.5-{W3|W5} · WMP719-20-W5 |