GROUP 5 ARCH IN FIBERGLASS, set of 4 - This arch kit sticks out 3" and is used when body line is cut away or retained. Originally as a group 5 arch it was made for cars with no modifications but has become a cheap jack of all trades especially when large odd size wheels are used. Rear arches stop at bumper seam line. Widest part at front approximately 5.5". Fiberglass is finished in black gelcoat and is held on by screws recessed into the flare.
The quality of the arches is commensurate with the price. Most arches have minor flaws and require trimming for a perfect fit. The more expensive arches are obviously better quality and fit.
By fitting one of two types of sealing rubber available between the body and the arches, it makes fitment easier and a better finish quality is obtained, unless they are being moulded to the wing. 37H9871 (black, sold by the inch) is for edging trim that has only the edge butting against the bodywork.
Arch widths are measured off a new car and is the distance from the front wing (not the seam) to a point above the center of the front wheel, which is also the top center of the wheel and arch opening.
Rear wheels usually appear to stick out further than the front owing to the general bodyshape, so allow an extra 1/4" with most arches.
Widths when fitted are also dependent on the height arches are fitted and manufacturers trimmed sizes but should only vary 1/8-1/4" when fitted at the lowest position. Allow 1/8" for a rubber seal.
**Never drill the bodywork until you are satisfied with the style, fittability, and trimming requirements for a good fit!**