Sprint Filter P08 Air Filter for Road & Track – Zontes ZT 310-X (2021–2023) SM277S

Two figures get quoted for this element and they are easy to run together. The weave is rated at 80 µm; the polyester threads it is woven from are around 22 µm across. Neither number is a hole that sorts particles by size, and neither is a promise that everything smaller passes through untouched. Filtration is a percentage, not a gate — and reading it that way changes what you expect from the part on a ZT 310-X.

Key Features

• Rated 80 µm with a flow figure of 5,050 l/m²/sec, in one dry layer
• Retention measured at 93.13 % of 100-micron particles; four-layer oiled cotton returned 76.42 % on the same test
• Polyester filament of roughly 22 µm diameter — the thread thickness, not the mesh opening
• Slots into the series airbox as it is, with no adaptor and no remap
• Approximately double the filtering area of a comparable performance element
• Dry, washable, reusable; backed for two years from purchase

A rating is a statistic, not a sieve

Particles do not queue up and get measured. They are caught by three separate mechanisms: the largest are simply too big to pass, the middle range is intercepted by brushing against a thread on the way past, and the finest are carried into a fibre by their own inertia when the airstream turns. That is why a mesh figure and a retention figure are different statements, and why the honest way to compare media is the measured percentage rather than the micron number printed beside it.

Where the area comes into it

The flow figure is quoted per square metre — a rate, not a total. What a housing actually flows depends on how much fabric has been folded into it, which is where roughly twice the usual area matters: the same demand spread over more surface means lower velocity through the weave and a smaller pressure drop for the same amount of retention. It still does not make a standard ZT 310-X quicker, and no drop-in element will. Finer cloth holds back more and flows less; coarser does the reverse. It is a trade, not a ranking, and the P08 sits deliberately at the free-flowing end of it.

Care and cleaning

An air line does almost all of it: aim at the clean side, work outwards, and let the dust leave by its entry route. Water and a mild detergent deal with anything oily; rinse until nothing more comes out. The element must then dry in ambient moving air — heat of any kind is what destroys it — and be refitted dry. Nothing is ever applied to an SM277S, before or after cleaning. Sprint Filter's sheet is in the Downloads tab.

Fitment & Compatibility

Fits the Zontes ZT 310-X built between 2021 and 2023. The same element is catalogued for eight further Zontes models across three capacities, the 350 line running through 2026. Order on the element code with the model year checked against the range.