nope, its 80mm
I thought it was 76mm so ordered the 80mm Jetex filter (FC0001?), 80mm alloy joiner and a 80mm - 76mm silicone reducer just because I was too lazy to take the MAF fitting off and measure it.
Needless to say, it took a bit of shoving to get the reducer on
The bit of the maf housing that the wiring clips onto measures 76mm (which is what I went off), but once you remove the airbox you will notice that the end diameter (where you would attach the silicone hose/filter) bit is wider