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Maf Diameter

1141 Views 4 Replies 4 Participants Last post by  craig_c23

Does anyone know what diameter the ST MAF is? I didn't want to take my air box off just to check. I'm contemplating trying to make a home brew induction kit with a filter I already have just to see what it's like. If it doesn't work then I'll fork out on a proper one
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thats what im doing to bud

going to use the RS ecu holder to relocte it out the way then run the biggest filter i can really get in the space behind the head light keeps it nice and high from water and should be a good airflow to it.

so ill measure up get the biggest filter a 90/45 deg bend boost hose to fit to the maf along with a bracket to hold the filter steady bobs your uncle, noise will be immense and will do the job only hassle with heat soak would be a hot day sitting in traffic but i don`t commute so couldn`t give a
bout that.
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MAF inlet is 78mm, outlet 80mm - I've done a similar induction mod and used a 76mm diameter section of Samco to go onto the MAF as the 80mm size was being closed up too much. The 76mm pipe is a tight fit but will go on with some persuasion and a bit of patience.

Few photos of mine here

Plus you might want to look at what Glenn has already done if you've not already seen it
Thanks for the Tips guys, looks like the main expense will be the RS ECU cover
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