how do u tell if you have an aftermarket MAF sensor or throttle body on a 2001 Z28

 

They look different than stock. Now, if someone modified stock parts (i.e. home port the tb or descreen the maf), you can't tell unless you take it apart and peak inside. Most companies like to put their brand on their products though. If you have a BBK throttle body or an SLP MAF, it'll be obvious.

 

stock on the left...75mm wide...and aftermarket 85mm unit on the right



here is my ported TB...you can see a smooth transition from the sloped front, to just a flat inner bore. there is typically a lip just in front of the blade (when closed).


here is a drawing i did on how it helps...it may explain it better