Its quick and easy lol, will a B17 header fit on a B18c1?

Also is there a real difference between a 4-1 and a 4-2-1? Like performance wise?

I ask bc I have been searching for one for my GSR bc it has a hidious stock header where the previous owner for some reason took off the heat shield

 

i'm not sure if the b17 header will clear the b18c1 oil pan but here's the deck height;

b17: 203.25mm
b18c1: 212.39mm

so 9.14mm difference. go grab your measuring tape.

i think 4-1 improves top end/peak power whereas 4-2-1 improves midrange.