I'm putting an 87 n/a into my 84 gslse. i just took the exhaust mani off the 87 and it has that extra hole.. what is that? I already have a header from the SE and was wondering if it'd be alright to use it on the 87.

 

Extra hole on the collector? if its there, thats the o2 sensor bung

 

i meant the hole when you take the manifold off. It's like an extra spot for exhaust to come out.