OK, so I'm missing one of the bolts that connects the header to the downpipe and I was wondering if anyone knew what kind they were. It's a square tip and there's no head on them...if you look from the top of the engine bay down at the downpipe.

Edit: There is no nut on the topside either, so I have no idea how they are staying in.

 

I might be missing something, but it sounds like you're describing a stud. Usually, they don't have a square shank on the end, but it would help to install them.

Did you buy a replacement mannie? Very often the stud will back out due to rust on the nut. Just get a new one from Honda or a wrecking yard (maybe even a parts store).

 

I know what you're talking about on the engine block....it is not that. I have an after market header and it's a 2 piece. The part where the downpipe and the header connect is what is missing. I guess I can just buy three bolts that will fit in that hole and put nuts on the top....

 

just take one of the other studs out and take it to a parts store and get them to match up the stud and bolt