Stock muffler exploded (spectacularly!) a while back. Original 12a, PO took out cat and put in what appears to be a glasspak. Whole system is a cobbled mess. Thinking universal RB, 2 or 2.5" diameter pipe all the way back from stock manifold. Supposedly some PO did a street port but don't really know. If it still sounds bad, can go back and add a presilencer I guess. Good plan?

Ya know, I'm not even sure it's a stock manifold, could be a header of some sort.

 

if its a big chunk of cast iron then its a manifold. if its 2 pipes its a header.

 

It's probably a header then, not sure what a stock manifold looks like. I haven't looked that closely, maybe the owner is watching this thread and he remembers, I'm just his mechanic.
If this is a 12a stocker, then we ain't got it, must be a header.

 

Ive only seen one,(in a wrecking yard) but there are some FB's that have a factory "header" manifold, instead of the heavy reactive iron manifold. Its basically an unequal length, heavy steel header...... might be on some Fed or Canadian cars.

 

Steve, you might have seen the 6 port 12A exhaust manifold. It looks like a mini header. It has a backpressure or emission sensing tube inside like the FC manifolds do.

 

Looks like a Pacesetter to me. 1 7/8" pipe in most places. I think we'll do a RB universal with 2.5" inlet, all 2.5" pipe from header back to it and if it sucks, cut it and put in a presilencer. Plan?

 

Just buy the rb system second hand problem solved. Pacesetter is garbage and will rust out. Sounds terrible. Flows bad. So in short... Find a second hand rb header and silencer. Then take your stock muffler in for parts to a welder and an rb universal muffler. He can cut the flange and mounts from it.