I haven't put my car on a lift yet, but just looking underneath..I seem to have headers. The pic below definitely looks like a header collector, and is longer than the stock exhaust manifold from what I've seen. I'm trying to figure out which ones I have, but until I get under I can at least figure out which ones I MIGHT have.

The car still has cats, and a Borla muffler which isn't supposed to be available for the dual exhaust cars (I thought...and this is definitely two in, two out).



What manner of beastie is it??

 

Another thing I noticed while peering under the car...don't all dual exhaust 928s have one pipe going around each side of the transmission? This where the pre-silencers go, at least on all stock (and most custom) exhaust pics I've seen. I have two pipes that are right next to each other, that together curve around the driver's side of the transmission and then into the Borla rear muffler..with no pre-silencers at all, just the cats, aft of the headers.

Very curious what exhaust system this is. Maybe just a one-off custom? I know it sounds nice :-)

 

Yes they are aftermarket headers. I don't recognize the headers from that shot, but someone probably will.
Isn't your test port making some noise hanging down there against the exhaust? or odor from the insulation burning through?

Anyway- the parallel duals were used in 85/86, both pipes running adjacent to each other from the cats, under the driver's side and back to the final muffler. 86.5 should have the S4 and up system.
Borla made several replacement systems years ago.

 

That looks like an MSDS header collector.

85 and 86.0 have dual tubes from the cat that run along the driver side, through a 2-in/2-out resonator and into the big old pumpkin muffler with the corner-exhaust tips. Stock 86.5 had a dual resonator setup flanking the transmission, but joining into a corner-exhaust muffler. The 86.5 resonator sections and muffler are unique to that (half) year.

Sounds like you have a custom resonator-less catback setup.

 

Thanks guys. It's interesting, trying to track down what's been done. Thinking ahead to future mods (i.e. getting way ahead of myself lol) I'm guessing there's no simple x pipe I can swap in for the cat section on an exhaust like this?

I haven't heard or smelled anything that weird, but there are a number of odd noises coming from this car still, so who knows? Stupid question of the day: What is this "test port" thing, anyway? And where should it be mounted?