Not sure what this noise is

Had the exhaust checked out today, the flange from the header to the exhaust is alright.. it appears the header to engine gasket is leaking. I tried the hose trick but couldn't hear it. Once the exhaust was blocked off the leak could be heard. Sorry for the terrible video. The car is sluggish between shifts, which is probably normal being a stock 87 318 w/ a holley 750 carb on it.