In this video we remove and install exhaust manifold on 99 chevy p30 RV. doing the headers isnt easy but doable. didnt even remove the tire or jack the vehicle! engine oil dipstick tube has to be removed and reinstalled to do the the job. this engine is a vortec 7400 or a sixth generation 454 big block Chevy, 7.4 liters of displacement. the dorman 674-390 is the exhaust manifold i used to replace the stock one, the hardware was crap that was included, the threads where not made correct on the first one and it cracked the manifold when i put the wolverine strength on it. correct hardware is 3/8-16 at about 1.5 inches in length. rv exhaust is nearly silent and i forgot to put clip of motor sound, 2 cats and a large muffler then exits in rear, not much BBC rumble.
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It looked like you were missing some studs. Did you just use bolts when reinstalling?
Not a legit title by saying headers, this isn't a header job but a exhaust manifold r&r
My 1994 Fleetwood 454 had a slide on clip that held it in place. Just pulled the clip and it came right out.