Do you still have the rare, smaller diameter stainless, unique to the 260 crossover pipe, highly valuable from the ultimate performance package from the late 70's. I also have one of those sets of 78 260 manifolds. The pervious bent 1 3/4" dual exhaust without tail pipes for my 70S. I also have 307 manifolds that came with my 73 350. Someone screwed a bolt into where the O2 sensor was. I wonder if it was the proper metric thread.I have one from a 1978 Olds 260. If you think it may work for your application, let me know.
Actually my AIR pipes were into the exhausts manifolds, I had to cap the all as removed the air pump and hardware and got rid of feedback carb for an older non feedback carb and changed distributor so no computer needed. I probably don't need the O2 sensor either. My car was made for Canadian market maybe thats why AIR pipes were put in exhausts manifold. But will try to locate one of those manifolds.They may physically bolt on to the head, but if they're right for your application, you need to consider that. Not every RH Olds exhaust manifold is the same.
No Olds exh manifold I'm aware of has the AIR holes. That was done in the heads. 1985 is the last year they used cast iron exh manifolds to my knowledge anyway. If you're car is stock, you will need the one with the O2 sensor hole.
Last good part number for RH was 22521449. Previously 22506300. These are WITH the O2 sensor hole. In fact, the 449 has an extra hole plug on the top of the tail hump for some friggin' reason. Maybe another application to move the O2 sensor to the top? I dunno.
22506246 is an older number as well, no sensor O2 hole. Here's an old school one without the O2 sensor hole, but requires the same donut seal and 3 flange cat converter bolts/springs as the later ones. p/n 417754. Only difference between what your car needs and this one is the lack of O2 sensor hole.
<p>Selling a used manifold. No cracks. Has some surface rust. Make sure it will fit your vehicle before purchasing. </p><br><br><p>Oldsmobile Rh Exhaust Manifold 417754 Toronado Cutlass 442 F-85 Vista Cruiser. Condition is "Used".</p>www.ebay.com
I might do that than trying to find an older factory manifold I don't need AIR holes as I removed all smog equipment and changed carb and distributor so no more computer junk.Check out Thornton JR 350 exhaust manifolds...manifolds for both sides and eliminate the crossover pipe...more power...sounds better...$349 and a day at your local muffler shop...spray everything down with PB Blaster a few times
Got any pics of said manifolds with the AIR piping plugs? I cannot for the life of me see why they would forego the holes in the heads for holes in the exhaust manifolds. Absolutely no difference.Actually my AIR pipes were into the exhausts manifolds, I had to cap the all as removed the air pump and hardware and got rid of feedback carb for an older non feedback carb and changed distributor so no computer needed. I probably don't need the O2 sensor either. My car was made for Canadian market maybe thats why AIR pipes were put in exhausts manifold. But will try to locate one of those manifolds.
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