Any small block intake should work 260-330-350-403. Some of the earlier ones might not have some of the fitting you need.

 

260 motors have unique (miniscule) ports and thus uses a unique intake. While the intakes from other SBOs will bolt up, the flow disruption from that port mismatch will reduce power below that of the stock DualJet intake. I don't even think an A5 has small enough ports.

 

This was going to be my suggestion. I thought they were the same size? Apparently not.

Good luck finding one. Usually the first thing to make it to the scrap pile if not the whole engine.

 

I have 2 of these intakes if you are still interested. Both were taken off of running cars about 2006 and have been in my basement since then. The red/blue one was taken out of a 1978 442. Whole engine compartment was painted red. Don't know why. The other came out of a 1979 Cutlass Calais.

 

I can take more pictures if needed. PM me.
Phil

 

I have an a4 from a 84 h/o if you wanted to go 4bbl. ports are pretty small.

 

 

These are both the same manifolds. Why do you assume the 442 one is wrong? In 1978 the base engine for the 442 was a 231 and option for 260 or 305. That manifold is definitely not for a 305
Maybe you missed this tag in the picture

 

 

Both intakes were removed from Olds 260 V8 engines. The 1978 442 could only get 1 of 3 engines- Buick 231 V6 2bbl, Olds 260 V8 2bbl, and a Chevy 305 V8 2bbl or 4bbl. I parted out a 1978 442 that had the 260. The car ran but was in sad shape. Probably could have been restored if I wanted to spend many thousands of dollars, but it wasn't worth it.
Both intakes have the casting # 558916 and have a large A1 on the front left area next to the thermostat housing.

 

 

 

And yet, STILL too big for the 260. Go back and read post #3 again.

 

Someone sell him an intake for a 350 with the rest of the 350 bolted to it.

 

 

 

78Cutlass4Speed has what you are looking for, the legendary alum manifold, looks to be a good one without any helicoiled threads anywhere which in and of itself is worth the price of admission.