Manifold confusion

[celticsam]

I have an 85 Cutlass Salon, 307. The heads are stamped 7A, which are...correct me if I'm wrong...the small "swirl" port heads. My manifold is stamped A4. I thought the A4 manifolds only came on the 5A heads. Is this the same manifold? Would the ports match the 69, 5 headed 350 that is going into the car? I was going to buy a Performer, but if its a properly sized A4, I'll keep that. After all, the 350 was a 2bbl engine, and I'm not changing cams or anything...

 

[olds307 and 403]

It should, you will know when you pull it, should be a big difference in port size. Are the 7 and the A, the same size? Weird someone would swap intakes on a swirl port 307. Maybe they stripped a fitting and thought all 307's were the same intake wise.

 

[69hurstolds]

The A4 can be used on the 350 without issues if you like. The A5 should have been matched with those 7A heads. I agree it must've been one of those Olds V8 is an Olds V8- it bolted on so it has to work type of approach.

 

[Minion1186]

No big benefit to buy a performer compared to the A-4, both aluminum, both flow about the same and weigh about the same, difference is you can trip over one at the yards or pay $200-$300 for a name on the other.

 

[celticsam]

Just very odd...this car was bought from the original owner who was anything but a car enthusiast, and looks to have been totally untouched (and poorly serviced). It has the AIR injection ports in the heads but the A4 is clearly on the manifold. Its a bonus to me...but a mystery as well. I guess it would be to much to wish for to hope the exhaust manifolds would be large port as well....(they are not the tubular style...)

 

[olds307 and 403]

If they are cast iron, they are large port. Unless you have a very early model 85 where they were using up early 307 parts, which I doubt, check the block casting # above the water pump. Something is strange here.