Does anyone know of a source for exhaust manifolds for a '49 303 V8? I've not been able to find any in my searching.

 

I know I have some 324 manifolds. I'll look and see if I have the ones from a couple of 303's I've dismantled over the years.
John

 

As it turns out, my engine has 371 heads on it, so I need manifolds for a 371.

 

Can you share what the two digit number is cast into the heads? It would be over one of the two center ports. That would help idenitify what year of 371 heads they are. Then do you have exhaust already in the car that you are trying to match up to? Or are you just trying to match the ports on the heads?

 

I didn't think 371 heads would work on a 303. Charlie Jones will know.

 

Any 1st generation (49 thru 64) Olds head will bolt on to any 49 thru 64 block.
However, intake ports may not match up well, or not at all
303 and 324 engines were low deck blocks so they need to have intake manifolds for 303 or 324.
No matter what head they had. Hence the potential for port mis match.
When the engine was enlarged to 371 in 1957 the deck height was raised.
The deck remained the same for 1958, so all 57 or 58 blocks must use a 57 or 58 manifold including the famous J-2 triple carb manifold.
In 1959 the deck height was raised again for all 371 and 394 engines. all 59 thru 64 371 and 394 blocks must use a 59 thru 64 manifold.

To the OP. Please post a couple of pics of the heads and block and we may be able to tell you more about what parts your engine has.

 

Aren't 303 manifolds round ports and the rest are all square ports? They can be matched (ported to match) but a major job. I always thought because of the deck height difference intake manifolds for the 371 were wider and couldn't be swapped without machine work on the smaller engines, but the exhaust manifolds would work without changing anything. The difference would be where the exhaust matched up to the muffler pipe, usually not an issue in a hot rod but could be on a stock set up. This is from my memory of a half century ago, could all be wrong... Tedd

 

Took a pair of factory exhaust manifolds off the 371 (14) heads I am building if you are interested.

 

Here are some photos the shop sent:

 

That number stamped on the block signifies that it is a 1950 303 block. With a Hydra Matic trans.
The heads are 1957 (#14) and 1958 (#16)