318 intake manifold fit on a 273?

[Coryduran]

I remember reading somewhere someone mentioning that if an intake manifold fits on a 318, it'll fit onto a 273, is this true in general? I only ask because I can't seem to find any aftermarket intakes that fit a 273 with a single carb four barrel square bore.

Thanks in advance I'm sure I'll get 50 answers, all different

 

[yellow68runner]

If I'm not mistaken,only 66 and later 273 will accept a 318 intake :read2:

 

[cleverbob]

The early 273 used a smaller head bolt and, this is the problem "a different bolt angle." You can open the manifold mounting holes to allow for the angle but the bolt head does not fit flush. I use 66 and later heads drilled and tapped to accept the normal 3/8 manifold bolts.

Now that I think of it I did use a 1965, 273 4bbl manifold on 66 heads, [after drilling out the mounting holes] for a couple of years and never worried about the miss match of the bolt heads. Just information not a recommendation.

 

[65Vart]

You should pull a valve cover off and get the casting number on those heads. That will tell you what you are dealing with. You can also check your manifold bolts. If they are 5/16 you have the early 64/65 heads with the strange bolt angle. If they are 3/8 you have the later ones that will accept a later 273/318 intake. If you have the early heads try and look for an eldlbrock D4B intake. I found mine on Ebay, they show up sometimes.

 

['64 Cuda]

I also recommend that you look for a D4B. If you can't find one, I have an Offenhauser 360 Equa-Flo single plane manifold for the early heads that I could probably be talked into selling.