Y block intake swap

[Y-Blockhead]

'55 and '56 heads had the same sized ports. '57 is when the intake ports got larger in the heads and intake. The ECZ-B '57 intake will still work on a '55 and '56 head. The '54 heads are the ones that are with extra small ports and will not work.

Sal

What Sal said...

 

[dmsfrr]

'55 and '56 heads had the same sized ports. '57 is when the intake ports got larger in the heads and intake. The ECZ-B '57 intake will still work on a '55 and '56 head. The '54 heads are the ones that are with extra small ports and will not work.
Sal

Yes, what Sal said.
Intake to head, the smaller '54 gasket size compared to later gasket...
Also, there is a version of the intake gasket with a smaller hole for the exhaust crossover, it helps prevent paint burn-off on the intake manifold.

 

[KULTULZ]

Knew someone had the exact info on this. Although it will bolt on, you will have a port mis-match with the 55 heads..

Correct. Runner size.