I always thought the passenger side exhaust manifold looked "different" than the drivers side.   With the two of them side by side they are definitely different.   P/N drivers side ECJ 9431 A, no markings on passenger side

The drivers side "collector" looks larger.  Passenger side looks "rounder" They both fit the engine and the down pipe fine.

Did Ford make different versions of the exhaust manifolds?

They made both the larger size by ‘57.

6 VOLTS/POS. GRD. NW INDIANA

Is this normal for 55?

The smaller, round one for the passenger side is pre-57. Both Tbirds & full-size cars use the same passenger-side manifold. The larger, "square top" manifold for the driver side is 57 Tbird-specific to clear the steering box; it's not interchangeable with full-size cars, but it will fit 55-56 Tbirds. The 57 "Square top" exhaust manifolds do flow better than the earlier manifolds, just as the 57 4-barrel intake manifold flows better than the earlier 55-56 intake manifold for the Holley 4000 "Teapot" carburetor.  

Is the drivers side the same 55 and 57?

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Are the reproduction manifolds any good?  Any fitment or performance issues?

In 57, as noted, the "flat top" manifolds were std equipment -both sides. 

   



54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

It's a 1955 BIRD -

How is the car used?

1) SURVIVOR
2) RESTORATION
3) DRIVER
4) PERFORMER

You want the engine to appear as OEM ASSEMBLY or modified?

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The repops for the bird have been around for quite a while. Haven’t seen any complaints here or elsewhere, so they’re probably ok. Same caution as any other cast manifold about over tightening and breaking an ear off.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ