Exhaust/intake manifold.

[LRiddle]

Are there different manifolds for the IH and Zenith carbs, or are they interchangeable?

[Barnyard]

They are the same.

[CapeCodCubs]

I thought they were different. The Zenith has a wider throat so the manifold needs to match up? Idk

[Barnyard]

I guess I should clarify my answer. You can use the same manifold as the IH carb for a Zenith, but they did use a different manifold when the Zenith came along from the factory. Many older Cubs are still using the original manifold with Zenith carbs on them.

[JohnMihevic]

I have a 1948 Cub and am using the newer Zenith Carb. and it works great. The throat is a little bigger on the Zenith but it will work on the old manifold. The gasket you need to use with the Zenith Carb on the old manifold is 251235R1 = ABC543.

John M.

P.S. I would like to know if there is any problem using the newer exhaust manifold on the old Cub (will it fit up?) and if it has any increased power advantage since the porting is probably bigger.

[tst]

they are different manifolds, the carb flange is bigger for the zenith and the exhaust pipe size is bigger for the later ones, yes you can bolt the zenith to the early manifold, be careful that the throttle plate does not bind as the hole is slightly smaller in the manifold, to use the late manifold on a early cub you will need a pipe reducer for the exhaust pipe

[LRiddle]

I probably should have been more specific. I have a 51 with an IH carb and I want to make sure any manifold I buy will work. From the answers it sounds like it will.

[Sailor]

I don't remember which carburetor it was but there was a rebuild at Barnyards where the throttle plate was bent because it was making contact with the manifold. The fix was to use two gaskets to provide enough clearance.

[clintmo]

I don't remember which carburetor it was but there was a rebuild at Barnyards where the throttle plate was bent because it was making contact with the manifold. The fix was to use two gaskets to provide enough clearance.

It was a zenith going on a pre-zenith manifold. One of the many new things learned at this Cubfest.

Clint