Pre-HO Exhaust Manifold

89 4.0 with cracked manifold. I was led to believe that the Banks HO (91+) header will fit the pre-HO motor, the only difference being the O2 sensor bung, which can be plugged.

Just recieved the header and there is no O2 bung. Before tearing into this, have I been misled? Will this header work on the pre-HO motor?

non HOs have the bung and HOs don't. I don't know if it will bolt up but if it does I think you can weld a bung on.

The pre HO manifold has the O2 sensor in the manifold. The HO manifold has it in the down pipe. The down pipes are different. The HO manifold should bolt up but you will need to have a new down pipe made or bought with the o2 bung in it.

The EGR will also be lost.

Michael

It might be that the Borla header has the EGR bung. Clifford and Pace Setter do. On the Clifford, its not advertised as for the Renix, but it does have a bung. The tube will need drilled out to complete the system.
Tom