1990 Ford Mustang Head Swap - Back In Business

Reducers are used on all of the studs and must be covered with moly-lube.

Once again, use moly-lube on the threads.

With the heads torqued into place it was time to measure the pushrod length. It required the installation of a rocker arm and an adjustable pushrod checker. Once the desired height was found, we checked all the intake and exhaust rocker arms and pushrods. We measured the pushrod length to be 6.350 inches using a pair of calipers.

With the heads torqued into place it was time to measure the pushrod length. It required the installation of a rocker arm and an adjustable pushrod checker. Once the desired height was found, we checked all the intake and exhaust rocker arms and pushrods. We measured the pushrod length to be 6.350 inches using a pair of calipers.

Once the correct pushrods were slid into place, the Pro Magnum rocker arms were oiled and bolted down. We used washers under the rocker arm studs to help the thread engagement on the poly-lock.

Once the correct pushrods were slid into place, the Pro Magnum rocker arms were oiled and bolted down. We used washers under the rocker arm studs to help the thread engagement on the poly-lock.

The Fel-Pro intake gaskets were trimmed and laid on to the intake side of the RHS heads.

The intake is lowered into place and the injector harness and fuel rails are reattached.

Eric Holliday uses a flashlight to check each port to make sure it lines up with the cylinder head. He is also making sure the intake gasket is not protruding in the intake port. "Intake gasket alignment is critical in regards to restricting airflow," Burcham says.

Phil Watson uses the stock valve covers with the double-thick gaskets to help clear the rocker arms. This worked just fine in our application. Holliday torques down the intake manifold to 20 ft-lb, but he first started at 10 ft-lb. Begin in the middle and use a criss-cross pattern.

The water-coolant temperature sensor is screwed into place.

Watson bolts the upper intake manifold back on.

Autolite 3924 spark plugs or equivalent are required with these cylinder heads. We gapped them to 0.042 inch.

The spark plugs are installed, the distributor reinstalled, and the spark plug wires attached to the spark plugs. Timing was set at 15 degrees for all testing.