 After the baseline tests,...  After the baseline tests, we took the fastback to Fantasy Muffler in Buena Park, California. Here, the car is on the lift and ready for a look underneath. We must disconnect the pipes from the manifolds before they can be removed. |  There's plenty of clearance...  There's plenty of clearance between the small-block exhaust manifolds and the shock tower, as this car was designed to accommodate the much larger 390 engine. |  Underneath the Mustang, the...  Underneath the Mustang, the project began by cutting the header pipe on both sides of the engine. Next, they were disconnected at the exhaust manifolds and then removed from the car. |
 This under-the-car view of...  This under-the-car view of the left manifold shows the tight quarters the exhaust pipe must negotiate. When the cross shaft for a manual clutch linkage is added here, things become even more complicated. |  On the right side of the car...  On the right side of the car we can see that clearance is a little better. The starter and the automatic transmission dipstick tube are two heat-sensitive areas to consider. Transmission cooling lines are also a factor. |  With the header pipes disconnected...  With the header pipes disconnected at the bottom, it's simple to remove the manifold from the top. |
 All spark-plug wires must...  All spark-plug wires must be disconnected and moved out of the way before the manifolds can be removed. Although it is not mandatory, you might remove the spark plugs, as it is easy to damage the ceramic insulator with the manifold or header flange. |  With the log manifolds off...  With the log manifolds off the engine, it's interesting to compare the two castings. Although the K-manifolds seem to have smoother contours and slightly longer runners, the ports and exhaust openings are the same sizes. |  Installing the K-code manifolds...  Installing the K-code manifolds is easy because they can be installed through the top and attached to the cylinder head with little difficulty. The K-code casting sometimes requires different attaching hardware. |