Review on Replacement Inserts Compatible CAL389 100 Engines by Chris Cruz

inserts exactly as described. I've used them on two engines for a total of 18 uses. One is currently being renovated to ensure we don't have any issues. As you can see from the photos, Ford did a terrible job with the number of threads holding the spark plugs to the head. These inserts increase the thread depth on the spark plug and in the head itself. These inserts require a significant amount of labor to install but are well worth it. I have no problem reusing them.