I talked to the former owner of my '98 Stang 'Vert last night as we are pretty good friends. He mentioned to me that he had a problem about a year after he purchased the 'Stang (new) and had taken it back to the dealership where he stated the heads and manifold were replaced on the car.
He isn't as informed as we are as to what NPI and PI heads are so he wouldn't know if there is some chance that any PI heads could have been installed. He always insists that this was a very late '98 model and that there had been a subtle change on it vs. early '98s, but I have still yet to hear of anything to validate that particular claim.
What I do know is this: My motor pings something fierce on regular octane fuel (which I only ran once). It's much better on mid-premium grade fuel and I always rotate the Mid and Premium octane fuel at half full tank. This brings me now to my question: Is there a way to identify PI vs NPI heads externally without having to remove them?
He isn't as informed as we are as to what NPI and PI heads are so he wouldn't know if there is some chance that any PI heads could have been installed. He always insists that this was a very late '98 model and that there had been a subtle change on it vs. early '98s, but I have still yet to hear of anything to validate that particular claim.
What I do know is this: My motor pings something fierce on regular octane fuel (which I only ran once). It's much better on mid-premium grade fuel and I always rotate the Mid and Premium octane fuel at half full tank. This brings me now to my question: Is there a way to identify PI vs NPI heads externally without having to remove them?