Re: The hits keep coming. Loud tick from the 454
What kind of fuel pump do you have?
You say it is coming from the front of the engine - could be fuel pump pushrod.
I recently had a problem with the Holley 12-454-11 pumps. I tried 3 pumps, all made a very similar noise. I discovered that they have cast the engine block housings on them 1/4" too thick without changing the pump arm, which causes the pump arm geometry to be off and it makes the same tapping noise. The problem is the pivot point of the arm is now 1/4" farther from the block, and the pump arm sits about 1/4" farther out because they didn't change the pump arm to match, so the pushrod is now too short.
I took detailed measurements of all 3 Holley pumps, plus 2 stock pumps (no noise) and a Carter m4889 (no noise) and this was definitely the problem. My solution was the Carter m4889.
I've contacted Holley about it and even returned pumps and information and they are looking into the issue. But it's very very clear they have a manufacturing problem with them. Many people use them ok (don't know how) but in my case, it was a very clear problem.
So, check your fuel pump.
1972 Chevelle, 454, 200-4r non-lockup, 12 bolt 3.73
1981 Camaro Z28, 355, TH350, 3.73