[Terry Crist]

First, lets figure out what and where the knock is from. Might be able to save you a lot of work.

What does the "knock" sound like? Is it tinny or a solid sound.

Can you tell approximatly where it is knocking from (front of engine, rear of engine, top/bottom)?

Does it knock all of the time or just under acceleration?

How many miles are on it?

Does it run fine other than the knock.

Does it use any oil?

My mom had an El Camino with a SB350. It developed a knock and not knowing much at he time, I just replaced it. I used all of the old sheet metal stuff on the new engine and got it running great.

Then I started inspecting the old engine and found that one of the nylon teeth off of the cam timing gear had come off of the gear and stuck in the timing chain. Thus resulting in the timing chain connecting with the timing chain cover.

Long story short, it could have been a fairly easy fix.