Timing chain catastrophe.

Well, out playing with the Mustang today, the timing chain broke at about 5000 rpm.

This is a stock bottom 72 460 with factory dish pistons, C8VE heads, with slightly larger than stock valves. Also using a very small Edelbrock Performer hydraulic cam, something like .480 lift and 200 duration at .050.

What are the odds that I DIDN'T bend valves? I am hoping that with this little cam and dished pistons, maybe they didn't kiss? Am I just dreaming?

I don't know but I had one turn loose at 5000 in a stock 70 302 with a stock cam and it bent 2 intake valves. It had the original chain in it. I have never touched another engine without replacing the chain with a quality one.

fordguy69 wrote:



What are the odds that I DIDN'T bend valves?

I would say about as good as winning the lotto.

Most likely have some valve/pushrod damage, but getting to the root cause of the chain failure would be my #1 priority.

Was this a fresh engine or does it have some time on it?

It's got some time on it. It's an old engine I had lying around from another car and threw it together just to get all the bugs sorted out on the car before I put a good motor in it. Guess my timeline just got accelerated.

fordguy69 wrote:It's got some time on it. It's an old engine I had lying around from another car and threw it together just to get all the bugs sorted out on the car before I put a good motor in it. Guess my timeline just got accelerated.

If it was the factory chain the nylon top gear more than likely went bye bye

Wheelie58 wrote:Most likely have some valve/pushrod damage, but getting to the root cause of the chain failure would be my #1 priority.

X2