[HWYSTR455]

One of the punch list items I needed to address was a tip-in det issue. I worked the timing table again and again, and couldn't seem to get rid of it. Long story short, went back to square one, did all the initial & running timing checks, and found there was timing creep at tip in and above 3000 RPM. To correct, inductive delay settings needed to be adjusted.

In adjusting that, I found that changing the value had no effect on the creep, so replaced the whole ignition system, new coil, new dizzy, new CD box, wires, plugs, and went over the whole ignition portion of the harness. That did it, was now able to get response from the inductive delay setting.

In testing the second time, to view the timing marks better, I pulled the air intake tube off, which helped considerably. With the tube off, I now was hearing a 'pop' back into the intake plenum. Went over the lash adjustments multiple times, and couldn't resolve it.

Broke out the bore scope, and tried to fish it down there thinking maybe something found it's way into the intake tract and boogered a valve. Was not able to see very well, so pulled the intake. Still no go with the bore scope, all the intake valves looked good. Made sense, since the 'pop' was blowing back into the intake tract, so I started to fill the cyls with compressed air.

And, air, with all the rockers off, was leaking into the exhaust crossover, indicating a head gasket issue.

Pulled the head and found this:

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