[7_Zero]

Thank you all for your responses, I apologize it has taken so long to reply, things have been quite busy and I have not had a chance to work on the car.

Originally Posted by Kurt in NJ

Perhaps it has a larger bore and pistons hitting edges of head gasket, how did old head gasket compare to old one

Originally Posted by Wick

Witch head gasket did you use?

I believe the pistons are .060 as they are stamped 060-C. We used a Best 509 head gasket. The new gasket and old gasket appeared similar in size around the piston side of the engine, but the area by the valves and between cylinders was quite narrow on the new gasket.

Originally Posted by Nosetime

Did you verify piston pop up and gasket clearance? Pull head and check.

I did not verify piston pop up and gasket clearance, unfortunately this never crossed my mind as this is our first head gasket change.

Originally Posted by 1931 flamingo

Disconnect the fan belt and try again, use a long screwdriver or broom stick as a stethascope.
Paul in CT

Unfortunately this made no difference.

Originally Posted by Ernie Vitucci

... Were you able to see that a head gasket failure was the cause of the exhaust in the radiator?...

There was no major blowout in the head gasket, just a couple dark areas. We are thinking that since the previous owners did not drive it much after the rebuild that the head just did not get retorqued.

Originally Posted by Dave N.

I can only offer my life lesson for my engine knock, but raise the distributor up from the new head about an 1/16 to 1/8 of an inch and than tighten it up again.

Raised the distributor and no change, re-seated it, still no change. But it did make a difference on our other car.

Originally Posted by Synchro909

... I stripped the engine and found 0.005" over sized gudgeon pins had been installed. This was done by either reaming or honing the bushes to suit, only they went too far and they were loose, causing the knock. A new set of bushes properly installed all is good now. It may be worth your while checking them....

Any way to check the gudgeon pins without doing a full teardown?

Originally Posted by noyo55

Back about 50 years back I had a similar knock--constant. Turned out a chunk came off the timing gear. It sounded just like a rod knock but was consant.

This is one possibility that we were hoping it would be, but the timing gear looked good. Not saying we did not miss something though.

Here is a link to a couple videos. When running at higher rpms it is harder to hear, there are distinct knocks at the 8-9 second mark and again at 14-15.

We have just acquired a head puller so we can start working on this again.

Thanks!