Unpleasant surprise in 50 year old pan!

I don’t have any qualms about it’s accuracy, even if it is off a few degrees it would not make a difference in performance cause the engine can only tolerate so much timing, the tab only shows a number for repeatable reference.
Plus I slotted the balancer to indicate true TDC when setting up for cam degreeing, that’s the mark I use for ignition timing. The factory slot was a few degrees off

 

I believe it is 8* off. Please replace!

 

So I believe that tube is true 0*

 

Maybe your damper had slipped and the other timing tab is close?

 

Should be a groove on the damper that aligns with zero on the tab at TDC.

 

As long as I have all the plugs out now I'm thinkin I may as well pull the valve cover and confirm cam degree with the dial indicator gauge and balancer tape.

 

I believe it’s pretty accurate, but even if it’s off by a few degrees, it’s showing repeatable readings.
Let’s say it’s off by 8* that would put my initial at 10 BTDC and my total at 22*
I know if I were to advance it 8* from where it’s at, the engine would rattle itself to death with over 11.5 to 1 comp ratio

 

It seems all in should be closer to 33 not 22

 

Centrifugal advance stop bushing may be too large.

 

Maybe compare your aftermarket or V6 cover to a stock cover with the cast-in timing tab.
What good is that cover with the bolt on tab if it's not on the money.

 

I’m all in at 30* now.
33* I gotta run race gas at the track
What I’m alluding to is IF the timing tab was off and my timing is ACTUALLY 8* LESS than indicated my total would only be 22*

 

I bought a larger one to limit my centrifugal advance to only 10* so I can run 20 initial, which makes for 30 total.

 

I did the comparison on my two. About 8* but I didn't take a picture to prove it.

 

Mark, how's the cranking when hot?

 

Cranks fine, fast, I attribute that to the overlap in the cam ( which there isn’t much, IIRC 7*)

 

I need the larger bushing since I will have to run total at 28 for the nitrous. That way I can run enough initial for the cam, I think I am at 15-17 initial and a bigger stop would let me keep it there and advance 10-13 more.

 

I checked cam degree today. It's approximately 1.75 degrees advanced. Could be a small part of my detonation problem?

I also noticed secondary flaps and metering rods were not opening completely because secondary pulloff rod wasn't long enough to allow. I bent it a touch to make it longer so flaps open 100% freely.
I also shimmed the secondary hanger up a smidge using a thin piece of plastic secured w silicon and the attaching screw. Experimenting trying to get more secondary fuel supply at wot. Thoughts?

 

Also still wondering ur4 or ur5 plugs back in? This is a ur4 I removed.

 

You will run lean if your fuel pump is weak or filter is partially clogged. Or float level too low. Do your secondary's open all the way? I'm still not sure on your ignition timing. Years ago I could time a distributor by ear. Have lock down bolt just loose enough to barely turn distributor. Turn slowly until engine idle starts slowing down and gets louder or chugs. That is starting to retard. Note location of vacuum can. Turn other way slowly until engine speeds up and start to miss. That is too much initial advance. Note location of vacuum can. Right in the middle would be just right. Some timed with a vacuum gauge. Highest steady vacuum and back off 2 degrees. Works pretty good until you replace your damper.

 

The one UR5 looked better.