Pinging on acceleration.

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Looking at the pic in post #17, to me, it seems:
- the yellow arrow is pointing at the 35* mark. Spacing between the white marks look to be correct on that diam dampener for about 10* increments between marks.
- the 0* [ TDC ] mark is the lowest mark in the pic. You can see the distinctive slot in the pulley edge that extends to the rear edge of the pulley.
 
Look REAL close on the balancer where the arrow is pointing. There's a hash mark. I'm almost positive that's the correct mark. If the balancer has been replaced, it will have two marks. All of them I have seen do. One mark for each timing tab position. Of course he won't know for sure which is correct until he checks TDC as he's been told. If he'll do it. You know how that goes around here.

Yes. I'll be doing it. I got caught up at work the past couple of days.
 
Got to play around with the timing today. With timing set at top dead center on the yellow mark it runs at a much lower RPM and seems more responsive. The only problem is, it's a tooth off. I'll pull the distributor cover off and for example, it's a 6 o'clock. I try and get it to 5 o'clock, but it snaps to 4 o'clock. It's either like the picture below to get it set to 0 degrees, or I have to bury the tab in the block and it's like 15 degrees past TDC. I have my daughters concert tonight, so I'll try tackling it again tomorrow.

IMG20241009172241.jpg
 
Okay, figured out the problem. It boils down to... I'm an idiot. I didn't realize there was a second bolt on the bottom of the clamp plate that went into the distributor that allows it quite a bit of adjustment. So, my struggle with my own incompetence is just getting started.

1728607313828.png
 
Get you a Snap On S9467B distributor wrench. That will enable you to get to the top and bottom fasteners easily. They're gettin kinda hard to find now.
 
Okay, figured out the problem. It boils down to... I'm an idiot. I didn't realize there was a second bolt on the bottom of the clamp plate that went into the distributor that allows it quite a bit of adjustment. So, my struggle with my own incompetence is just getting started.

View attachment 1716314032
You're not incompetent, an incompetent would still be at a loss w/o seeking the answer/solution or start doing hack things, lots of folks are unaware of the second adjustment slot. You've got it, but DO make sure the mech.adv operates freely, it should turn easily with thumb & finger to it's stop & snap back when released. The OE lube drys/cooks & gets gummy lots of times, just free'd up one on the '72 Satellite 383 I rebuilt the carb on ~a year and a half ago.
 
Pulled spark plug for cylinder 1 and checked TDC. The yellow mark is dead in the middle of the dwell as far as I can tell. Time to hunt for a distributor wrench for this thing.
 
Remember back in the 60’s regular gas was 95 octane .
So today you should be using premium 93 octane and setting the timing for it .

Leaded gas was for valve seat wear , today you have two choices , run hardened valve seats or a gas additive with every tank .

Also you have two choices when it comes to motor oil to keep your non roller cam and lifters alive , run hot rod motor oil that has ZDDP in it or add ZDDP to modern oil with every oil change .
 
Remember back in the 60’s regular gas was 95 octane .
So today you should be using premium 93 octane and setting the timing for it .

Leaded gas was for valve seat wear , today you have two choices , run hardened valve seats or a gas additive with every tank .

Also you have two choices when it comes to motor oil to keep your non roller cam and lifters alive , run hot rod motor oil that has ZDDP in it or add ZDDP to modern oil with every oil change .
This is a slant 6. They blueprint down into the 7s for compression. 93 is a total waste on them.
 
I may just buy me a long 7/16 box wrench, heat it up and bend it until I can find an appropriate tool. I see they pop up on eBay once in a while.
 
I may just buy me a long 7/16 box wrench, heat it up and bend it until I can find an appropriate tool. I see they pop up on eBay once in a while.
You can certainly do that. Just remember, when you get on the bottom bolt from the top, you now turn it clockwise to loosen as viewed from the top.
 
Pulled spark plug for cylinder 1 and checked TDC. The yellow mark is dead in the middle of the dwell as far as I can tell. Time to hunt for a distributor wrench for this thing.
I'm not sure if this was mentioned. As you've found real TDC, did that align with tdc mark on the balancer? The balancer can slip when it's old and then the mark is totally unreliable.
 
I'm not sure if this was mentioned. As you've found real TDC, did that align with tdc mark on the balancer? The balancer can slip when it's old and then the mark is totally unreliable.
The yellow mark is where TDC for piston 1 is. I'm presuming that's the correct one as it looks like there's a mark on both sides of the balancer. Problem is now, I've got it timed to 0 degrees and it falls on it's face when punching the gas from idle. Revs fine if I start it at maybe a grand, but practically dies otherwise.

While searching the forum, I found you're supposed to remove the compression ring from the spark plugs, which I had not. I've ordered some new tube gaskets since I think they're leaking. I'll check the tubes to make sure I didn't damage anything, remove the rings from the spark plugs and check the timing again.
 
The yellow mark is where TDC for piston 1 is. I'm presuming that's the correct one as it looks like there's a mark on both sides of the balancer. Problem is now, I've got it timed to 0 degrees and it falls on it's face when punching the gas from idle. Revs fine if I start it at maybe a grand, but practically dies otherwise.

While searching the forum, I found you're supposed to remove the compression ring from the spark plugs, which I had not. I've ordered some new tube gaskets since I think they're leaking. I'll check the tubes to make sure I didn't damage anything, remove the rings from the spark plugs and check the timing again.
Well of course it will fall on its face. You've been told time and again 0 degrees is nowhere near enough initial advance. What does it take to get through? Pull it up to 10 degrees and enjoy it.
 
Guess I must have missed it. Will do.
Post 4 and 26 elude to it. Zero degrees will get you nowhere. I had my stone stock 170 at 12 initial. I tried 15, but that was a tad too much. It ran a little rough.
 
Remember back in the 60’s regular gas was 95 octane .

No, in the '60s regular gas was 91 octane, by the RON method (Research Octane Number).

Other parts of the world still post RON on the pumps, but since the '70s in North America, we use the AKI method (Antiknock index), which is the average of the RON and the always-lower MON, Motor Octane Number. Today's 87-octane regular has a RON of ~91. That is: the same antiknock performance as the pre-1970s regular gasoline labelled "91".

So today you should be using premium 93 octane and setting the timing for it .

No, a stock or near-stock Slant-6 runs well on regular (87, by today's numbers). There is no benefit to running high-test gasoline in a stockish Slant-6, but there is also no drawback—except to the wallet. High-test doesn't burn slower, it just more strongly resists spontaneous combustion (detonation, ping, knock…). Higher-than-87-octane gasoline is a waste of money. Yes, you can tune the engine with some more advance and get a bit better fuel economy if you run high-test, but the math doesn't come close to working; you still wind up spending a lot more than you save.

Leaded gas was for valve seat wear

Primarily it was a cheap way of raising the octane of gasoline. It also buffered the exhaust valve/seat junction, so automakers didn't have to harden the seats or specify higher-grade valves, thus saving them money.

today you have two choices , run hardened valve seats or a gas additive with every tank .

The Slant-6's exhaust valves are small, and the seats well-cooled. A pre-1973 Slant-6 (no hardened seats) in typical service will last a good, long time before there's any valve seat recession; when that eventually does happen, that's when you have hardened seats put in. Additives of this claimed nature are a waste of money twice: first when you buy them, and then when they crud up your spark plugs a whole lot faster in exchange for no practical benefit.

Also you have two choices when it comes to motor oil to keep your non roller cam and lifters alive , run hot rod motor oil that has ZDDP in it or add ZDDP to modern oil with every oil change .

This is also false. Yes, really.
 
Pull it up to 10 degrees and enjoy it.

10° is overly much—it'll throw the carburetor idle adjustments too far out of whack. It'll also foment pinging on acceleration, which was kind of the start of this thread. 5° is a better starting point, with the goal of winding up somewhere between 2.5° (the spec setting for the good-running pre-smog 225s of the '60s) and 6°.
 
10° is overly much—it'll throw the carburetor idle adjustments too far out of whack. It'll also foment pinging on acceleration, which was kind of the start of this thread. 5° is a better starting point, with the goal of winding up somewhere between 2.5° (the spec setting for the good-running pre-smog 225s of the '60s) and 6°.
My 170 ran best at 12. And that was with a brandy new timing set so it wasn't retarded from being sloppy. Basically what I was trying to tell him is just experiment around with it and see. That's the only way he's gonna learn.
 
I don't doubt you. And some of the later '70s smogger motors called for a big whack of initial timing. OP's got a 225, tho, made before then. That's what my 5ish-degrees recommendation was meant for.
I unnerstand. I run 21 initial on Vixen's 225, but she's pretty heavily modified and I have the total limited to 30 degrees. She runs way stronger than an inline six has a right to. We probably put over 100 miles on her today.
 
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