An attempt to pay back for all the help.

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spinman_1949

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In a attempt to offer feedback re all the excellent help I received from many members re the ping thread, I am going to see if I can share what I learned.

I bought a brand new distributor and took it apart. I wll be posting pictures.

Thx to infor I found from crackeback I now know that the distriutor I have as well as the one that is in the car has 15 degrees 30 degrees crank mechanical advance available. My digital mic shows the slot in the advance plate to be .475 inches which is 15 degrees.

So now I need to go through the process. Yup gonna use a piston stop to identify the true TDC. Make sure the harmonic is not slipping. Omce that is done I will create a degree tape. Then tune to best idle based on vacuum. Drop back 1 inch. Again thx crackedback. So now the big question. I know that a supposed expert tunner set the initial to 22 BTDC. Now yes is the mark on the damper accurate. So for now lets assiume it is. So if 22 BTDC is the target for a good idle with this cam, then it does not take a rocket scientist to figue that a diss that provide 30 degrees mechanical is going to result is some major PING, if not outright detonation.

So once I establish the correct initial based on the vacuum approach I will then modify my new distributor to offer no more than 36 degrees total advance mechanical.

So once again the chart crackedback comes to the rescue. If I have 22 initial and I need 36 total, then I need 7 degrees at the distributor. And that is a slot reduced to .355 inches.

Just starting to learn.
 
I think trailbeast got in there with some input as well.

Just make sure the car will start when hot with 22* initial. If it drags the starter real hard or kicks back, you need to dial back the timing a bit. You could use the old distributor to test it out. If you know that it had 22*, then run with it there as it's plenty of initial and anything more may not be of great return. The vacuum method works well to find what the engine wants, that's for sure.

The hillbilly timing tape deal works great. I never buy timing tapes anymore.

One thing that I found interesting regarding initial timing suggestions and where to run it. Even MSD says run as much initial advance as you can now.

Sounds like you have a good plan, verify TDC mark on the balancer to your cover and make it happen.

Any time on the help. Hope you got the transmission deal figured out.

Good luck with it.
 
Crackedback,

No dispresprect intended to others who had input. I mentioned you because of the links I found in different threads from you re timing. As I said many members had good input. As far as the tranny? LOL that one is easy. Arm lost washer and I would assume cotter pin to gear selection rod. In the world of mechanics, that one is eqivalent to an oil change.
 
Yep, lots of good people here. We all have varying approaches as there are plenty of ways to skin a cat.

Good to read the trans fix was a simple one.
 
so how big is the slot?i made mine 5/16 and it was 20 initial and 36 total.....afterward
 
Bad440,

Here is the portion of the article that crackedback posted on another thread.

This is from a magazine article a while back.
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dist. degrees X 2 + initial= total


dist. degrees / slot length
6.............. .340
7............... .355
8............... .375
9............... .390
10.............. .405
11.5 ........... .420
12.............. .435
13.............. .445
14.............. .460
15.............. .475
16.............. .490
17.............. .505
18.............. .520


So you say your slot is 5/16 OK that is 5 X .0625 = .3125 Not on the chart, but should be around 5 degees 10 total at the crank. So either the chart is wrong or your slot is closer to 3/8 in length. That would give you 8 degrees 16 at the crank plus your 20 initial = 36

I am not sure as to the source of the article, so I can not verify how accurate the chart is. But there is a faily large variance when comparing what you have as it relates to the chart.

When I manually move the unit with the springs detached it does appear that it is moving about 15 degrees. Now I know it is hard to identify this by sight of course. What I may do is create a simple jig with a degree dial. Then I can compare my findings to the chart.

I will take pictures of everything and post here.

Should prove interesting.
 
That chart is the same info I have and several people have commented on other boards that it seems to be within reason for accuracy
 
Another hillbilly thing to do.

Center a protractor over the rotor and line it up. Then twist the rotor and observe degrees. Easier with an extra set of hands. I've done that with a protractor and sometimes a degree wheel and a zip tie taped to the rotor. Neat thing about the degree wheel is sometimes you can put the degree wheel down before the rotor goes on.
 
Crackedback,

I have downloaded a 6 inch diameter degree wheel which I will print. Then I will paste it on a plastic disc and drill a hole to take the shaft from the diss and then use locating pins to told the advance plate at 0 degrees.

One thing I have noticed. I do not think advance is entirely linear. I see at the end of the throw an increase in advance. I saw on one white paper a picture showing slots at a slight angel from the shaft. Another showed the slots at a true 90 degrees to the shaft.

I hope to confirn the advance offered per each 1/32 of movement.
 
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