To much advace on the lever

Brendan1959

Brendan1959

Member
Hi
I have a 31 Five window, I marked top dead centre using the pin and checking the piston was TDC. Then calculated 25 degrees, and marked that.


I find that about 25 degrees advance is about 1/3 of the levers full travel, so if I pull it to far I get way to much advance. I was thinking of making a stop for the lever, has anyone done this, or is there a way to adjust maximum advance?
Brendan
 
Is there a reason your calculating this? Set the rotor correctly when the pin drops in the cover and drive it. Theres a pic someone posted the correct rotor position.
 
You can tell where your advance needs to be by holding a steady speed and moving the lever. You’ll feel the engine languish,when it’s to retarded and where there’s no more difference in power at the upper end.(advanced)
 
I am ok with the setting of the advance by ear or feel.
I would like to allow others to drive it and not to have to worry about the setting, it seems to have the ability to get to 60deg or more which seems a lot, this is my first left hand drive A, my right hand drive did not have this much on the lever before I put in a mech advance ford prefect distributer.
Brendan
 
I have made a stop. I have a 6.0 head so my reason is different for the stop than yours.

I took a small piece of aluminum flat stock about 3/4" wide and folded it over. Then drilled and tapped and installed a set screw. Then placed the folded over aluminum (u shaped) and slipped it over the quadrant.
 
Re: Too much advance on the lever-if you have 59 degrees advance READ THIS

Brendan1959 said:
I am ok with the setting of the advance by ear or feel.
I would like to allow others to drive it and not to have to worry about the setting, it seems to have the ability to get to 60deg or more which seems a lot, this is my first left hand drive A, my right hand drive did not have this much on the lever before I put in a mech advance ford prefect distributer.
Brendan
Click to expand...


IF YOU ARE GETTING 59 DEGREES at full advance then you have a Model B timing cover installed and that much advance will damage engine.

You need to get a Model A timing cover.


One problem with using Model B timing cover with Model A dist is that if done this way you will have 59 degrees advance with lever all the way down.

19 degrees advance from Model B Timing cover.

added to 40 degrees from Model A dist is 59 degrees ... WAY TOO much.

THis is why engine bucks and F@4ts with lever totally advanced.

An otherwise stock Model A engine with a 5.5 or 6.0 head should be run with 28 degrees advance to prevent engine damage.

Full advance on correctly setup STOCK dist is 40 degrees with lever all the way down.

Therefore 28 is about 3/4 on the quadrant ...

Just because it goes to 40 does not mean that the lever should be run that way
 
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I made a stop at 28* because I have a 6:1 head. Later I read that with a 5.5:1 head it should be max of 23* and with a 6:1 it should be max 21*. So now I don't know what is best, but I normally set it by feel (like Chuck Sea Tac )and the 28* stop limits it to 28*.
 
OK, I have just ordered a dial back timing light, I should then be able to work out where the recommended max advance is in the quadrant, then fit a stop like old31.
I assume it is a stock head, does anyone know off the top of your head (no pun intended) expected compression psi? My roadster has a 6.1 head so it should be somewhat less than that I suppose.
Brendan
 
Stock maximum spark advance on a Model "A" is 40 degrees at the crankshaft and 20 degrees at the distributor. The Model "B" has 9-1/2 degrees more than the Model "A."
 
Mixing Apples and Oranges does not change the facts.

Mixing crankshaft degrees and camshaft degrees does not change the facts it just gives wrong answer.


The timing pin hole in the Model B cover corresponds to 19 crankshaft degrees

which is (9-1/2 camshaft degrees) BTDC on the number one piston.


40 crankshaft degrees plus 19 crankshaft degrees still equals 59 crankshaft degrees!
 
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My stock A runs well at 28-30 degrees advance. I got a timing tape from Bratton's and I time it with a timing light so when the lever is all the way down, advanced, it is at 30*BTDC. Then I don't have to worry about too much advance or if someone else ever drives the car. Ha not likely.
 
" Later I read that with a 5.5:1 head it should be max of 23* and with a 6:1 it should be max 21*."

How crazy is this? Everyone knows a Model A max timing should be 28*-32*
 
Brendan 1959. Why fool with making a stop for the lever when you can just retime the engine for 30* with the lever all the way down. You said you are getting a timing light so it will be easy to do and you don't ever have to be worried about too much advance.
 
I always thought that with a 6.0 head you should not go above 21 degrees. Is this not correct.

Even with a dialback you need to put a stop on the quadrant. I have timed mine for 2 degrees at startup and stopped it at 21 degrees. If I timed mine to be at O at startup I still need to move the stopper on the quadrant somewhere to be at 21 degrees.

If Brendan times it for the lever to be all the way down, then where in the heck would his startup degrees be?
 
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If he times it for 30* BTDC with the lever all the way down then all the way up, retarded, would be 10* ATDC. Just fine for starting.
 
"I always thought that with a 6.0 head you should not go above 21 degrees."

where did you get that from?
we are running some 6.0 heads at 35*, car goes like h*ll
 
Stop is made this is about 28 deg.
 

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