Timing marks on 8ba

C

CJStefan

Senior Member
Fired up my '49 club coupe a couple days ago for the first time in the almost 4 years I've had it. It starts up super easy and doesn't overheat at all, even sitting still in the 95+ degree days we've been having. The problem is, it feels like it has no power. I want to check the timing at 2000 rpm to see where it's at (it's supposed to be 22 to 24 degrees right?).
My question is, can someone explain to me how to, or link me to the post about marking the balancer every few degrees? I've been searching for over an hour but I can't find it
 
From Bruce Lancaster
Mark on ’49-up is at 2 degrees crank… If you have an early pulley with notch, it is homemade and needs to be verified. Original mark SHOULD be checked, as not particularly accurate, and engines generally actually like a bit more – like around 4 as the starting point.
Find/verify TDC:
Heads OFF: Bolt a strap across #1, bolt through center to stop piston a ways down the hole. Rotate one way, mark pulley at stopping point, rotate other way, mark. Very accurate TDC is 1/2 way between – mark it.
Heads ON: Slide a large tie-wrap or any sort of lump on a wire through plug hole and against farthest point where it hits the wall. Have apprentice holditthere. Rotate as above… Bump, bump, divide. Repeat a couple times to be sure it is repeatable and your stop isn’t moving. Have apprentice flogged if inaccurate.
Once you have TDC nailed…
Go mug an eighth grader leaving his plane geometry class. Steal his protractor and compass, discard the rest.
Draw a circle on a piece of cardboard matching OD of your pulley. Draw a larger circle around it from same center.
Put protractor on center, draw lines at whatever interval you want – 5 degrees is adequate for estimation, can be as many degree points as you want. Mark off about 30 degrees.
Cut out inner circle, hold your new device over pulley with beginning line at your TDC, mark off rest of degrees. Can be permanent file or chisel marks, or just mark a swath with liquid paper and pencil in the lines.
You now have accurate TDC and permanent or easily re-doable scale for full range checking with a simple timing light


Crank degrees crank RPM
16* 1800
22* 2300
VAC Advance 14*@ 15”
Signal moved from timed port to manifold vacuum
 
Have you found the timing marks? The pointer on the timing cover on the distributor side. And the notch/mark on the pulley outside diameter on the engine side.
As Gene has said above you need to confirm where TDC is. Use a white or silver paint to highlight both marks and buy a timing light with built in advance. If you still have the original distributor I would just get the timing light and see what you have now. My light has advance and RPM built in.
 
CJ- If you want to mark the pulley here's how.



Measure pulley diameter. Lets say it's 6". Multiply diameter X pi. (6 x 3.14) and get 18.84"
Divide 18.84 by 360 degrees and get .052"

.052" is equal to 1 degree on the pulley.


So 20 degrees will be 1.04" on a 6" pulley.



Terry
 
I bought a set of "sticky-backed" timing strips from one of the big distributors (Summit, Jeg's, etc.). It has multiple degreed strips mounted on a backing sheet that were for various diameter front pulleys, dampers, etc. Once TDC is established, just clean off the perimeter of the pulley and apply the appropriate strip in the proper position.
 
I appreciate the responses. I did set initial timing using the pointer and dot on the pulley.i saw the timing tape set.it looks like there's one for a 6" balancer and from what I've read the pulley is 6 1/8". Of course I'm not with the car this week to verify that measurement. I plan on using the 6" tape. I may also try and make the setup Cadillac 512 described
 
CJStefan said:
I appreciate the responses. I did set initial timing using the pointer and dot on the pulley.i saw the timing tape set.it looks like there's one for a 6" balancer and from what I've read the pulley is 6 1/8". Of course I'm not with the car this week to verify that measurement. I plan on using the 6" tape. I may also try and make the setup Cadillac 512 described
Click to expand...


The 6" tape will only be .001" per degree off, so only .020" in 20 degrees. Plenty close! ;)
 
Gene1949 said:
From Bruce Lancaster


Crank degrees crank RPM
16* 1800
22* 2300
VAC Advance 14*@ 15”
Signal moved from timed port to manifold vacuum
Click to expand...

I'm trying to adjust the timing on my 1951 8BA flathead following the instructions given in this thread. I don't understand what "VAC Advance 14*@ 15” Signal moved from timed port to manifold vacuum" means. Could someone explain? I have the vacuum advance line connected to the vacuum port on the Holley 94 carburetor. Thanks.
 
Eagle43 said:
I'm trying to adjust the timing on my 1951 8BA flathead following the instructions given in this thread. I don't understand what "VAC Advance 14*@ 15” Signal moved from timed port to manifold vacuum" means. Could someone explain? I have the vacuum advance line connected to the vacuum port on the Holley 94 carburetor. Thanks.
Click to expand...

That doesn't make much sense to me either. Maybe Gene will come back and explain. If you could find Bruce's original post, that may be of some help. I don't think connecting the Load-A-Matic to manifold vacuum is ever a good idea.
 
The stock Loadamatic will have approx 15-17 degrees of advance at the crank with 3.7" of vacuum applied to the diaphragm. That's what the engine should supply by way of the carb fitting at wide open throttle and 4000 rpm (per 1951 Motor's manual) .You can check the vac advance with a hand vac pump to see if it works properly. Blipping the throttle with the vac hooked to carb should show some advance. Hooking diaphragm to manifold vac isn't a good idea, even to test.

You may see a bit more performance if initial timing is set to 4-6 degrees rather than the 2 the stock mark provides.


Don't know what Bruce's post was referencing but it wasn't a stock distributor.
 
The last load-o-matic I set up had 25 degrees total advance with no load, verified with a dial back timing light. I would be careful about adding more initial advance.
 
tubman said:
That doesn't make much sense to me either. Maybe Gene will come back and explain. If you could find Bruce's original post, that may be of some help. I don't think connecting the Load-A-Matic to manifold vacuum is ever a good idea.
Click to expand...
My Mistake. I thought the OP was dealing with a (Chev) conversion. That is the curve I've been using for many years
 
Gene1949 said:
From Bruce Lancaster
Mark on ’49-up is at 2 degrees crank… If you have an early pulley with notch, it is homemade and needs to be verified. Original mark SHOULD be checked, as not particularly accurate, and engines generally actually like a bit more – like around 4 as the starting point.
Find/verify TDC:
Heads OFF: Bolt a strap across #1, bolt through center to stop piston a ways down the hole. Rotate one way, mark pulley at stopping point, rotate other way, mark. Very accurate TDC is 1/2 way between – mark it.
Heads ON: Slide a large tie-wrap or any sort of lump on a wire through plug hole and against farthest point where it hits the wall. Have apprentice holditthere. Rotate as above… Bump, bump, divide. Repeat a couple times to be sure it is repeatable and your stop isn’t moving. Have apprentice flogged if inaccurate.
Once you have TDC nailed…
Go mug an eighth grader leaving his plane geometry class. Steal his protractor and compass, discard the rest.
Draw a circle on a piece of cardboard matching OD of your pulley. Draw a larger circle around it from same center.
Put protractor on center, draw lines at whatever interval you want – 5 degrees is adequate for estimation, can be as many degree points as you want. Mark off about 30 degrees.
Cut out inner circle, hold your new device over pulley with beginning line at your TDC, mark off rest of degrees. Can be permanent file or chisel marks, or just mark a swath with liquid paper and pencil in the lines.
You now have accurate TDC and permanent or easily re-doable scale for full range checking with a simple timing light


Crank degrees crank RPM
16* 1800
22* 2300
VAC Advance 14*@ 15”
Signal moved from timed port to manifold vacuum
Click to expand...


Do I understand that you set the timing WITH the vacuum can connected to a timed port, then move it to manifold vacuum after setting timing to the stated values?
 
Although it doesn't specifically say so, I agree with Gene that Bruce's post is for a converted SBC or other non-stock distributor. The first thing that we should all realize is that a stock Ford Load-A-Matic and a "regular" distributor are completely different animals. Although the desired end results are the same, how they get there is completely different.

To answer the previous poster's question, you do NOT switch vacuum ports. Decide what system you have and use the procedure that is specifically intended for it.

With all due respect to Mr. Lancaster, who was one of the all-time flathead gurus, his procedure as presented here is at best unclear and at worst misleading.
 
Last edited:
I understand that Bruce Lancaster and Gene were/are talking about the advance on a converted chevrolet distributor. Still many of us here use them. IF the maximum advance is set at 22 degrees with the vacuum connected to ported vacuum, it seems as if there would be only 8 degrees of mechanical advance at 2300 RPM and starting timing would be well below TDC. I realize this takes the original post in a different direction and I will try to contact Gene1949 offline.
 
Sorry guys for being so unclear.
My chevy distributer has 9 degrees (x2 for crankshaft) in it. I always set my mechanical 1st. No vacuum advance.
After establishing a good TDC I “hot time” it to these numbers and disregard initial although it figures out around 4 degrees btdc.
16* 1800
22* 2300
I picked an adjustable vacuum can that has 14 degrees in it because I do have an adjustable stop I could use if necessary.
On a test drive I plugged the vac can into the manifold vacuum along with an accurate vacuum gauge. @ 65mph on flat ground my vacuum is 15” give or take. I set the can to VAC Advance 14*@ 15”
I use manifold vacuum because of around town (cruising) drivability, idle quality AND low speed cooling.
 
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