Thanks for all the help everyone.



Steve, it is the 8383 with the vaccum advance and I do have it connected to mani.



I have left the blue (stock) bushing in and am trying one heavy and one light silve spring. MSD says this should give me 21˚ at about 3500. I am either going to have to buy a timing light with cal. controls or tape the balancer. I have been using a light on it but am nowhere near the marks so I am guessing the pulley/balancer slipped on the hub? I basically did what MSD suggests and gave as much initial as I could until I had a hard start (and backed off a degree or two @ the dizzy). The car starts with the slightest turn of the switch and idles/runs smooth. The reason I am brought the post up was to get a good starting baseline for the curve and eliminate that as the source of a small but annoying stumble at low speed. I wanted to eliminate the curve as the source of the problem and move on to the carb (already tried messing with secondary springs there.



Thanks again everyone,



Mike

M_S......Mike, does your distributor have vacuum advance too? or only mechanical?

 
 Steve Metzger       Tucson, Arizona

I edited the map for more even more older guys.

Now there is the Inches of Mercury-chapter too.



When I generated that map the first time, I started with Eickman's book and then compared it to other engine's, dyno-proof maps(V8,L4,..).

I found that original vacuum curve is not progressive like others.

Vacuum stands only full, not half throttle.



...but that map is not dynotested, I tested it only with my a**.



Hyvinkää, FI

Referring to these handy charts, Sun electric showes what looks like two distributors, with two sets of advance for the 1956 Ford 272:

FDS12127A

Dist RPM           Vac.    Dist. Deg.

300                   .15"     0-1/2 deg

400                   .28"     1/4 - 1 1/4 deg

800                   .96"      6 1/2 - 7 1/2

1200                  2.21"    11 1/2 - 12 3/4 deg

1600                  3.41"     14 1/2 - 15 1/2 deg

2000                  4.60 "    16-17 1/4 deg

FDS12127B

300                   .16"       0-1/2 Deg

400                   .29"       0-1 Deg

800                    .88"      5 1/2 - 6 1/2 deg

1200                  1.27"      8 1/2-9 1/2 Deg

1600                  1.73"      11-12 deg

2000                  2.19"       13-14 1/4 deg

The Ford 1956 292 is identical to the second set above.

 

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

So Chuck - Here is my guess (I've missed my share today).

The chart shows absolute pressure on the left axis - 14.7 psi is atmospheric pressure at sea level - so anything less is actually what is normally called vacuum (here in the USA). We old Americans on the other hand, are used to dealing with inches of Mercury - which can relate to this chart if you can find a conversion factor.

On the technical side - I assume that this spark advance curve is programed into a little logic controller that reads the absolute manifold pressure of the engine, the current rpm - and looks up the required number on this chart (at something less than the speed of light).

I'll see if I can find a nice conversion factor somewhere or invent one as the case may be ........ 

 
 Steve Metzger       Tucson, Arizona

HAHA! Sorry I forgot.

Here is a new updated picture for you old American men.



So 100 KPa / 14.5 PSI is athmosphere pressure, throttle plates wide open.


Hyvinkää, FI

For those of us from your dads generation please explain! All of your stuff is interesting but often goes right over the head of us old redneck Ford guys. Chuck in NH (born in Missouri)

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

The explanation of what a "kilo-Pascal" (kPa) is - to an old time redneck Ford guy like my Dad would take days - I can just imagine.........................

 
 Steve Metzger       Tucson, Arizona

Total advance map is from stock '59 292 and I dont say it's perfect, but it worked last summer quite well.



I hope this helps.


Hyvinkää, FI

MS:

I don't have the loadomatic specs at hand, but I don't think you want to use those specs anyway.  Limit your total distributor advance to 10 degrees (20 crankshaft degrees), all in by 3000 rpm.  Set the initial at 14 degrees to give a total crankshaft degrees of 34.  If it doesn't like this much initial, add a couple degrees to the total and adjust the initial to suit you.  This is without vacuum advance being used.

John

John - "The Hoosier Hurricane"