Matchbox Ignition Timing

[DattoDime70]

Anyone know what is a good setting degree? I cant really find it when a timing gun or hand/ear. I got a l-16 with a matchbox(Vacuum advance connected to manifold port) Set it at 11 btdc with a timing light and still getting the same problem, I cant really find it and im getting bog and misfire and engine dies? Thank you.

[MicroMachinery]

Are you setting it with the vacuum advance hooked up? You're supposed to unhook it while you set the base timing.

 

The way I was taught to set it is to set the base timing(around 11 BTDC should be good), then to advance it until it just BARELY pings for an instant at full throttle in 4th gear. The way you do this is take it out on the road, and get up to speed at a cruise in 4th. Mash the throttle and and it should ping for just a fraction of a second.. that's about where you want it. You'll probably have to pull over and adjust a couple times to get it just right. If you're not comfortable with the thought of pinging for an instant, back it off just a little bit more.

[DattoDime70]

Are you setting it with the vacuum advance hooked up? You're supposed to unhook it while you set the base timing.

 

The way I was taught to set it is to set the base timing(around 11 BTDC should be good), then to advance it until it just BARELY pings for an instant at full throttle in 4th gear. The way you do this is take it out on the road, and get up to speed at a cruise in 4th. Mash the throttle and and it should ping for just a fraction of a second.. that's about where you want it. You'll probably have to pull over and adjust a couple times to get it just right. If you're not comfortable with the thought of pinging for an instant, back it off just a little bit more.

I had it disconnected when doing it. Ill advance it just a bit more. Thanks cause i didnt know if 11 was right. For two weeks it was running good i think i had it 12-13 but my dad moved it and messed up the timing -___-

[Sealik]

The vacuum advance should be hooked up to the base of your carb, ported connection.... above throttle plate.

Manifold vacuum is constant....which will increase base timing

Maybe................ :D

[DattoDime70]

The vacuum advance should be hooked up to the base of your carb, ported connection.... above throttle plate.

Manifold vacuum is constant....which will increase base timing

Maybe................ :D

 

I have a weber dcoe 45 9 Which has no vacuum port D: My guess it thats retarding my timing what should i do? People told me to disconnect the vacuum and drive like that haha

[Sealik]

I have a weber dcoe 45 9 Which has no vacuum port D: My guess it thats retarding my timing what should i do? People told me to disconnect the vacuum and drive like that haha

 

Ahhhh....I figured you might have a 'aftermarket' carb on there.... :)

[DattoDime70]

Ahhhh....I figured you might have a 'aftermarket' carb on there.... :)

 

Well ill mess with it ill try to find it with the manifold like i had it :) or then again ill try it with out but would something happen if i run the vacuum advance without connecting to anything:unsure:

[datzenmike]

Keep in mind the following:

1/ The faster the engine turns the more advance you need because the burn time is decreasing.

2/ The more gas and air (open throttle/full cylinder) the faster it will burn and less advance needed. The less gas and air (idle or part throttle) the longer it takes to fully burn and more advance needed.

 

 

 

If you have no ported vacuum source on the carb you can do two things.

 

Run without it. You will have the static timing of 12 degrees with the addition of 0-22 degrees of centrifugal advance beginning at about 1,000 and full in by 2,500 to 3,000 RPMs. Full throttle acceleration will be unaffected but part throttle won't be efficient and mileage and low speed will be poorer than if you had it connected properly.

 

Run manifold vacuum full time. There is little difference between ported and manifold vacuum... ported is zero at idle and is a pollution thing. All cars before the mid '50s ran this way. As soon as you step on the gas ported vacuum is applied to the vacuum advance. Ported vacuum or no advance at idle means that the engine would prefer more time to burn the weak fuel/air and without enough it will still be burning as it goes out the exhaust port. This does several things. It reduces NOx but robs the idle of power and the idle speed screw must be turned up to compensate. The exhaust port (and coolant around it) must absorb all the excess heat and the idle will run hot. Running manifold vacuum at idle will will increase the advance the motor wants, idle will increase, be smoother, run cooler. If you connect the manifold vacuum the idle speed will need adjusting down and the motor may ping slightly under full throttle at low speed, so just retard the dizzy till it goes away.

[ggzilla]

Matchbox or points, set the ignition timing to the SAME setting. Technically if you change distributors (even from points type to a different points type) you might need to alter the timing, if the mechanical advance in the distributor is different (there is a 4-degree tolerance with Datsun distributors). MicroMachinery's answer is sufficient to determine a good setting.

[DattoDime70]

I havent found the right setting i went alittle advance to 12-13 and even when i had it on 11 it would bog and misfire. And the temp would reach to the M on the gauge on the freeway but go back down to the normal mark when i get off the freeway. This never happened before until i messed with the timing and it will RUN ON when i turn it off. :unsure:

[Laecaon]

Dieseling happens... Temp at middle? Where it should be, bog and misfire, well that is not good.

[DattoDime70]

It will reach the M on the temp gauge driving on the freeway. I dont know if it can be a related problem to the timing wrong?

 

[DattoDime70]

Dieseling happens... Temp at middle? Where it should be, bog and misfire, well that is not good.

 

Yes it does it will occasionally last for 4 seconds. It could be that its too advance and the vacuum is maybe tweaking it more. I really need some help on this idk what it could be :(:unsure:

[DattoDime70]

The run on stops if i retard the timing a bit and it doesnt overheat too, But it would still misfire and turn off

[Laecaon]

The run on stops if i retard the timing a bit and it doesnt overheat too, But it would still misfire and turn off

 

Run on is simply your motor being a bit warm (not to be alarmed). Mine does it all the time. Basically the heat/compression is igniting the fuel/air mixture. I cant imagine 1-2 degrees making that big of a change. My friend forgot to tighten his dizzy down, and he was complaining of hard starts, turned out he was at like 18BTDC. I wasnt getting dieseling until I put in a 195 temp thermostat.

 

Also M is not that hot... But you really have no way of knowing what temp it is unless you can take a reading of the thermostat housing.

[DattoDime70]

Run on is simply your motor being a bit warm (not to be alarmed). Mine does it all the time. Basically the heat/compression is igniting the fuel/air mixture. I cant imagine 1-2 degrees making that big of a change. My friend forgot to tighten his dizzy down, and he was complaining of hard starts, turned out he was at like 18BTDC. I wasnt getting dieseling until I put in a 195 temp thermostat.

 

Also M is not that hot... But you really have no way of knowing what temp it is unless you can take a reading of the thermostat housing.

 

Thanks alot i was really concerned about that. Ima do the whole cooling system right after i find the right timing on the ignition. I had it right and driving fine for 2 weeks i was happy getting to drive it to school, then my dad had to move it cause of the gauge and i cant seem to find it anymore <_<

[ggzilla]

Plug your vacuum advance hose and drive it around. you can drive it that way permanently, it won't hurt the engine (though fuel economy may suffer).

 

If the problems go away, the vacuum advance can may be leaking (super, super common). or it may not like the full vacuum at idle.

 

Don't fall into the trap of trying to adjust the timing for the smoothest idle, instead use the air/fuel mixture to get a smooth idle. Adanced users can tune timing for the total advance like MicroMachinery advised. All others should set it 7-10 whichever is the stock setting.

[banzai510(hainz)]

I thought we went thru this already on the other thread.

Plug that manifold hole!!!!!!!!!!

leave the dizzy open

try 12 -15. it still bad then go down in timming then drive it.

 

adjust the dizzy. drive it. adjust dizzy again drive it.See what happens.

 

more or less what GGZILLA just said above

 

to stop run on I just push down on the pedal when I turn the key off

 

 

Like I said earlier most bigger sidedrafts dont have a vacuumline and wasnt meant to run one. Usually the dizzys are recurved for those with a faster advance so most vac adv not used.( but Im part guessing on this) Evertime I see a Line on a side draft you have to figure its getting pulasated inputs from the piston going up and down so its not constant.If at the carb its weaker so its not a great pull on the dizzy.

So lets makes this simple and try the above method first. If dont work you got other issues maybe.