Electronic Distributor Upgrade - Low RPM/Load Misfires

[BrandonS]

Sorry for the resurrection, but if it helps anyone later on that stumbles onto this...

 

I never could get it to idle very well, the distributor always gave me kick back problems on starting and had misfires at idle, but the points distributor had no problem starting or idling great with the same timing dialed in. I’m reasonably sure i had a bad distributor from the get go or at least something screwy with it.  It just died a day ago and left me with no spark. 

 

Since I could originally find no definitive answer on my timing marks online, to clear up the confusion I left this thread with for anyone that comes across it in the future, and to be prepared for my next step I wanted to be 100% sure of the timing so I did what I should have in the beginning. I popped off the valve cover and aligned the cam for TDC. In the previous pictures TDC is the timing mark with the orange/pink nail polish. 

Edited September 10, 2018 by BrandonS

[Charlie69]

On 8/18/2017 at 11:37 PM, BrandonS said:

I still have the ballast resistor wired in and have a new coil.  It says on it to use it with an external resistor.  It's an Airtex Wells 5C1057.  The plugs are the same plugs that were in the car with the points distributor and are in perfectly fine shape.  I do have another set of new NGK 4006.  The distributor was a brand new reman unit from A1 Cardone.

 

Oh and it also will do tiny little burbley backfires when decelling.

A1 Cardone "rebuilt" parts get a half ass cleaning, painted, boxed, and shipped.  I purchased a matchbox distributor, a brake power booster, and a brake master cylinder that were A1 Cardone and all these parts looked dirty out of the box,  all were bad or failed within 2 weeks out of the box.  No more A1 Cardone for me.

 

The matchbox distributor is designed to use a full 12v coil no Ballast reducer..  Did you use the distributor pedestal from you original distributor?

 

I order a 12 volt matchbox distributor coil for a 1980 720 L20B from Rock Auto and received a coil that required a ballast resistor.  If you run a coil that requires a ballast resistor with out a ballast resistor it will get real hot and the is a chance that it can blow oil all over your engine bay.

 

Get the correct coil for it it is not getting the 12v that is needed for correct spark.

 

Please state what year you car is there could be emission parts causing some of your problems. Also did you have a dual points distributor?

Edited September 11, 2018 by Charlie69

[banzai510(hainz)]

You dont have to pop the valve cover to help find TDC. You just got to open the oil cap and youll see the exhaust valve nearing the 10 o clock position you know your comming up to TDC and look at the crank timming slots. and dial up to it them pop the dist cap and see where you are. 

 

 

One can run the stock point coil and ballast if a Matchbox is installed. It will be more of a Pertronix set up hook up with the wiring.  Still better points!

[BrandonS]

15 hours ago, Charlie69 said:

A1 Cardone "rebuilt" parts get a half ass cleaning, painted, boxed, and shipped.  I purchased a matchbox distributor, a brake power booster, and a brake master cylinder that were A1 Cardone and all these parts looked dirty out of the box,  all were bad or failed within 2 weeks out of the box.  No more A1 Cardone for me.

 

The matchbox distributor is designed to use a full 12v coil no Ballast reducer..  Did you use the distributor pedestal from you original distributor?

 

I order a 12 volt matchbox distributor coil for a 1980 720 L20B from Rock Auto and received a coil that required a ballast resistor.  If you run a coil that requires a ballast resistor with out a ballast resistor it will get real hot and the is a chance that it can blow oil all over your engine bay.

 

Get the correct coil for it it is not getting the 12v that is needed for correct spark.

 

Please state what year you car is there could be emission parts causing some of your problems. Also did you have a dual points distributor?

The engine is the stock engine for my car.  71 510 w/ an L18 w/ SUs (KH510).

 

Passed this thread, I ended up using a Summit coil, much akin to a MSD Blaster 2.  I had it wired so it was all receiving 12V when running.  The car ran great at speed, but the idle was never very good and the timing was constantly jumping around on it even with the vac advance disconnected.  I would put the points distributor back in, put the wiring back through the ballast and the idle would go back to butter smooth (but suffer on the top end).  

 

The pedestal was not the matching one for the new distributor.  I was able to work what I had with a dremel though and it all worked perfectly; with a timing light it matched up to the points.  

 

This will all be for naught this winter when I'll start building and installing a CA18DET I picked up.  I just wanted to update the thread in case someone had the same engine/crank pulley as I did.  I didn't want any previous information to steer them wrong.  I know I couldn't seem to find the info anywhere.

 

8 hours ago, banzai510(hainz) said:

You dont have to pop the valve cover to help find TDC. You just got to open the oil cap and youll see the exhaust valve nearing the 10 o clock position you know your comming up to TDC and look at the crank timming slots. and dial up to it them pop the dist cap and see where you are. 

 

 

One can run the stock point coil and ballast if a Matchbox is installed. It will be more of a Pertronix set up hook up with the wiring.  Still better points!

 

Yes you are correct.  The problem was that I had no idea with 100% certainty which mark was TDC.  I couldn't find anything online and noone that commented here was sure.  That left me moving it back and forth trying to feel which "felt best."  I just wanted to be sure.

Edited September 11, 2018 by BrandonS

[banzai510(hainz)]

Its nice having a nice spare distributor for trouble shooting. Its a fast 15min ck to rule the distributor out then one can look at the carb

With a point type its worse as the bushing wear and throw the points specs out. esp at High RPM it will cut out. Even with my pertronix conversion added.

also with points uyou have the condensor going bad or not grounded good issue

 

also fatiuged springs or weights falling off

Edited September 12, 2018 by banzai510(hainz)