'79 Cordoba / 911

[ybshore]

My '79 Cordoba with 31xxx miles was butchered and abandoned of its ESI and components by the former owner. I have been simply trying to create an aspirated 360 2bbl since. I have replaced ICM, Ignition coil, distributor entirely, plugs, wires and rebuilt the Holley. And cleaned the negine bay of vacuum and electrical wires not connected, yet still the car is running at idle OK, but shudders and spits under any load. Pleanty of good fuel is there, yet the car runs like poop. The tranny is fine with fresh fluids and known driveability. My mechanic seems to think ignition somehow as it feels as if it is cutting out when we take her out for the car runs just not right. Is there something I should be reconnecting which is outside of the realm of the ESI yet integral to running operations? An emission issue? Seeking any input. THX. Jack

 

[Jonnyuma]

Not ignition related, but make sure the choke is open, the pcv is working and not clogged, and check for vaccum leaks....everywhere. If you're using the factory carb and intake there could be hidden vacuum taps that still need to be plugged. Attatch a vacuum gauge (at a port BELOW the carb's butterflies) and adjust the idle screw(s) for maximum vacuum, should be a steady 15-17" at idle. If its steady but low, find the leak. The timing could be off, or there could be something amiss inside the distributor. Was it new, or a junkyard score? Vacuum advance?

 

[rumblefish360]

ESI?

Speaking strictly ignition, use a vacuum advance distributor and a chrome box with the proper ballast. And/or a MSD or equal system with the previously mentioned ignition as a back up. I used this set up on a dead stock '79-360 Magnum. It later got a Carter 600 on top of a OE 4bbl. and dual exhaust off the exhaust manifolds. The OE ignition was just simpley discoennected.

 

[ybshore]

Bbrand New spec'd distributor with adjustable vac advance; new ballast, pcv, plugs, wires ECU, coil, and rebuilt stock Holley 2bbl. It runs better without the vacuum advance connected...every carb port is properly capped and various sensors capped as well.....idles awesome, but backfires and skips underload indescriminantly....we are stumped...we have specs set according to the FSM and the MoPar electronic conversion instructions and we remain stumped..what are we missing?

Not ignition related, but make sure the choke is open, the pcv is working and not clogged, and check for vaccum leaks....everywhere. If you're using the factory carb and intake there could be hidden vacuum taps that still need to be plugged. Attatch a vacuum gauge (at a port BELOW the carb's butterflies) and adjust the idle screw(s) for maximum vacuum, should be a steady 15-17" at idle. If its steady but low, find the leak. The timing could be off, or there could be something amiss inside the distributor. Was it new, or a junkyard score? Vacuum advance?

 

[Jonnyuma]

Are you connecting the vacuum advance before or after the throttle plates? It should'nt idle better OR worse w the vac adv disconnected because the vac adv shouldn't be advancing at that rpm. If you have it connected after the throttle plates it will be advancing at idle when vacuum is at its highest causing waay too much initial timing. It needs a port before the butterflies so it doesn't get sucked-on until the throttle plates start to open, rpm goes up, and the need for more spark advance emerges. That's pretty basic stuff, and you probably already knew that, but besides a mechanical defect w the new dist, that's where I would be checking.

 

[ybshore]

I should have said idles fine either way, but under load without vac adv connected it runs nearly smooth, but connect that vac advance and push the acceslerator and you'd think I have spark plug wires backwards.....

 

[rumblefish360]

Check inside the distributor for a good clean, easy free moving parts that are in corroded.
Did you rebuild the carb?

 

[ybshore]

New distributor and rebuilt Holley 2bbl with ported vac.

- - - Updated - - -

Electronic Spark Ignition was the version in '79...

ESI?

Speaking strictly ignition, use a vacuum advance distributor and a chrome box with the proper ballast. And/or a MSD or equal system with the previously mentioned ignition as a back up. I used this set up on a dead stock '79-360 Magnum. It later got a Carter 600 on top of a OE 4bbl. and dual exhaust off the exhaust manifolds. The OE ignition was just simpley discoennected.

- - - Updated - - -

Electronic Spark Ignition was the version in '79.....

ESI?

Speaking strictly ignition, use a vacuum advance distributor and a chrome box with the proper ballast. And/or a MSD or equal system with the previously mentioned ignition as a back up. I used this set up on a dead stock '79-360 Magnum. It later got a Carter 600 on top of a OE 4bbl. and dual exhaust off the exhaust manifolds. The OE ignition was just simpley discoennected.

 

[ybshore]

With all directions followed per specs, double checking everything, and then re-checking, what I am left with is this: the holley is ported. If base timing is set to 5 degrees with total mechanical and vacuum to 50 degrees, the car will backfire through the exhaust and not run 20 feet. When we move base timing to 25 degrees BTDC, the total timing advance mechanical only moves to 45 degrees and the car backfires throug hthe carb. Disconnect vacuum and run at Base 25/Mech to 45 BTDC and there is mega improvement. I do not wish to push the timing as such, but please I'm taking all suggestions as we have been at this point with this 360/2bbl for two weeks now and have reached our wits end. THX.