[Jpaulfreeland]

Guys,

Question for 1976 Spider with SPICA.

I just upgraded my points and condenser to Pertronix module and Flamethrower coil on Bosch distributor. All new wiring including NGK spark plugs with factory gap of .025in. The SPICA pump has a manual choke in place of the Thermostatic Actuator (it's worked well thus far) and I installed an under-dash switch for the Cold-Start Solenoid because it would stick and not start when warm (also worked fine thus far). The motor is sound and healthy, great compression and no leaks or smoke. The head and cams were fully refurbished last year, no issues there. The car was running fine for the last 5 years prior to the upgrade.

Here is the problem, after the upgrade, I have sputtering, loping and backfiring over 3,000 rpm.

I've checked all timing from the cams to the distributor (with gun). It runs essentially the same regardless of advance. Starts fine, idles fine but sputters, spits and backfires once it's under load and upon deceleration… It even revs well in neutral.

I read that the car might be running really rich and might need an adjustment to the Fuel Cut-off Solenoid, but why would this be so at this stage? It may have been a bit rich before the Pertronix upgrade but there was never any sputter and just a slight (normal) exhaust gurgle.

Any ideas? I'd like to keep the Pertronix but if I have to go back to points, I will. But, it would be nice to get it working right…

 

[kcabpilot]

As far as the SPICA goes, providing that your sure start device (manual choke) is functioning properly there is nothing internally that is going to drift or require adjustment in regards to the cut-off solenoid. About the only thing that ever goes internally wrong with the SPICA pump is the compensator spring and there are ways to visually check that but since this trouble coincides with your ignition modification, If it were me I think I would re-install the points (not that hard to do) and see if that fixes the problem. If so then I'd contact Pertronix or the vendor you bought the module from. If putting the points back in doesn't fix the problem then you'll at least know your Pertronix module is not the culprit

I'm not familiar with the Flamethrower coil but the Pertronix module has a specification for coil resistance. If this was sold to you as a package I suppose it's good.

 

[MNVXer]

I'm running the pertronix and the flamethrower coil in my 78 with Webers. Works perfectly. I never had a problem after switching from the points. I did get these very symptoms when setting the timing. What did you set your timing to? For these cars its best to have a gun that lets you set the advance electronically (on the gun).

 

[Jpaulfreeland]

Thanks guys, but after much thought I called the supplier, Summit Racing. Turns out, it's the wrong part. A website glitch... Apparently, 1976 is the one year I can't get an Ignitor for with Bosch. I guess Bosch used a vaccum advance for '77 and the '75 must be different in some other way. The one i have is for a '70 wich is the wrong size engine, hence the wrong advance curve... I tired everything and thought it must be a bad part, and sure enough... I'll put the points back on and probably use the Centerline distributor option.

 

[darth dino]

i'm confused. how would swapping out the points change the ignition curve?

refresh my memory: does the pertronix use a hall effect sensor to read the lobes on the distributor shaft?

 

[kcabpilot]

Not sure about the Bosch but for the Marelli's I think the only differences were the mounting plate because early ones had a straight set of points and later ones had a curved set but it was just the mounting that differed. The module itself should have nothing to do with the advance curve, that is mechanically determined by the distributor as it changes the relation between the drive end and the cam end of the shaft. If you know the part number of your distributor go to the Pertronix webpage and put it in the search field, it will tell you the correct module for that distributor.

Pertronix Performance Parts

 

[Jpaulfreeland]

Excellent, thank you kcabpilot. I don't know what the difference is but my distributor calls for a part number from the Ignotor II product line. What I have now is Ignitor I. The part that Summit thought was correct does fit but is different enough in some way that the timing goes bad at higher rpm under load... It might be the gap between the magnet and the module. I also noticed that the magnet ring does not seat as far down as I thought it should to meat the module face. Who knows... I'll try this one:

Ignitor Kit Lookup

 

[Jpaulfreeland]

Pardon me, that was a bad link. My distributor is Bosch 0-231-178-006 and Pertronix calls for Ignitor II #92845

 

[Akram]

Jpaulfreeland you forgot to come back and tell us what the culprit was since other people may have this problem and read old threads to find a fix?