440 six pack not running issues

[rklein71]

My current project, 71 BG. I put in a 408 and a four speed. I had a 440+6 in my 69 383-s for nearly 25 years. I sold the engine to rebuild the original 383 and sold the car to fund my 71 project.

 

[Jimmyspeed59]

I bet that was a bad 69 with that 440 in it. I’ve done several Chevy restorations but I must say this mopar has been the most challenging. Definitely harder to find and buy parts. Good luck with your 71

 

[Steve340]

Have you checked the wiring in the loom from the firewall plug. Any replacement wiring may not be terminated correctly that would give you a weak spark.
Try another coil also.
You could run the ignition straight off the battery with jumper cables for a test.

 

[Jimmyspeed59]

Have you checked the wiring in the loom from the firewall plug. Any replacement wiring may not be terminated correctly that would give you a weak spark.
Try another coil also.
You could run the ignition straight off the battery with jumper cables for a test.

I guess I could just run a hot straight from the battery to the “run” side of the ballast resistor that would take the ignition key and under dash wiring out of the loop and see how long it runs then. Of course I better remember to take it off when I shut the car off. Thanks for you reply

 

[DTCMMLF]

Remembered reading this post a while back on the fuel issue.
Maybe some hints and tricks to assist you with your 6 Pack.
6 pack tuning

 

[Jimmyspeed59]

Remembered reading this post a while back on the fuel issue.
Maybe some hints and tricks to assist you with your 6 Pack.
6 pack tuning

Thanks for the thread do good info in there

 

[i_taz]

Hate to jump the thread but what's your tire wheel package...???

 

[Jimmyspeed59]

No problem the rims are 17x8 front and 17x9 rear can’t remember what size cooper tires. I have to look when I get home. The rim package came from year one and uses standard stock center caps

 

[i_taz]

Thnx... and don't get frustrated building your 1st Mopar. It will be worth it.... As for parts I got burned out back in the 80's when you couldn't buy a 4-sp shifter and the only sheet metal available were quarter skins. Today I'm amazed you can get a screw for a '64 Valiant headlight bezel. Shouldn't have waited so long to get back into the hobby but really had no idea how far parts availability have come.

 

[Doc Corey]

You need a lot more that eight volts at the coil with engine running. Charging at 14.2-14.4, you should have 11-12vdc at coil. Don't freak on what should work, freak on what DOES work. You have the wrong resistor. There's an old saying in motorcycle mechanics: "90 percent of carburetor problems are caused by the ignition system".

 

[DTCMMLF]

Doc,

Initially, I was going to comment that there should be 12.5 to 13.5VDC at the coil. However, being made to look foolish on too many assumptions in the past, I decided to check first. Measured my RUNNING 340 at the coil the other day with my good multimeter. Ignition on, not running, 13.2VDC. Running, 8.8VDC.
Think the meter is reading an average voltage. The voltage is pulsing??? Also thought the resistor was only used during startup to limit the current flow thru the ignition system due to huge pull for the starter. Back in the old days, the resistor limited the current to save the points during startup.

 

[Jimmyspeed59]

Back in the 60s and early 70s the resistor was used to reduce the voltage during running to save the points and when you turned the key to start you essentially bypass the resistor to send the full 12volts to the coil to help the motor start. Once started the voltage now goes through the resistor to the coil at 8 to 9 volts to help save the points from burning up so fast. Chevys were the the same way. Changed many of points in my day when I was a young hot rodder.

 

[Doc Corey]

f

Doc,

Initially, I was going to comment that there should be 12.5 to 13.5VDC at the coil. However, being made to look foolish on too many assumptions in the past, I decided to check first. Measured my RUNNING 340 at the coil the other day with my good multimeter. Ignition on, not running, 13.2VDC. Running, 8.8VDC.
Think the meter is reading an average voltage. The voltage is pulsing??? Also thought the resistor was only used during startup to limit the current flow thru the ignition system due to huge pull for the starter. Back in the old days, the resistor limited the current to save the points during startup.

 

[Doc Corey]

I will say, it's hard to get an accurate reading on a coil primary with a digital meter. Do you know what the charging system voltage was at the battery during the test on your 340? I'll measure the voltages tomorrow on my Cuda and see what it says. These old cars ran dirty rich and didn't strain the ignition the way cars do these days. Some cars bypassed a resistor at starting to provide (to the coil) full battery voltage while cranking (11vdc or so) and then the resistor would choke the voltage down to that 9-11 volt range to protect either the points, the coil, or both. A lot of modern coils will eat 13-14 vdc with no problem and need no resistor. But eight volts while running will cut your primary current way down. It could be that there is so much resistance in this car's primary ignition (harness, ign. switch, etc.) that it's not getting the 13-14ish (engine running) volts to the upstream side of it's ignition resistor in the first place. I would place a jumper wire from the battery, with a fuse...., and toggle switch, and hook it directly to the NON-COIL side of the resistor and then see what the voltage is on the coil side of the resistor, with the engine running, and see if it clears up the problem. That will tell the story. Writing this, I realize I can't recall exactly what coil and ignition it has. Assumptions........cheers.

 

[Jimmyspeed59]

UPDATE!
Well the challenger is running better now at least it doesn’t shut down in 10 minutes. Changed spark plugs to champion J12YC’s installed new FBO ecu and flame thrower coil, bypassed the resistor (see photo). Also tuned carbs some more. The back carb was rich had to adjust the mixture

screws on the bottom. I still don’t think I’ll ever get rid of the gas smell though. Now my new problem is when I give it some gas on the road the motor starts detonating and pinging. I got around 15 degrees initial timing because it has good idle and vacuum there. I guess I’m might have to lock out the mopar electronic distributor with one of those lock plates from FBO. I’ll keep plugging though getting closer to the finish line with this challenger.

 

[Doc Corey]

I'm gonna go out on a limb here, as I have heard that Mopars ran more ignition lead because of the gear reduction starters, but 15 sounds like a lot of lead. If it's pinging, there's either too much initial lead, or high-compression/fuel octane. Try it at 10-12. The bumped up initial timing may be masking some carb imbalance or vacuum leaks. At least you can now drive it...