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I am thinking about converting the lean burn system in my 76 Cordoba (400 4bbl). Any advise on what conversion package to use is appreciated. Also can I use the stock carburetor? If not any suggestions on a new one?

Thanks in advance.
 

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The conversion is pretty simple, remove the wiring harness of the system, you can leave the sensors in the intake, they aren't doing any harm once disconnected. Distributor has to be changed, one with a vacuum advance is best, and sorry, the carburetor has to come off, it has some inputs to it from the lean burn and there is no ported vacuum port. A matching 400 cubic inch stock carburetor will work just fine if it is not a lean burn setup, otherwise an Edelbrock or Holley will work just fine, both are pretty easy to tune. Several routes to take with the distributor, aftermarket or stock electronic ignition is available, or a stock distributor (non lean burn) will work, several aftermarket conversions for stock distributors out there, or Accel, Mallory, Mopar Performance to choose from. Given you aren't hopping the engine up and it is a low compression engine to start with, least expensive that fits the application and you are fine, a distributor from a 383 is the same for the 400. As far as wiring goes, get a wiring diagram for a 72 Dodge of your choice, follow the wiring for the electronic ignition, box, ballast resistor, etc., you will notice the simplicity compared to the monster in there now.
 

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I'll add a couple of thoughts since I perfomred a similar modification to a 1977 Cordoba years ago. Back then, I used the Mopar Performance kit. It took some tuning as the advance was more than the stock 400 engine wanted. Know what I know now, I could have used a stock distributor and wiring from a junkyard non-Lean Burn car but that is harder to do now. These are the Mopar kit instructions and the wiring is detailed there.
http://www.mymopar.com/downloads/elecignconv.pdf
The factory carb is a spread bore design. I used a Holley spreadbore that was designed specifically to replace the Thermoquad that came on these cars. I wish I'd looked instead to find a pre-Lean Burn Thermoquad. Of course, if you convert to a square bore (either by manifold swap or an adapter) you have a much greater carb choice.

Last thing is the car has terrible gearing in it. Probably 2.4 gears so it will still be slow and sluggish even after the conversion though it may be peppier than it used to be, The car really needs a 2.9 or 3.2 gear set in the rear to wake it up since it's heavy.
 
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valiant67 said:
I'll add a couple of thoughts since I perfomred a similar modification to a 1977 Cordoba years ago. Back then, I used the Mopar Performance kit. It took some tuning as the advance was more than the stock 400 engine wanted. Know what I know now, I could have used a stock distributor and wiring from a junkyard non-Lean Burn car but that is harder to do now. These are the Mopar kit instructions and the wiring is detailed there.
http://www.mymopar.com/downloads/elecignconv.pdf
The factory carb is a spread bore design. I used a Holley spreadbore that was designed specifically to replace the Thermoquad that came on these cars. I wish I'd looked instead to find a pre-Lean Burn Thermoquad. Of course, if you convert to a square bore (either by manifold swap or an adapter) you have a much greater carb choice.

Last thing is the car has terrible gearing in it. Probably 2.4 gears so it will still be slow and sluggish even after the conversion though it may be peppier than it used to be, The car really needs a 2.9 or 3.2 gear set in the rear to wake it up since it's heavy.
dana44 said:
The conversion is pretty simple, remove the wiring harness of the system, you can leave the sensors in the intake, they aren't doing any harm once disconnected. Distributor has to be changed, one with a vacuum advance is best, and sorry, the carburetor has to come off, it has some inputs to it from the lean burn and there is no ported vacuum port. A matching 400 cubic inch stock carburetor will work just fine if it is not a lean burn setup, otherwise an Edelbrock or Holley will work just fine, both are pretty easy to tune. Several routes to take with the distributor, aftermarket or stock electronic ignition is available, or a stock distributor (non lean burn) will work, several aftermarket conversions for stock distributors out there, or Accel, Mallory, Mopar Performance to choose from. Given you aren't hopping the engine up and it is a low compression engine to start with, least expensive that fits the application and you are fine, a distributor from a 383 is the same for the 400. As far as wiring goes, get a wiring diagram for a 72 Dodge of your choice, follow the wiring for the electronic ignition, box, ballast resistor, etc., you will notice the simplicity compared to the monster in there now.
Thanks, this is great information. So, a TQ carb from a 1972-75 400 (pre lean burn) and an aftermarket kit should do the trick? (hopefully). The CFM on the carb should be 650 or so?
 

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Yes, that would work. You can make the carb on there work, but that's a lot more hassle than replacing it in my opinion. The earlier 400 Thermoquad is probably tuned for a little more stout engine than yours but I'd bet it will fine.
 

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chykov's76doba said:
Thanks, this is great information. So, a TQ carb from a 1972-75 400 (pre lean burn) and an aftermarket kit should do the trick? (hopefully). The CFM on the carb should be 650 or so?
valiant67 said:
Yes, that would work. You can make the carb on there work, but that's a lot more hassle than replacing it in my opinion. The earlier 400 Thermoquad is probably tuned for a little more stout engine than yours but I'd bet it will fine.
Too; pretty much any non Lean Burn TQ will work on a stock 400, even the 1980's 360 V8 applications. :)
 

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I did this conversion on my 1978 Cordoba 400 four barrel with the Mopar Performance kit. I put it in per the instructions. I don't remember having to do anything with the advance and I definitely did not change the carb. It worked great! The guy I sold it to was glad it was already done.
 
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