Lean burn replacement?

dodge1972

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Planning to replace lean burn system on a 75 Cordoba 400. Request a few details regarding the procedure: Install a standard distributor with control ignition module and wiring. Also plan to install a new carburetor. Remove old air cleaner and related wiring. What else? Other requirements??
 

BeatersRus

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theres a ton of vids on youtube about this,and also topics here in the forum.
basics,they sell a complete mopar swap kit on ebay for the distributor and electronics.
make Sure that you specify that you have a 400 Low Deck big block.
the 440 is a tall deck.

as for the carb,it depends if stock and how you use the car.
if its a cruiser/stock,then an Eddy carb would be perfect.
if its got some juice,ie,cam intake n all that,then a holley street demon or an older thermoquad would be my choice.
i will add to those by saying to make Sure that you have your kickdown for the transmission setup Correctly no matter which carb you install <> it is critical to your transmissions life.
some people will attempt to make a 2bbl linkage setup work,others will make their own linkage combos,and you can also buy Cable setups that are much nicer and easier than our factory linkage.
 

s/w theo

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I did this conversion to my 77 Cordoba, same engine too. I just installed a Mopar Performance electronic ignition conversion kit on it. All the instructions were there to tell me how to do a Lean Burn swap (must have been a pretty popular thing to do back in the day. The Lean Burn set-up was lousy) I kept the Thermoquad that was on the car, just rebuilt it, removed the computer, wiring etc. I don't know who makes a good conversion kit anymore, I did the install over 35 years ago, but the car ran great after that. No pinging all of the sudden, all Lean Burn stuff related problems, GONE! Everything that was needed was in the conversion kit, not much to swapping the ignition over. Worth the effort.
 

HALIFAXHOPS

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Just a FYI. When you buy the conversion kit make sure it has a curve similar to the one you have and also a quality ECU not one that says "replaces xxxxxxx".
 

s/w theo

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Just a FYI. When you buy the conversion kit make sure it has a curve similar to the one you have and also a quality ECU not one that says "replaces xxxxxxx".
Very good info from HALIFAXHOPS. I don't know who makes a good quality conversion kit these days. Most are Chinese junk. You would probably be better off buying all the components from HALIFAXHOPS (distributor, ECU, ballast resistor etc. He may even HAVE the ECU wiring harness) Or you can get the ECU wiring harness from Summit Racing & it's supposed to be a good piece.
 

WileERobby

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I did this conversion to my 77 Cordoba, same engine too. I just installed a Mopar Performance electronic ignition conversion kit on it. All the instructions were there to tell me how to do a Lean Burn swap (must have been a pretty popular thing to do back in the day. The Lean Burn set-up was lousy) I kept the Thermoquad that was on the car, just rebuilt it, removed the computer, wiring etc. I don't know who makes a good conversion kit anymore, I did the install over 35 years ago, but the car ran great after that. No pinging all of the sudden, all Lean Burn stuff related problems, GONE! Everything that was needed was in the conversion kit, not much to swapping the ignition over. Worth the effort.
It certainly was a common fix back in the day.
 

dodge1972

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Just a FYI. When you buy the conversion kit make sure it has a curve similar to the one you have and also a quality ECU not one that says "replaces xxxxxxx".
What is a curve similar? I believe your referring to limiting the distributor overall advance using a higher initial. Or perhaps an RPM Limiter?
 

HALIFAXHOPS

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No each engine even stock have a advance curve to help the engine perform its best. Your FSM should have the stock specs in it say 5 at 700 rpm 7 at 1200 rpm etc.
Most of the lean burns are locked out in the distributor. Watch the kits seriously most of the new ones have overseas built ECU's with a fake transistor on the heat sink and the one that is actually used is inside the potting and overheat and fail. The words "authorized and replaces" Run
 
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casey henson

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I did my '77 400 summer before last. I used a Mopar performance distributor kit and an edebrock avs2 carburetor. You will need an adapter plate under the carburetor if you run a square bore.


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dodge1972

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dodge1972

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No each engine even stock have a advance curve to help the engine perform its best. Your FSM should have the stock specs in it say 5 at 700 rpm 7 at 1200 rpm etc.
Most of the lean burns are locked out in the distributor. Watch the kits seriously most of the new ones have overseas built ECU's with a fake transistor on the heat sink and the one that is actually used is inside the potting and overheat and fail. The words "authorized and replaces" Run
Words of wisdom and good advise are always appreciated.
 

ZR9B

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does the "Mopar electronic ignition" kit and a carb swap fix this??? ...that's kinda how I remember it. but I could be wrong
 

HALIFAXHOPS

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It will change out the lean burn ignition. But again, make sure the curve is comparable, most of those go in full advanced quickly and are also made out of the country.
 
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