Mopar leanburn distributor

Can I use the lean burn dizzy without the leanburn computer? If so what do I need to run it? Thanks later shawn

 

Reposted from the Yahoo group - Mopar C-Body Cars:

I don't have any personal experience with them, just know a group of talented people who are familiar with them.

 

With no advance, it's pretty much useless with no computer. The Mopar engine book suggests discarding everything but the coil if you have this system...

 

I have the system on my core 318. the computer is in the aircleaner horn of all places. It also received input from a rats nest of sensors. It also interacted with the Holley 6280 feedback 2 bbl carb. the computer is a candidate for the round file in my opinion. For a standalone EFI system like the Megasquirt, the distributor by itself would be considered a "locked" distributor and actually the cats' meow to use.

 

No...the Lean Burn system uses a distributor with a fixed timing setting as mentioned above, and the 'computer' (using that term loosely!) handled everything else...when it worked at all!

I've had a couple cars with the Lean Burn carb and ignition on them and they are best replaced by earlier Mopar electronic or points style distributors. Back then, you still had a halfway decent shot at finding a good small block Mopar electronic distributor in local junkyards...but I wouldn't count on that today!

The best thing to do is to order Mopar's "electronic ignition conversion kit" (through JEGS and some Mopar dealerships) for a small block (LA) Chrysler. The kit will come with a brand new electronic ignition distributor, a matching control module, ballast resistor and instructions all in one tidy package. Everything is new and factory engineered to work correctly. Seems that it runs about $200 for the complete kit these days which may sound a bit expensive...until you factor in what you'll spend running all over looking for a useable pre-Lean Burn distributor, rebuilding it with all new components, buying a new module, resistor and figuring everything out for yourself. I'm speaking from experience when I tell ya that the kit is well worth the price and that I've found Mopar electronic ignitions to run perfectly when hooked up and dialed in right! Not quite as simple as a GM HEI set-up, but it runs every bit as well!

Of course, you also need to toss out the Lean Burn carb and replace it with either an earlier Mopar two barrel that fits your manifold...or better yet, a new aftermarket aluminum dual plane intake (Edelbrock Performer tops the list there!) and any one of several excellent aftermarket four barrel carbs. For a more factory fresh appearance, you could also hunt up an early 70s cast irn 4v manifold from a 340 or 360 engine and run an old Thermoquad. They're oddball carbs to most eyes these days, but if you get your hands on a good one, they do run run!!

Just be sure that if you are using a Chrysler automatic transmission behind your motor that you run the stock TV (throttle valve) cable and BE SURE IT IS WORKING AND ADJUSTED RIGHT! You can use factory brackets and stuff to hook up the TV cable to a stock 2v or Thermoquad...or aftermarket pieces to run the TV cable on a Holley, Edelbrock, Demon or other replacement carb.

The Lean Burn design was a best-forgotten stepping stone towards EFI from the early non-computer controlled engines, and even back when it was new had a reputation for giving mechanics and owners fits! But, the engineers at Mopar's performance division didn't forsake us...and their electronic ignition conversion kits offer salvation to anyone still stuck with a Lean Burn motor under their hood!!

 

I bought an electronic (not lean burn, with mech and vac adv) LA series distributor from my local Advance for about $30, no core. Think all you'd need is a module, and the rest of your lean burn stuff (cap rotor wires coil) goes right over, minus the POS lean burn computer. If you're looking for a less cluttered look, they make HEI module adapters that tuck em underneath and eliminate the bulky mopar external module.

good luck

 

I used to run the lean burn dist on my dirt track cars. We used the run of the mill Mopar electronic ignition with the lean burn dist. We set the timing at 36 degrees when ever the motor was running. We wired it up with the ignition switch and a seperate starter switch. You had to crank over the motor and while it was spinning hit the ign switch. Instant fire! Eliminated timing issues with no kind of advance things to screw up. Doubt it would be very street friendly, but sure worked on the circle track and might work on a drag car if you could handle full advance from an idle.

So the answer is: you can use the standard Mopar electronic ignition with the lean burn dist, you just have to set your inicial timing at full advance, or whatever advance you want. Gene

 

who has them and how much are the hei module adaptors for mopars. thanks.

 

Whats the difference with the 2v carberator? The one that is on the motor is brand new and I really don't want to have to track down another different one. I'm keeping this motor pretty much stock as I've had my fill of high performance stuff(bad first experiance). later shawn

 

Came from that unmentionable auction site, the seller's name is knuttinatoll. $40.

There's likely other places who sell these, but I'm not a moparite beyond the current hot rod build, and this is the only place I've seen em. Seems a great solution for a hoodless car.

 

If it's the original Lean Burn carb, it is calibrated lean and if I recall correctly, it ties into the 'computer' in a primitive version of a 'feedback' system. On an old wagon I had, I replaced the Lean Burn ignition with standard mid 70s stuff (regular Mopar electronic ignition) and kept the stock 2v carb for a little while, but it ran like ****...better than it did with the messed up Lean Burn ignition (mine was stuck in it's closed loop "limp home" mode, which gave it no spark advance...the new distributor and module solved that, but the carb was too lean and never worked right with it). On that particular vehicle, I installed a circle track "cheater" cam (Lotsa duration with stock lift), an Edelbrock Torker 340 intake and a highly modified Holley 600 carb, along with other related mods...but if a budget-minded upgrade had been my goal, I would've simply got a stock 2v carb from a late 60s/early 70s 318 engine, rebuilt it and installed it on the original intake manifold.

Check your carb...is there any wires going to it? (I honestly can't remember if mine had any or not...I unbolted the whole intake and carb and tossed them in a pile of junk next to the garage...never looked too closely at the carb!). If you have wires leading to the carb, it likely requires some sort of input from the 'computer' on your air cleaner...or maybe it has sensors in the air cleaner, who knows?

All I can tell ya is that those engines run far better without the Lean Burn system on them. For your application, either a rebuilt early 2v carb or possible modifications (jetting, etc) to your stock carb would be the best bet. Get an earlier 2v off of a car that had an automatic, and your TV cable (if you have a 727 or 904 trans) will hook up to it like stock. Simple, cheap and easy.

 

I think the carb's only hookup was a single ground wire to idle screw area...???
It was just a crude sensor to tell the computer throttle was closed, I believe.
My memories of lean burn tech are fading fast, thank heavens.
By the way. you need to study wiring before converting to regular electronic kit...this is covered in Mopar engine book. The short take is that the wires leading to this distrib are not what you think they are, and you need to go back to the firewall and make new leads...even the resistor is different. Book says that LB instructions are NOT in the kit, and gives necessary detail;s.

 

A mentioned above...toss the carb, intake, distributor, aircleaner, and computer.

Get a non emmisions setup and bolt it on. Might as well grab a 340 4 brl intake and carb and bolt that on. It wil give a nice HP and fuel economy boost.

 

It's easy stuff, really. On my car, I used a common Chilton's manual to figure out what to change on the wiring to go from Lean Burn to standard Mopar electronic ignition, and it wasn't that hard. Thing was, the Chilton's manual was WRONG, and once I figured out the CORRECT way to wire it, I made a note in the manual. I still have that book if you get that far and need help...I can scan the diagram(s) for ya. It's REALLY simple, though.

 

I tossed all the lean burn **** and used a Mancini Racing electronic ignition conversion kit, about $200 with new coil, wires, distributor, module, and it all plugs together nicely.

 

Dangit, I figured I wasn't gonna get away easy with this motor. Yeah that carb has a wire that goes to something on the carb, looks like it might be some kind of primitive throttle sensor. I have the 8th edition of the engine book and it has the wiring diagram for the ignition system in it. Thanks guy's for the tips and help. later shawn

 

you can just run a gm hei module and mount it anywhere you want.

 

There are some great tech articles on www.slantsix.org that explain exactly what you want to do, including running the GM HEI module.