Detecting a Lean Burn conversion

[Johnny Mac]

or..don't replace anything because it's not giving you issues? all your call. depends how its running now.

but the lean burn carb was in fact lean burn specific..so i imagine it was also replaced when the lean burn distributor was swapped to the regular electronic.

 

[Fast Eddie B]

I am setting this up to go a long cross country trip. I was planning on going to EFI and by the looks of a few other threads here, there is already a well worn path to getting EFI. So what I have learned is nothing I have is original so no real reason to preserve it and it was working because it was converted.

 

[70bigblockdodge]

Lean burn carbs are just that lean burn they may have had a A/C solenoid on them but that is it, oh some TQs had a altitude compensator not he front. They were just set up to run very lean in cruise part throttle, they actually get very good mileage. That ELB box on the side of your air cleaner is the granddaddy to the MSD boxes that everyone loves so dearly but is quick to discount a lean burn system, at least Lt was a thought in the right direction (more complete combustion) instead of GM and Fords fix of we will just inject air in the exhaust manifolds with another power robbing accessory. If your car runs okay I would not sweat the carb sure you might be giving up a few ponies at WOT and a 13:1 fuel air but in a 4800# formal it's nothing you will notice.

 

[Johnny Mac]

On the flipside to the above. When you are ready for a fitech, or a holley sniper, and the supporting equipment let me know. The snipers are proving to be awesome units, and the fitechs have a $100 rebate going on. Great time to do it.

 

[Johnny Mac]

I have them in stock also
FiTech Fuel Injection


Performance/Engine/Drivetrain - Air/Fuel Delivery - Fuel Injection Kits, Components, and Accessories - Fuel Injection Systems - Fuel Injection Retrofit Kit

 

[Fast Eddie B]

If your car runs okay I would not sweat the carb sure you might be giving up a few ponies at WOT and a 13:1 fuel air but in a 4800# formal it's nothing you will notice.

The carb is ok for now, and carbs are fine in general,
but not enough people can drive carbs anymore. I share a lot of my collection with family and friends. The carbs are just too hard on the younger crowd. I love watching them jump in an old Charger and put their foot on the brake to start it!

I'm going to do it just to get it turn-key. This particular car is a favorite (77 T&C) and I want others to enjoy her!

 

[70bigblockdodge]

I understand, I am going to put EFI on my Charger but it has a ways to go before it becomes a more regular driver.

 

[fury fan]

They would not have removed the distributor to install a points style distributor. They simply converted it to electronic mopar ignition.

fact of the matter is, it doesn't much matter if its lean burn, or mopar electronic, it's fairly unreliable, and it's the absolute first thing i throw in the trash on a mopar.

IF you want to upgrade it cheaply. you install one of these...and toss all that stuff i the trash. ballost resitor, PCM, all of it.
View attachment 97556
TSP-JM6714R Mopar BB Ready to Run Electronic Distributor. Red Cap

unless it's a 383/400, and then i need to send you another link.

Oh crap, I've been driving on these unreliable mopar ign systems for years. And I'd rather have that 'junk' than some unknown distributor with unknown components in it. Where do you get ign parts for this dizzy if it dies? And where are these hardenend steel gears that the description speaks of??? And that style of distributor cap means your options for sparkplug wires went way down, unless you get a universal set and put the ends on your self (BTDT, a PITA). So sorry, I don't see this dizzy as a cure for the common cold. It's just a feel-better for people that are intimidated by the fairly-elementary and well-documented Chrysler ign wiring.

Lean burn carbs are just that lean burn they may have had a A/C solenoid on them but that is it, oh some TQs had a altitude compensator not he front. They were just set up to run very lean in cruise part throttle, they actually get very good mileage. That ELB box on the side of your air cleaner is the granddaddy to the MSD boxes that everyone loves so dearly but is quick to discount a lean burn system, at least Lt was a thought in the right direction (more complete combustion) instead of GM and Fords fix of we will just inject air in the exhaust manifolds with another power robbing accessory. If your car runs okay I would not sweat the carb sure you might be giving up a few ponies at WOT and a 13:1 fuel air but in a 4800# formal it's nothing you will notice.

I agree on all that. Later units in teh 80s also did a fuel enleanment via an electronic feedback carb, but not the 70s LBs. I have heard that many issues with a LB are caused by a poor ground path for the module on the aircleaner, and that a jumper wire to ground solves lots of issues. Learned that way after my LB was gone though, so have never tried it. But my fat 77 Cordoba 400 regularly knocked down 18-19 mpg when it was running, so I definitely would've tried that fix. I wish I knew then what I know now.

 

[Dobalovr]

The internet back in the 70's was the old guy down at the mom & pop garage. Slow downloads sometimes (5-6 beers) usually resulted in the necessary information being imparted upon the willing recipient with a "You youngsters know nuthin" I miss the Old Man Internet

 

[70bigblockdodge]

The internet back in the 70's was the old guy down at the mom & pop garage. Slow downloads sometimes (5-6 beers) usually resulted in the necessary information being imparted upon the willing recipient with a "You youngsters know nuthin" I miss the Old Man Internet

Or sometimes misinformation as shows up here with our old man with a hat internet.

But you have to love it just the same.

 

[commando1]

Everybody here realizes all cars today are "lean burn", right?
And "EcoBoost" could be said for the 85 Mustang or the 76 Regal. . .

 

[70bigblockdodge]

Oh crap, I've been driving on these unreliable mopar ign systems for years. And I'd rather have that 'junk' than some unknown distributor with unknown components in it. Where do you get ign parts for this dizzy if it dies? And where are these hardenend steel gears that the description speaks of??? And that style of distributor cap means your options for sparkplug wires went way down, unless you get a universal set and put the ends on your self (BTDT, a PITA). So sorry, I don't see this dizzy as a cure for the common cold. It's just a feel-better for people that are intimidated by the fairly-elementary and well-documented Chrysler ign wiring.


I agree on all that. Later units in teh 80s also did a fuel enleanment via an electronic feedback carb, but not the 70s LBs. I have heard that many issues with a LB are caused by a poor ground path for the module on the aircleaner, and that a jumper wire to ground solves lots of issues. Learned that way after my LB was gone though, so have never tried it. But my fat 77 Cordoba 400 regularly knocked down 18-19 mpg when it was running, so I definitely would've tried that fix. I wish I knew then what I know now.

I can believe that, but have no lean burn to check this out....... yet.
My 76 Cordoba easy 18-20 with headers and dual exhaust, stock TQ, and LB.

 

[commando1]

Headers and LB? WTF?

 

[70bigblockdodge]

Headers and LB? WTF?

I was 18 WTF, LOL.
Car would shift out of first at 72 mph in drive, that is some tall rear gears.
The other cool thing the car did was speedo would pass 100 and come back to 0 again, down hill but priceless entertainment for a 18 yo.

 

[Johnny Mac]

Oh crap, I've been driving on these unreliable mopar ign systems for years. And I'd rather have that 'junk' than some unknown distributor with unknown components in it. Where do you get ign parts for this dizzy if it dies? And where are these hardened steel gears that the description speaks of??? And that style of distributor cap means your options for sparkplug wires went way down, unless you get a universal set and put the ends on your self (BTDT, a PITA). So sorry, I don't see this dizzy as a cure for the common cold. It's just a feel-better for people that are intimidated by the fairly-elementary and well-documented Chrysler ign wiring.

As one of the few vendors that are actively on this site helping members, offering discounts, reliable products, and tech assistance to it's members... Lets get facts straight. The caps and replacement modules for these are on the shelf, and available by the thousands. Male boots are all of $15, and the modules are all of $16. You know....the price of the spare ballast resistor you keep in your glove box for when that reliable OE Ignition leaves you stranded.

If aftermarket ignition components were not relevant...Then none of you should be riding around with spare ballast resistors correct? ;)

 

[fury fan]

I was 18 WTF, LOL.
Car would shift out of first at 72 mph in drive, that is some tall rear gears.
The other cool thing the car did was speedo would pass 100 and come back to 0 again, down hill but priceless entertainment for a 18 yo.

Mine had 2.45 gears, I don't remember 1st but would consistently go to 3rd at around 93. None of my friends could believe that, so I showed them, then put it in 2nd and it did 100. Only did that once. Probably only had 10 more mph left in 3rd, wind resistance cuts top-end more than you'd think.

 

[fury fan]

As one of the few vendors that are actively on this site helping members, offering discounts, reliable products, and tech assistance to it's members... Lets get facts straight. The caps and replacement modules for these are on the shelf, and available by the thousands. Male boots are all of $15, and the modules are all of $16. You know....the price of the spare ballast resistor you keep in your glove box for when that reliable OE Ignition leaves you stranded.

If aftermarket ignition components were not relevant...Then none of you should be riding around with spare ballast resistors correct? ;)

Sorry, but I couldn't help but notice how crappy you said the factory stuff was (with no reason stated) and that you, as a vendor, just happen to sell something better (or different, anyway). Sounds a little self-serving.

What is the part# for the module, is it available in parts stores? And the dizzycap is aftermarket only, correct? Never seen a clip-on male cap be readily available. And is there an off-shelf set of plugwires that fit this dizzy and a bigblock?

My dad lost 1 ballast resistor years ago (out of 4 cars from 1978 to about 2000) , and since it was cheap and road-swappable, yes he carried one. I have never lost one, and I have never carried one.

 

[Johnny Mac]

Sorry, but I couldn't help but notice how crappy you said the factory stuff was (with no reason stated) and that you, as a vendor, just happen to sell something better (or different, anyway). Sounds a little self-serving.

What is the part# for the module, is it available in parts stores? And the dizzycap is aftermarket only, correct? Never seen a clip-on male cap be readily available, either. And is there an off-shelf set of plugwires that fit this dizzy and a bigblock?

My dad lost 1 ballast resistor years ago (out of 4 cars from 1978 to about 2000) , and since it was cheap and road-swappable, yes he carried one. I have never lost one, and I have never carried one.

I'm not here trying to be a know it all or anything. I don't think anyone could really argue with me that despite your personal experiences, the mopar oe ignition is not known for it's reliability. Thats not a jab at your car, or my car, or anyone elses car. It's a statement of fact from my experiences with it, and what the world has pretty much come to known. ( i DID tell the guy above If it's running ok...to let sleeping dogs lie) but anyways...onto my self serving vendor status

Here are the replacement modules. any Gm 4 pin will work also in a pinch. These just keep the terminals inside the case.
TSP-JM6932 - Replacement Ignition Module for Ready to Run Distributors JM67XX

Cheap plug wires (yes you have to put the ends on) ($50 cheaper than assembled)
Street Fire Spark Plug Wire Set MSD Ignition 5552 - Pace Performance Parts

or just a boot kit
Blue Max Distributor Boot And Terminal Kit Moroso Performance 72040 - Pace Performance Parts

caps are more commonly known as the 208 type. early mallorys and such
TSP-JM6971BK Top Street Cap and Rotor Kit - 208 Series Cap w/Clamp on Style Cap.

My vehicles include a 10 second dart, a roadrunner, a charger, and a ram. I've been around mopars a while. Not a know it all expert, but learned what has worked for me and what hasn't. I'm not your typical "Mopar Performance Verdor" that finds something with a little but of mopar appeal, and jacks up the price just because my last name starts with "X" "Y" or "Z"

I don't think a $72 distributor that eliminates 90% of peoples ignition woes is a terrible thing. And i'm on here throwing out free shipping over $199 and 5% off to gain your trust and business, not self promote until you guys are tired of hearing from me.

I don't take any personal offense to this, just want everyone to see where i'm coming from, and why i'm here. I was actually asked by a few members to register over here at FCBO...thats why i started posting.

 

[70bigblockdodge]

I will not be so hard on mr. Pace I have talked about the dizzy he offers. The street one is like $90 plus $12 for spare module for glove box. If I knew someone with a old dist machine I would like to take the mechanical advance curve for a spin and see if the timing retards above 6000 like a stock orange box ECU. I am not a fan of drop in replacement dizzys either, get stranded with a petronix and you basically need a whole new kit or carry a spare and I have around a $100 just sitting in my glove box waiting. I have been served well by Mopar electronic dist. but for a F.I. signal or some simplicity it may be a alternative for some. Maybe he should not POS the Mopar ECU ignition but to each his own.

 

[Johnny Mac]

I will not be so hard on mr. Pace I have talked about the dizzy he offers. The street one is like $90 plus $12 for spare module for glove box. If I knew someone with a old dist machine I would like to take the mechanical advance curve for a spin and see if the timing retards above 6000 like a stock orange box ECU. I am not a fan of drop in replacement dizzys either, get stranded with a petronix and you basically need a whole new kit or carry a spare and I have around a $100 just sitting in my glove box waiting. I have been served well by Mopar electronic dist. but for a F.I. signal or some simplicity it may be a alternative for some. Maybe he should not POS the Mopar ECU ignition but to each his own.

I went through 3 of the beloved ECU's on my dart before it was traded in on an MSD lol so forgive my bias.

The cast ready to runs are $72
the pro billets are $188
before the FCBO break.

or if you want an actual MSD, i carry those to, along with about 250 other performance brands.