Finally Converting the Lean-Burn: Final Checklist

77newyorker440

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Good Morning Guys,
I hope everyone had a Merry Christmas and a Happy New Year!! My Chrysler unfortunately did not, as all of the sudden, it has begun running extremely poorly, backfiring, bucking, and stalling constantly. Due to this, I think it is time to get rid of the lean-burn system.
My plan is to go with a Mopar Ignition System, I am trying to find some orange plug wires to go with it, and a Holley Spreadbore 750 CFM (Which is very hard to find). I will call Holley on Monday, but in the meantime, would I be able to do manual secondaries or does the linkage require vacuum secondaries. Also, what choke type do you all recommend, I am not adverse to a manual choke. As for ignition, I plan on going with a Mopar Ignition Kit along with orange plug wires (if I can find them). Any other recommendations? Also is there a written guide on how to do this anywhere? I haven't found much.
Thanks,
77newyorker440
 

lemondana

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Holley only made a 650 vac secondary and a 800 mech secondary spreadbore carb. I don't think they ever made the 800 with the Mopar linkage. But you could get the 650 in the Mopar linkage. I don't think the Mopar carbs came with an electric choke. Why not find an early TQ, rebuild it, and than your existing choke would work.
 

CBODY67

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At this point in time, the OEM-replacement-spec Holley 4175s for you application have been long-gone from Holley production. When they were not that prevalent to start with. Which leaves the more generic StreetDemon (TQuad look-alike which fits spreadbore/squarebore applications, in 650cfm and 750cfnm sizes) or a very "one size fits all 360-440engine" 4175 (spreadbore, vac secondaries, elec choke) carb. For the air flow requirements of your engine, the 650cfm size should work fine, I suspect.

If you might not find some full-orange spark plug wires, some black wire with orande/red ends might work well, too. Finding some in a ready-made set is all the more better, to me.

Buying the Chry Mopar Perf electronic ignition conversion kit (really designed to replace a points distributor ignition) used to be the most cost effective way to do things. It had all of the necessary wiring to do the deal. The earlier Chrysler-built systems might be the best, but the later systems should still be built to OEM-standards, I suspect. Although similar kits can be had from Mancini Racing, too. Mancini's heritage included being a long-time Dodge dealer, which had a drag racing parts history, dating back to the 1970s or so. I'm not sure if any of their prior people are now running things or not.

Another trusted source is Rich Ehrenberg, who has an eBay store. A long-time Chrysler expert.

There will be some adjustments which will need to happen to the existing wiring, I suspect, which is where the supplied wiring harness will come into play. End result, you could end up with "not needed any more" items, I suspect.

The good thing is that the ELB systgem was a specific distributor and a specific fuel curve carb, both of which worked together, controlled by the computer on the side of the air cleaner. Going to a full-analog system of carb and distributor should make things work well again, typically. MANY of those cars were not converted away from ELB very well, which made them run poorly and be greatly de-valued in price, by observation.

When done, things should work/run at least as well as a 1974-spec car, I suspect. No huge power increases, but efficient reliability should be the ultimate goal.

Please keep us posted on your progress,
CBODY67
 

cbarge

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You can still use a TQ. Get a reman for a 74 440 which has the vacuum port for the distributor advance and is jetted better than the 18:1 ELB lean burn mixture carb.
Once I retrofitted an ELB TQ with a base plate from an older carb and installed fatter jets and played with the metering rod settings. Worked great!
I use the complete ignition kit from Summit.
Has a nice curve already in the distributor. Comes with the harness and ECU.
Hope this helps.
 

USSMOPAR

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There are actual instructions in the mopar performance engine book that specifically instructs how to interface oem electronic ignition to these cars and others. Wire by wire. Look in the book!
No guessing will be required. No one will have to post wild speculation. I have owned these cars and driven many miles properly configured with electronic ignition...

As for the current carb and the mysterious lean burn 18:1 bla bla bla carburetor...it will work just fine with a new ignition system so leave it alone for now. Some minor adjustments that is it, it will run better or the same depending on how the car already is

The egr should be removed and replace egr jet in the manifold with the appropriate plug. There are specific part numbers for the plug and egr block off plates in the parts book

Look in the book.

Save your money on those crappy orange s-plug wires and buy a set of firecore wires.

If you want unbolt things that should be unbolted besides the egr - unless this is your winter beater - change the intake pan gasket to block the crossover, wire open the manifold heat control valve on the exhaust and make sure you have a 195 thermostat with 60%water and 40% antifreeze.
 

CBODY67

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As for the EGR, many perceive its presence as "evil performance robber", BUT that only happens when the valve works, no other time. Therefore, just deactivating it is all that's really needed, which can be as easy as blocking the vacuum going to it. DO, though, remove and clean the valve's mating surface with the intake, for good measure, so that when no vac gets to the valve, no EGR happens.

As for the part number on the factory block-off plate, I suspect that those are now long-gone, just as similar ones from GM most probably are. Having been OEM back in the 1980s for HD truck chassis models, originally. As they were also mentioned in some OEM HP parts books, they got to live a few years longer in the warehouses, but when sales stop, as with any other part, when inventories fall below a particular level and are sold out, no more are re-stocked snf the part number is discontinued. Just the realities of the parts situation. But, if desired, it should be easy to fab one using the EGR gasket as a guide. Still, though, much easier to just kill the vac to the valve.

As to a new valley pan gasket to block the heat crossover to the intake manifold, which ALSO makes the OEM choke not get any heat to open, which then required a full-electric choke for the carb (rather than the OEM electric-assist choke) . . . I had a friend who did this on his '79 Corvette and after he got the carb recalibreated a bit, he had no real issues with cold-start driveability. At the time, it seemed that our more temperate climate in N TX helped a bit, but he also knew how to change the starting technique to compensate too, if needed. NOR did it really make the car more powerful, either!

When I installed '86 Corvette aluminum heads on my '77 Camaro 350, with no factory heat crossover passage (as manhy replacement aftermarket aluminum heads are very similar, due to fuel injection), I noticed a few things. One was that the heater got hotter quicker. The other was that I had to tweak the elec choke adjustment to get things to work right on a full cold-start situation (on an OEM-replacement Holley 4175 with full-electric choke). With no little bit of exhaust heat, it was definitely a bit more cold natured in cooler weather, as our winters have become more intense in the last 20 years. Compound this situation for a B/RB Chrysler V-8, where the intake manifold is in "open air" rather than sealing the top side of the motor. Other than heat convection from the cyl heads, the other warming air will come from air which has been heated by the radiator, which can take a good bit of run time to happen.

Therefore, any recommendation to block the heat crossover passage should be tempered to the location of the vehicle in question, to me. Plus knowing how such a change could otherwise impact cold-start performance, too. As I now know how such a change really can change things in DFW, TX, in more recent times compared to earlier times (due to seemingly yearly changes in climate), being in a colder NY climate (colder longer times) might really need the exhasut heat in the intake mainfold plenum for a better driving experience. But in Brownsville, TX or San Diego, CA, it might not be that big of a deal. Many people who are more used to dealing with fuel injection engines might not desire (OR learn or understand) how to deal with non-efi engines, whicih might lead to a "I don't like this" orientation toward older vehicles. Which might lead to a non-blanket recommendation of blocking the intake manifold heat passage on engines, especially for vehicles driven more "daily" than not. FWIW

I'm glad to know about the "factory information" on the conversion, especially as most of the affected vehicles are now in the "antique" realm of things and might not be subject to yearly emissions testing. Over the years, Chrysler used several general model-year specific color combinations on spark plug wires, but all usually had the normal resistance conductor in them. So those changes were more cosmetic than otherwise. I do concur that a newer, lower-resistance conductor might be better than the carbon-core conductor. But even then, there are some which also tend to discredit the newer conductors as "marketing hype", by observation. I have the old Borg-Warner (now "BWD" Cool-Wire, monel-wound conductor, lower resistance spaerk plug wires on every car I now have. Long term durability is great. Don't necessarily have to spend big-bucks to get that same conductor in a spark plug wire, by observation.

Enjoy!
CBODY67
 

65sporty

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A lot of the guy's here are really happy using the Edelbrock 600 with electric choke for a carb, I believe it's the 1406 model and you can get the Mopar arm for the trans linkage.
 

Dana

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You have a perfectly good Thermoquad. Leave it on there and fix your ignition problems. If you need me to tune it back in from all the adjustments that you tried to make, I will.
 

70bigblockdodge

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Follow this advice^^^^^^^^^^^^^^^^
Dave can make it run like never before. Certainly much better than a Eddy carb out of the box with it's miss adjusted float levels.
 

Mr C

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This is how I did my 77 T&C:

I stuck with the TQ and factory choke set up (ie not blocking the cross over) which I have never regretted. The TQ phenolic fuel bowls are fantastic with today's poor fuels. No hot start troubles...unlike the Edelbrock I have which struggles with heat soak issues in comparison.

The Mopar BB orange wires are not direct fit for the later 440 plug wire routing, so if you are doing a wire by wire comparison as you swap, they will not fit. There are no readily available pre-fab orange wires for the Smog era 400/440...at least none I've seen. (Are yours bad, have you tested them-or are you just swapping them on spec?).
So it will either be case of make your own wires (I haven't seen orange kits though)or non-black replacements.

I removed EGR and fabbed a block off plate for the intake...buys some valuable space in the vicinity of the throttle linkage in my opinion.

Grabbed an old 70s MOPAR vacuum distributor and ECU from my parts stash and then wired it up. I was glad I did this as I have heard that there are quality issues with both the distributors and the ECUs on the newer kits out there

I left the computer on my air cleaner to preserve the factory look...it doesn't hurt anything and looks better in my opinion.

For your consideration.
 
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70bigblockdodge

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I will even add that I would just put the car on points. Get a good used core (no wobble side to side) and just put the wire to the negative side of the coil, could not be easier. If you drive more than 5000 mile on the car in a year the electronic ignition may make more sense for maintenance. With questionable ecu, and pick up coils on the market, not to mention there are lots of the 2k Mopar kits out there with the bad mechanical advance system in them.
Biggest problem with points is
A) Chinese condensers
B) leaving your ignition switch on without the car running and burning the points.
C) maintenance hassle of changing or resetting the points after 4-5k miles.
I might add that nowadays finding a replacement ECU on a shelf at any chain auto parts is slim to none. From experience asking for the pick up coil in the distributor is is like trying to explain the math to get the Apollo moon landings done. Granted replacing the pick up coil or the ECU is rare, but aggravating nonetheless dealing with a chain store when your out on the road. Points and condenser in glovebox take up little room
 
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CBODY67

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IF you do points, be sure to LUBE the rubbing block with "points grease", of which a vial used to be packaged in every set of new points sold. With that lube, going 15K without any dwell variation was "the way it was back then". By that mileage, the contacts were usually pitted and could stand to be replaced, from what I saw back then.

CBODY67
 

70bigblockdodge

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IF you do points, be sure to LUBE the rubbing block with "points grease", of which a vial used to be packaged in every set of new points sold. With that lube, going 15K without any dwell variation was "the way it was back then". By that mileage, the contacts were usually pitted and could stand to be replaced, from what I saw back then.

CBODY67
Your probably not going to get 15k out of a rubbing block these days. Just saying. I've got 10k on the set in my Charger, had to reset gap after I had to refile surface flat.
 

CBODY67

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I noticed that back in the 1980s, many replacement points sets did not have the little vial of lube like they used to. At that time, too, I was hearing of poor durability of the points being bought. So I figured it was because the people who owned the cars, doing the replacements themselves, did not know that the point sets were supposed (or used to) to have the little vial of points rubbing block lube in them. Which then sent me on a search for such, finally noticing some lube on the wall at SuperShops, back then, which was made by Mallory ignition (which had been absorbed into the SuperShops family of parts companies, along with Sig Erson Cams). So I bought that lone tube and put it in my stash.

Back then, it was before any real push to have auto parts made off-shore had really happened, so I just suspected that the vial had been deleted for profit concerns. With "modern" customers not knowing the difference. Or that when installing the new points, that the cam lobes in the dist needed to be wiped clean and new lube applied. So everytime I found some Chry point sets on the clearance tables, I looked inside to see if the vial was in them. IF it was, I would by them. If not, I'd just shake my head and put them back. A new MP Electronic Ign kit was in the future plans, too.

Seems like the pitting is the result of the ignition capacitor's value shifting with age? But that considering that the pitting also might increase the effective surface contact area, perhaps it's not that bad, other than in cosmetics?

FWIW,
CBODY67
 

lemondana

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Years ago, at a swap meet, I found a big tube of GM point lube, hardly used. 50 cents and it was mine. It sure is handy, but I've hardly used any of it.
 

'66 Fury I

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So what is the best lube for the dist. cam these days? I've been using hi-temp synthetic multi purpose grease with good success, but maybe there is something better? Lindsay
 

70bigblockdodge

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So what is the best lube for the dist. cam these days? I've been using hi-temp synthetic multi purpose grease with good success, but maybe there is something better? Lindsay
I would say anything with high temp, gets pretty warm inside that cap in the summer. Also a sliding grease not wheel bearing so something smooth.
 

CBODY67

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So what is the best lube for the dist. cam these days? I've been using hi-temp synthetic multi purpose grease with good success, but maybe there is something better? Lindsay
Standard SL-2 Lubricam Currently on the Eckler's website. Found via Google
 

77newyorker440

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Okay, so to answer some questions, I am aware that I could keep the lean burn and the thermoquad, but I cannot bear to have the worry that it'll fail again. I see the swap as a much more reliable system either with electronic or points ignition. As for the carb, I am not planning on going with a thermoquad as I feel that they do not give the 440 the full power it has. I plan on calling Holley tonite to finalize the carburetor choice, and I will let you know how all of this goes. One question, does anyone have a link to that MoPar Performance book that was recommended earlier?
Thank you for all of the advice,
77newyorker440
 

70bigblockdodge

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MoPar Performance book that was recommended earlier
They have been out of print for a long time. You can maybe do a eBay search and one may pop up. There was a engine book and a chassis book. The chassis book will do you almost no good unless you go buy a, A,B, E body. There is a few good chassis blueprinting practices that are useful for all body lines in it. Since you don't want to use the TQ( mistake IMO, but I understand that nobody likes them so getting someone to help you work on it is frustrating). I would not go with a Holley, anything, mainly because they are insanely expensive, with the least amount of major reworking being available.
A Summit Holley clone has way more adjustability than a plain Holley, at half the price.
Hell, a Brawler is more money than a Summit clone and has a proven record, with a ton of adjustability. These are all way more carb than your car needs and it will just add to the confusion. The only one that will drive very nice is going to be in the 600+ CFM range. You IMO need at least a 750 on a 440, but being stock it will drive fair at best.
1.Replace that emission laden ignition system with anything else.
2. Send you stock TQ to Dave at Woodruff's carburetor he will fix it to run like it should.
3. Enjoy next summer cruising.

I am a die hard do it myself person and I Frankenstein'd a TQ for my close to stock 440 in my Charger. It worked very well got good MPG. After a few years it started leaking over and flooding out. Being almost winter and a laundry list of crap I need to do. I figured I would give it to Woodruff's and get it back bolt on ready, which I did and then some in the spring. It works much better than it did before. Smooth acceleration at part throttle like a electric car. I thought it ran well at WOT before and now it is just plain violent when it comes on now
 
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