78 Lean Burn computer question

I have a 78 360 lean burn volare with a 4091732 spark control computer. I was looking to carry a spare computer just in case. I can`t find that part number. Will another part number for a 78 360 lean burn work? I am wondering how interchangeable they may be. Trying to keep the lean burn system original.

Hope this helps a little. It's a page from the 1993 Mopar supersession book where it shows the 15 part numbers that supersede to and from the number you supplied. There is an arrow pointing to the supplied number.

This is a great list. I have an original survivor 1977 Cordoba with 13K miles. I too am looking for a spare spark control computer to keep on hand . The part no. on my computer is 4091440. I don't see it on this list.

Thanks for posting this list. Is there another page more part numbers. Like I mentioned below I need to know what part number replaces 4091440 which is marked on my original spark control computer. Here is a picture of the part no. on my computer. It doesn't seem to be on the list. Thanks again.

Thank you for the list.

Just google your number.

ok I found that 4106068 and 4106086 will interchange 4091732 ,Thanks all

Found one NOS in a sealed box . Thanks to all that helped.

Here's the list for 4091440

Glad you found the part.

Do any of those replacement part numbers alter the air to fuel ratio to make the engine run smoother than the Chrysler original?

Have a vented distributor cap:

https://www.cartalk.com/content/i-bought-new-chrysler-cordoba-lean

I wonder if modern Irridium tip spark plugs would help?

I have often wondered how lean a a/f mixture
a modern twin spark plug variable valve timing 5.7 V8 could get to
with an aftermarket EFI like the Megasquirt.

At the Australian Autospeed website years ago there was a review of an Australian spec Honda Insight that leaned its gasoline engine highway cruise air to fuel ratio out to 25 to 1, and the liters per 100 kilometer dash display got above the equivalent of 60 miles per USA gallon.

I cannot find a link to the article through Google search
but all the Autospeed articles are in the Wayback machine of the Internet Archive.

Of course 50 to 1 air to fuel ratios used to be common at highway cruise on 1980s American diesel pickups.

https://www.sae.org/publications/technical-papers/content/880291/

You can still legally do lean burn in the USA on natural gas generators, with the economics favorable around 2000 hours of operation per year:

https://www.generac.com/Industrial/GeneracCorporate/media/Library/email/Rich-Burn_FactSheet.pdf

Detonation danger goes down at very lean mixtures.
At 23 to 1 air to fuel, compression ratios of 15 can be used, says German test engine results:

https://www.sae.org/publications/technical-papers/content/2021-24-0034/

Good question, It kinda makes me wonder if they did make changes with every new superseded part number.

I have 2 of these KAL 2969 spark analyzers and have found them useful.

https://www.ebay.com/itm/3052253888...DjXYqPdGJ2AlKLQNy%7Ctkp%3ABk9SR8DckcvvYg

They clip around a ignition wire and give continuous digital readouts for an individual cylinder of:

peak kilovolts (what it takes to jump the gap and begin the spark)

burn kilovolts ( lesser amount of kilovolts to continue the spark)

burn time (thousandths of a second the spark endures)

These numbers can be used to tell whether a cylinder mixture is rich or lean,
and whether compression in that cylinder is good or poor.

Such a meter and readouts might be useful on a lean burn system

I am attaching two photos from the KAL 2969 manual pages that explain this ( hope they are in focus good enough to read)

My lean burn on my 78 fury is going where it belongs. In the trash.

Thank you so much.

Thanks to everyone for the help.

You can buy any number and it'll work, but make sure yours has only one set of plugs, some later ones had 2 plugins.

Leanburns had their issues, but I have 2 of my 4 Magnums still using them.