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'81 Imperial lean burn??

Posted By: 3404

'81 Imperial lean burn?? - 06/20/08 07:53 PM

On a 1981 Imperial 318 fuel injection what is the best way to convert it over to a regular carb and distributor? Or what do I need to do the conversion? Is that what they called the Lean Burn?
Posted By: RapidRobert

Re: '81 Imperial lean burn?? - 06/20/08 08:30 PM

on my '83 cordoba 318 I kept the lean burn carter BBD which alot people have had problems with but mine is OK. The only problem is it doesn't have a ported source. You would only need an ECU,its plug in connector, ballast resistor, some wiring,a vacuum distributor & I'm sure the schematics would be in the archives. After all of that I went from 15MPG to 15.5MPG but not haveing to worry about the lean burn taking a dump on me priceless
Posted By: Alexdodge

Re: '81 Imperial lean burn?? - 06/21/08 01:15 AM

I had a 85 new yorker that kept shutting down and would not start up for at least a half hour. This got old very fast. Got rid of the lean burn but kept the carb. Easy to do and it ran great after that. Should have done it sooner. Alex
Posted By: Anonymous

Re: '81 Imperial lean burn?? - 06/21/08 01:52 AM

call brads nos
he can help you with this
Posted By: DaytonaTurbo

Re: '81 Imperial lean burn?? - 06/21/08 03:46 AM

IIRC by 81 lean burn was gone. All that remained was Electronic Spark Control. Lean Burn did not work well I guess so they dropped the computer controlled carb part of it, but kept the computer controlled ignition timing until the end of the production of carbed motors.

There is a kit out there that includes everything you need, distributor, ecu, wiring, etc. Or you can go with a 'ready to run' distributor. They make them now with the ecu built into the dist, and use a hall effect instead of the old magnetic pickup. MSD, ProComp, etc sell them. One wire to power, one wire to coil, that's it.
Posted By: 3404

Re: '81 Imperial lean burn?? - 06/21/08 10:12 AM

I will check out the kits to change it over. The air cleaner says Fuel Injection across the top of it, can I keep using that carb or will it need to be replaced also?
Posted By: 68Cbarge

Re: '81 Imperial lean burn?? - 06/21/08 10:41 AM

Here is a link to do the conversion.There is more to it than what you think-but it has been done many times before.
http://www.imperialclub.com/Repair/Year/1981-1983/Retrofit/index.htm
Posted By: dmerc

Re: '81 Imperial lean burn?? - 06/21/08 12:39 PM

Here is what I did with my 79 Volare. Bought a aftermarket HEI distributor off E-bay(new) for 78.00 delivered and hooked up two wires to the coil and drove off. By far the easiest. The distributor has a GM style module hanging off it so you have to clock it correctly for clearance. I have no idea how long this distributor will work but it looks as nice as any other I have seen. They are still listed on e-bay. Search for Mopar HEI disributor.
Posted By: RapidRobert

Re: '81 Imperial lean burn?? - 06/21/08 01:53 PM

come to think about it my '83 cordoba had the attachment on the air cleaner that said "electonic spark control" & I ASSumed that that was lean burn. It ran flawless before the change & it was only the bad rep of the lean burn that motivated me to change it & I was dissapointed that I got only a miniscule MPG improvement afterwards.
Posted By: DaytonaTurbo

Re: '81 Imperial lean burn?? - 06/21/08 03:43 PM

Yeah actually the electronic spark control works pretty well. All the 80's carb 2.2's used a computer controlled ignition timing system and they ran well with it. Downside to the ESC is you can't just go and recurve your distributor to get a different timing curve like you can with a conventional.

Lean Burn only existed in the latter half of the 70's. After that it was just Electronic Spark Control. So many people look under the hood, see the ESC computer hanging off the air cleaner and think they have Lean Burn, even tho the car does not say Lean Burn anywhere on it anywhere.

However, the OP has a car that originally had the early 80's fuel injection that chrysler put on their imperials. The early fuel injection was allegedly problematic and your Fuel Injection system was replaced by a carb many years ago, by the dealer most likely. EFI models also got Electronic Spark Control. If you do change over to a different ignition setup there is no need to change your carb. After the death of Lean Burn in the late 70's, carbs were no longer computer controlled. Because of that, there's no need to change carbs when you change your ignition system.
Posted By: 5thAve

Re: '81 Imperial lean burn?? - 07/03/08 09:34 PM

You have the carberator thing reversed. The 80s ones are feedback ones that need the computer unless its a car from Canada. The 70s ones are more normal. But no matter what one it is you still need to change it because none of them have the right port for the distributor and the leanburn ones are setup differently. Imperial should be fuel injected but I think theres more to it then just putting a carb on it and the distributor and ECU. I think the kit to get rid of fuel injection used to be pretty big and had a lot of stuff in it and think the digital dash is different too. Thats what Ive heard anyway Ive never done anything with one before.
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