1981 Cab change?
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Racer
Joined: May 2006
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1981 Carb change?
Has anyone here converted an 81 over to an Edelbrock carb? If so, did you leave the computer controlled distributor and tranny? Did it require a different manifold? Or plate?
Last edited by docohm; Mar 30, 2021 at 08:59 PM.
Team Owner
Joined: Jan 2006
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From: Crossville TN
I would bet that for the '81 (one-year-only) engine management system to work, you need all of the stock components in place. I have no knowledge of how it would operate with a non-ecm controlled carb on the engine. If you could make it work, it would certainly need to TPS (throttle position sensor) in place on the non-'81 carb.
Last edited by 7T1vette; Mar 26, 2021 at 07:49 PM.
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From: Virginia
Lots of folks have done this. You will need to replace the distributor as well with an HEI dist with a working vacuum advance can. The transmission lockup can be accomplished, too, but requires some thought (there was a recent post on this).
Search around on the Forum. The Edelbrock carb is not held in high regard.
Search around on the Forum. The Edelbrock carb is not held in high regard.
Pro
Joined: Nov 2014
Posts: 503
Likes: 66
From: Florida
If you are going to change out the carb you will also need to get a new HEI dizzy and figure out a way to control the lock up torque converter. If you do remove the carb I may be interested if you want to sell it for the right price, if it has not been rebuilt and if it is the correct Model number 17081228. There were a couple different models for 81, one model for automatic tranny non-California, manual model and one model for California. 4-Speed Rochester M4ME 17081217
190 THM (Cal) Rochester M4ME 17081218 - California model
190 THM Rochester M4ME 17081228
190 THM (Cal) Rochester M4ME 17081218 - California model
190 THM Rochester M4ME 17081228
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Not an 81 owner, But all of the above is true. Your intake manifold should work fine however, many would be better. And a change of manifold could provide more performance and open the door to a larger selection of carbs and or EFI. as per your distributor, yes you need to change it out. G.M.performance distributor for a 80 and earlier will fit the bill nicely. as per Auto trans lock up. well, I'm no help. I'd lose the Auto trans for a manual in a heart beat. perhaps someone else can chime in as per your torque converter requirements.
Team Owner
Joined: Jan 2006
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From: Crossville TN
You should know that if you were to repair or rebuild the carb on your '81, the entire '81 engine management system could be up and running (assuming no other issues). With that system functional, upgrades to the cylinder heads, pistons, cam, crank could all be done and work fine with the '81 control system.
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
Your stock intake manifold is a spread bore. Edelbrock is a square bore. It will not fit without an adapter and I strongly recommend against it. If you find a nice Q-Jet from an earlier model, the conversion is an afternoon bolt on....distributor too.
If you want your car to run like **** and make less power, use the adapater that Edelbrock sells......If you want it to run right, either find that Q-Jet (78-80 will work).....or swap the intake for a 2101 Performer and run the carb of your choice......I have had good luck with Edelbrocks but they are not my first choice.....my First choice if replacing the intake is the 0-90670 Holley truck avenger.....best out of the box carb for mild 350 on the planet.
Holley also makes a spread bore Q-Jet replacement carb that works well too.....they still sell them. https://www.holley.com/products/fuel...parts/0-80555C.
Going to 1980 specs (mechanical distributor)....will also give you the ability to set proper timing for performance and efficiency, and a real timing curve.....something the CCC distributor can never do.
Jebby
If you want your car to run like **** and make less power, use the adapater that Edelbrock sells......If you want it to run right, either find that Q-Jet (78-80 will work).....or swap the intake for a 2101 Performer and run the carb of your choice......I have had good luck with Edelbrocks but they are not my first choice.....my First choice if replacing the intake is the 0-90670 Holley truck avenger.....best out of the box carb for mild 350 on the planet.
Holley also makes a spread bore Q-Jet replacement carb that works well too.....they still sell them. https://www.holley.com/products/fuel...parts/0-80555C.
Going to 1980 specs (mechanical distributor)....will also give you the ability to set proper timing for performance and efficiency, and a real timing curve.....something the CCC distributor can never do.
Jebby
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Melting Slicks
Joined: Feb 2017
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From: PHX AZ
They used to say the word CARBURETOR is French for "LEAVE WELL ENOUGH ALONE!"
Hey Jebby....I AM from Boston....you know what we ACTUALLY say?........ TAXI'!!!!!!!
Though I do pak my cah in the yahd!
Unkahal
Hey Jebby....I AM from Boston....you know what we ACTUALLY say?........ TAXI'!!!!!!!
Though I do pak my cah in the yahd!
Unkahal
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From: SW Florida.
the 81 carb and distributor can be perfect and the car still run like crap. the ecm is 40 years old and not reparable or replaceable. it was a desperation attempt to pass 81 emissions when they didn't have efi figured out yet. everybody who tried computer controlled carbs in that era had the same results. sucked when new and got worse with time. toss the whole setup.
Melting Slicks
Joined: Feb 2017
Posts: 3,232
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From: PHX AZ
Hey Buccy he's cutting out the middle part and adding a 'CAB' from a Desoto.
I do agree with Derek the 81 CCC carbs were 'less than desired'. I was given an 81 Citation with the electronic carb....garbage can!
Unkahal
I do agree with Derek the 81 CCC carbs were 'less than desired'. I was given an 81 Citation with the electronic carb....garbage can!
Unkahal
Pro
Joined: Nov 2014
Posts: 503
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From: Florida
I have to say, stop hating on the 81 carb and CCC setup. Most mechanics and owners don’t research how to properly setup and check all of the parts and properly adjust. I had my engine machined and I rebuilt. The carb I took to a local professional carb shop to be rebuilt and they could not get it running right after 12 attempts. I finally got my money returned, the owner could not even rebuild and set up correctly. I studied the 81 carb, read and researched, bought some carb tools and scan monitor 85. I setup the carb from scratch, checked all other parts, I found all were good and only the carb required proper setup and tune. It has been running great since. It only requires checking adjustments once or twice a year, but found it really requires no other adjustments since the computer compensates and self adjusts. It runs great, has great performance, CCC is happy and I get way better gas mileage than any other non-electronic carb. Plus did you know the 81 carb is 750 CFM.
Good luck and if you decide to rip the CCC parts out to toss away as most owners do, contact me I’ll take them.
Good luck and if you decide to rip the CCC parts out to toss away as most owners do, contact me I’ll take them.
Drifting
Joined: Aug 2019
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You can get a scanner on eBay, I have the GM scan tool , Pro Link and a Snap On brick scan tool , the Snap On Brick is probably the tool you want
https://www.ebay.com/itm/Snap-On-MT2...6-a4188760cb99
https://www.ebay.com/itm/Snap-On-MT2...6-a4188760cb99
Drifting
Joined: Aug 2019
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I agree with the other posters that the "81 CCC set up is fine. My 81 runs perfect. BTW, it's original, and I'm not racing it. Especially with 2,80's in the rear, Just about any early scan tool will work. Get an "81 factory service manual. It will tell you what to do, If you get stuck, just post here for help. The Snap on MT2500 is pretty good. If you start mixing and replacing parts, you might ne sorry.
Drifting
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