81 adding intake question

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Feb 12, 2018 | 09:25 PM

clifish

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From: St. James NY

81 adding intake question

I know this will make the more experienced C3 guy roll their eyes but I have been back 25 pages on this forum and get conflicting answers.

I have a 4 bolt main motor that appears to be from a late 70's to early 80's van/truck in the car....appears stock with air pump and original 81 manifolds. I have a true dual, cat delete magniflow exhaust. I can get the edelbrock 2101 intake and a HOLLEY 600 CFM CARB for cheap. Is it worth it....would I be better keeping the orig Qjet carb instead?

I get that heads/cam would help but If I go that far I would just get a crate motor and not ready for that yet.

Feb 12, 2018 | 09:40 PM

Big2Bird

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Your running without the ECM now?

Feb 12, 2018 | 09:43 PM

clifish

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From: St. James NY

yes, I have the ECM

Feb 12, 2018 | 09:50 PM

clifish

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From: St. James NY

If the Holley adds no value I could easily sell it and recover money on the manifold? will the manifold be worth the time to swap?

Feb 12, 2018 | 09:51 PM

Big2Bird

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Quote:

Originally Posted by clifish

yes, I have the ECM

You can't meld the aftermarket with ECM, the advance will default.
But when you unplug an E4ME, it works as well as any 650CFM.
So change the carb, you need a non computer dizzy.
Will it run better? I haven't tried that (yet).

Feb 12, 2018 | 09:57 PM

Big2Bird

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The performer is almost the same as the stock 81.

Feb 12, 2018 | 10:25 PM

terry82

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From: columbia city in

I have changed a 1981 over to what you are doing .the guy was very happy after the swap.But he was having lots of problems with the factory carb.If your carb is working good ,I would not change it.If you can get the parts at a good price I would buy them .the factory parts are set up for a conservative fuel economy mode.The holley can be tuned any way you want .The aftermarket distributer can be set up for more advance .speedway has a good price on distributers,Cap ,coil and plug in about $70.00

Feb 13, 2018 | 05:17 AM

derekderek

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From: SW Florida.

So, the 81 is a q-jet with ecm controlled ignition advance curve? Do they use essentially a tbi ecm, or just a smaller ignition control module? I assume map sensor?