carburetor for 1978

Fred A

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I have 1978 Chysler New Yorker which has been stored for awhile. 400 engine. The gas tank has been replaced and fuel filter. The carburetor seems not to function right. Are the rebuilt carburetors on ebay any good or is it better to buy a new carburetor? Or rebuid what I have. I see rebuild adverised on ebay for 229.
 
I have 1978 Chysler New Yorker which has been stored for awhile. 400 engine. The gas tank has been replaced and fuel filter. The carburetor seems not to function right. Are the rebuilt carburetors on ebay any good or is it better to buy a new carburetor? Or rebuid what I have. I see rebuild adverised on ebay for 229.
I would rebuild what you have. at least take it off and take the top off to look inside. If it is all corroded and nasty you might be better off buying a new carb if one is available.
 
I would pull your carb off and send it to @Dana He is the only person to provide me with a properly functioning thermoquad for a car @ayilar has me working on.
 
What carb is it.
2bbl Holley
Thermoquad, or ?
 
Personally, I highly suggest tossing your carb if it's the original TQ into the garbage. My personal experience and expensive battles with TQ's taught me it's not worth it. You can finally dial it perfectly on a Monday and by Wednesday it runs like ****.
I've been preaching forever to simply throw on an Edelbrock and it will run like a Swiss watch right out the box.
If you're really ambitious, go straight to an FI sniper.
 
IMO, There is no better carb than a properly tuned Thermoquad. My 78 440 powered truck ran the same TQ for over 500K and is still on it doing it's job. I replaced it with a Holley once when it was off for rebuild. I couldn't wait to get that TQ back.
 
Thermoquads were not all the same. In the later years, they had lots of "additions" which could be difficult to calibrate and such. I bought a 9801 TQuad for my '67 Newport 383 4bbl car. That particular part number aftermarket TQ was allegedly tuned for a '70 383 4bbl engine, which had the same cam as my engine (which already had 906 heads on it). Even with the Torker 383 intake, not very much difference compared to the OEM AFB and cast iron intake.

IF you like the look of a TQ, buy the Street Demon with the phenolic bowl. Inside, it looks just like the TQ it was patterned off of. Just need to get the throttle linkage adapter to make everything work. Watch the sales at Summit or Jegs.

Otherwise, an AVS2 would be my choice. Then head over to "318 will run" on YouTube and look at his modification of a Chrysler cast iron spreadbore intake so that a non-spreadbore carb will fit. EASIER than you might suspect! Then add the thick OEM carb gasket and you're done.

When the TQ came out, I was all for it. Some people had issues with leaking phenolic bowls, others did not. But as the emissions controls were added, things got flakier, it seemed. More "stuff" added as time progressed. Nothing really wrong, per se, but consider that it was not one of Chrysler's best fuel mixers, too. It was Carter's "last gasp", too, so not a really god end product, in many respects. The basic design MUST be good or Holley/Demon would not have copied it so closely!

In general, a new carb will be better than an older OEM carb. Reason? Additional tweaks and such to the primary venturi area which can increase throttle movement sensitivity. But are not apparent to the casual observer, but make things a bit better to drive. In THAT area, the TQ is still later 1960s technology (as the Rochester QuadraJet spreadbore came out in about 1965).

Several decisions.

Enjoy!
CBODY67
 
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Personally, I highly suggest tossing your carb if it's the original TQ into the garbage. My personal experience and expensive battles with TQ's taught me it's not worth it. You can finally dial it perfectly on a Monday and by Wednesday it runs like ****.
I've been preaching forever to simply throw on an Edelbrock and it will run like a Swiss watch right out the box.
If you're really ambitious, go straight to an FI sniper.
would this fit?

Edelbrock 1407 Performer 750 CFM Square Bore 4-Barrel Air Valve Secondary Manual Choke New Carburetor​

 
I have 1978 Chysler New Yorker which has been stored for awhile. 400 engine. The gas tank has been replaced and fuel filter. The carburetor seems not to function right. Are the rebuilt carburetors on ebay any good or is it better to buy a new carburetor? Or rebuid what I have. I see rebuild adverised on ebay for 229.
Does your car have the Lean Burn still functioning?
Or has it been swapped to electronic ignition But still using original Lean Burn carb??
Since the carb should be rebuilt by @Dana, may as well get him to modify it to work properly with electronic ignition, fatten the mixture from 18:1 to 14:1 ( bigger jets) and add a vacuum port for the vacuum advance for the distributor.
Brass floats if you can find them, typically from a 73 big block cop car application.

I love Thermoquads, but you have to understand their quirks to make them run right.
Dont expect a reman Thermoquad on ebay to work right out of the box.
Still need to set the metering rods and the spring for the secondaries to open.
Good luck and hope my 2 cents helps.
 
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