Are these modern carburetors a big improvement?

[PhotonFanatic]

Are modern carbs from Holley, Edelbrock, Demon, etc a big improvement over stock stuff from the 70's and 80's? One assumes there would be some improvements, but who knows. I'm hoping it's like a giant improvement.

The chatbot says they've basically eliminated the old cylinder wear problem. Where fuel wash would damage your block over time and it would have to be bored out eventually. Can anyone confirm that?

They also say electric choke is real nice. I never had that, and I had to put up with cold bloodedness.

Some of these modern carbs have had revisions in recent years. And some of them were even designed in 2008 and 2011. Can I expect some kind of better experience? Maybe better fuel economy, and better power?

 

[75gmck25]

Cylinder wear issues have been significantly reduced because most modern EFI systems keep AFR within very close limits. Modern carburetors are now usually better at keeping the mixture correct, but they still rely mostly on mechanical linkage and vacuum. They can often been tuned to have a EFI-like throttle response, but maintaining best AFR across all demands is still difficult.

It’s hard to make a blanket statement about modern carburetors, because the designs are much different across brands, but in general they are always being improved. For example, the Edelbrock 1406 is based on a very old design, but the Edelbrock AVS2 (or 1906) has tweaked the design by adding annular boosters and adjustable secondaries.

 

[legopnuematic]

In my opinion, no they are not.

A carburetor in its fundamental sense is using the same principles regardless of if it says Holley, Carter, Rochester, Edelbrock, Weber, Marvel, Zeinith, Demon, etc.

There are differences in how they might accomplish the same thing, like fuel enrichment, or how the secondaries work, but at the end of the day they still are working on the same theories and principles.

The difference is, what you can buy new today is a "universal" carb, meaning the MFG has no idea what it might end up on. Could be a Rotary, inline 6, 350, 440, 389, who knows. Whereas say a factory Quadrajet that came on a 350 new, was setup and calibrated for a 350ci engine.

Most people take one out of the box and maybe play with the mix screws, bump the idle screw, and that's it. A lot can be left on the table and most will just accept ok enough.

You can wash cylinders just as good with any carburetor, even tbi, or multi port injection if an excessive amount of fuel is entering the cylinders.

Electric chokes work fine, but so do a divorced or hot air or manual choke. Once again, it's up to the user to take the little time to adjust and tweak things in to get the choke to function as it should.

Power and mileage gains are once again up to the user, if one takes the time to set it up right, gets the timing setup correct with an appropriate curve, power and mileage should be good. Pop a 1406 on it from the auto parts store, depending on how bad it was before an improvement may be seen or may not be seen.

What I am getting at here is, if an engine runs poorly with carburetor "A," there is a likely chance it will still run poorly with carburetor "B." Same goes for putting fuel injection on an engine that doesn't run very well, it won't really fix it. Just like programming garbage in, garbage out, also remember, carbs are forgiving, ignition is not.

Also, just my opinion, I wouldn't trust AI for giving advice on really anything, or at least, to blindly trust it.

 

[TotalyHucked]

I'd agree with Spencer on this one. A carb is a carb, period. There's not much to improve upon vs years ago. My dad has spent time with both original 60s/70s carbs, 80s carbs and current carbs for various people over the years. In the end, they all ran very well, got great fuel mileage (all relative to the combo it's on of course) and had great drivability.

It has very little to do with the carb itself as long as it's in good, proper operating shape and has everything to do with who's doing the tuning and the combo it's on. The wrong carb is gonna be the wrong carb no matter what you do to it

 

[fast 99]

Carbs are stupid, meaning just mechanical. There was an experiment for a couple years with self adjusting carbs that had feedback. They were slightly more complex but if set up properly, worked. Even back then techs didn't know how to work in them.

Problem today is finding someone to work on carbs. Our shop doesn't even have a scope let alone an infrared. Older vehicles with ignition issues all we can do is best guess.

I haven't messed with any of the fuel injection conversion units but that might be the only way to increase fuel millage and engine life over a properly set up carb.

Engine masters had a few episodes using carbs with O2 sensors in every exhaust port. Overall mixture was never ideal. Some cylinders were rich others lean. It's inherent in the design.

 

[Rustisbest]

Unless you have a stock engine with the carb that came on it from the factory they all have to be tuned for the application. They only do what you tell em to.

 

[Finkaire]

Not available in California

 

[Ricko1966]

AI stuff you gotta dig deeper. A lot of the decrease in cylinder wear is better metallurgy,low tension rings,better understanding of rod ratios,cylinder wall clearances,better oils,and better mixture control. But it's not just mixture control. A Carbureated car and an injected car would have identical wear,performance and milage, if they both controlled fuel mixture equally well. Setting a carb up correctly will go a long ways towards these goals,buying one bolting it on and expecting it to be ideal out of the box,you have a better chance of buying the winning lottery ticket. At least half the people that bolt on brand xyz carbureator and rave about how much better it is,were comparing a new generic tune carbureator,to a worn out,dirty,misadjusted,carbureator that was in serious need of a rebuild. My brand new Nikes are so much more comfortable than my addidas,that have the soles wore out,insoles crushed and the sides stretched out.

 

[Turbo4whl]

My brand new Nikes are so much more comfortable than my addidas,that have the soles wore out,insoles crushed and the sides stretched out.

I like my vibram sole Merrell's!

 

[75gmck25]

One way to get carburetor working a little better is to install a wideband AFR gauge and use it to monitor the mixture. Then adjust and set it to keep it closer to the best AFR, which will vary based on the operating conditions at the time. For example, idle AFR might work best at near 14.7; lean cruise might give you best gas mileage at about 16.0-17.0, and when the secondaries kick in you might want it at 12.0 or lower. The challenge is to get all those mechanical settings working together and getting the AFR you want under multiple conditions.

 

[PhotonFanatic]

In my opinion, no they are not.

Also, just my opinion, I wouldn't trust AI for giving advice on really anything, or at least, to blindly trust it.

Well as Ricko says you typically have to dig deeper. While bearing in mind that it's only as good as it's training data, and they got that from large swathes of the internet. Even this forum may provide some of it's response, and that may very well produce a wrong answer... sometimes. If you only trained it on encyclopedia Britannica and it could only answer questions from what's found in the encyclopedia set, it would still only be 83% accurate. Cause iirc they found that a chunk of the data in those encyclopedias is wrong. Wikipedia ended up being slightly more accurate.

A dedicated mechanic Ai would be far better, if it was trained on every shop manual and parts manual. It would almost always be right, just like those medical ones that beat the smartest doctors really badly lol

But alas, perplexity is free.

One way to get carburetor working a little better is to install a wideband AFR gauge and use it to monitor the mixture. Then adjust and set it to keep it closer to the best AFR, which will vary based on the operating conditions at the time. For example, idle AFR might work best at near 14.7; lean cruise might give you best gas mileage at about 16.0-17.0, and when the secondaries kick in you might want it at 12.0 or lower. The challenge is to get all those mechanical settings working together and getting the AFR you want under multiple conditions.

So would that method be pretty much the end all, be all to getting a carb set up perfectly for the engine it's on? Cause what else is there really... You want the ideal AFR depending on how hard you're mashing the pedal. Then you just learn how that's done on the carb you have.

 

[Rustisbest]

You're not really perfecting anything with a carb or they would still be using them on factory vehicles. A wideband only gives you an average AFR on whatever side you have the sensor on. Some cylinders are rich and some are lean especially with a dual plane and that changes depending on throttle angle. Give the engine what it wants and use that AFR number for a reference if you need a gauge.. Otherwise look at the spark plugs. Cant just pull a number out of the sky like some do and wonder why it stumbles or runs like crap.

Theres a lot going on inside that can't be seen

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[ali_c20]

Are modern carbs from Holley, Edelbrock, Demon, etc a big improvement over stock stuff from the 70's and 80's? One assumes there would be some improvements, but who knows. I'm hoping it's like a giant improvement.

The chatbot says they've basically eliminated the old cylinder wear problem. Where fuel wash would damage your block over time and it would have to be bored out eventually. Can anyone confirm that?

They also say electric choke is real nice. I never had that, and I had to put up with cold bloodedness.

Some of these modern carbs have had revisions in recent years. And some of them were even designed in 2008 and 2011. Can I expect some kind of better experience? Maybe better fuel economy, and better power?

Annular boosters are a nice improvement and they were invented 50 or so years ago.
Electric choke is convenient.
Old or new carb it all depends on tuning it to fit your engine/needs as stated above.

 

[Ricko1966]

A lot of the fuel distribution problem is that the fuel is introduced at a kind of Central location and air and fuel has to travel to each cylinder, not the same distance not the same turns,so some cylinders will be lean or rich, this will also be true with a wet manifold fuel injection system. If the fuel injection uses the same manifold as a carbureator it will have the same problem

 

[PhotonFanatic]

A lot of the fuel distribution problem is that the fuel is introduced at a kind of Central location and air and fuel has to travel to each cylinder, not the same distance not the same turns,so some cylinders will be lean or rich, this will also be true with a wet manifold fuel injection system. If the fuel injection uses the same manifold as a carbureator it will have the same problem

It sounds as though the carb is fundamentally pretty darn limited and fuel injection should be used for greater accuracy and elimination of all those problems.

But what about that old mechanical fuel injection? Can't remember, but I think even back in the 50's there were some vehicles that used that system. They even had 1 injector per cylinder. I guess nobody makes that and you're not going to find it anywhere for sale.

"The oldest known vehicle to use port injection with one injector per cylinder was the brief production run of the Bendix Electrojector system, offered by Chrysler for the 1958 model year. This system featured fuel injectors mounted just above each intake valve and delivered timed pulses of fuel to each cylinder, meeting the definition of true multi-point or port injection."