Ode to the Carburetor

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Once upon a time, there was a simple mechanical device that fed fuel to your car’s engine. It had no electrical hook-ups, was not dependent on sensors nor controlled by a computer. It was held in place by four bolts and could be physically removed from the engine in less than five minutes with basic hand tools. Its workings were visible – and so, comprehensible.carb lead

This miracle device is the carburetor.

You can still find them, too –  just not under the hood of any car built since the late 1980s. Lawnmower engines, weed whackers and other outdoor power equipment still use them. Probably not for long, though. And here we come to the why carburetors are no longer found under the hoods of new cars:

They are mechanical devices and cannot adjust themselves to deliver precisely the right amount of fuel (and air) to the engine under constantly varying conditions. This is a problem from both an emissions control and a fuel efficiency point-of-view. The carburetor is jetted to meter so much fuel to the engine. The jetting can be rich (more gas) or lean (less gas) but it cannot be both at the same time.

Nor in between.

The jets – small orifices through which the liquid gasoline flows – are a given size (diameter of the orifice) and that’s that. In some of the more sophisticated carburetors – like GM’s famous Rochester Quadrajet – the flow through these jets can be modulated by tapered metering rods that move up and down within the orifice, increasing (and decreasing) the amount of fuel that can flow through the jets. But the range of metering adjustment is mechanically limited; the extremely fine control possible with fuel injection is not possible with a carburetor.carb schematic

And there is another problem.

In a carburetor, liquid gasoline is pumped (via a mechanical fuel pump, usually) into a small holding tank called a fuel bowl inside the carburetor. Some of this fuel inevitably leaks into the engine, where it dilutes the oil – reducing its ability to lubricate internal parts and also shortening the useful life of the oil (necessitating more frequent oil and filter changes to avoid premature/excessive wear and tear).

Some of the fuel also leaks outside the engine – evaporating into the air.

These are evaporative emissions – and while the smell of gasoline in the morning is a fine thing indeed, it’s a big no-no these days. And it’s not a fixable issue with carburetors, because their design requires they be vented – open to the atmosphere.

Fuel sitting in the bowl is sucked through the carburetor’s jets by the vacuum of the running engine. Air is drawn through the carburetor and mixes with fuel; the resultant air-fuel charge is “inhaled” by the engine through an intake manifold (the thing the carburetor sits on) into the individual cylinders.tri power pic

In a fuel injected system, the fuel is injected under positive pressure into the engine. Modern system have injectors positioned directly ahead of each cylinder’s intake valve(s). Air is still “inhaled” by vacuum but it is not mixed with fuel until it reaches the cylinders.

The gas side of an FI system is effectively sealed; no raw (liquid) gas is present and so evaporative emissions are much lower. This was among the main reasons for the demise of the carburetor. Even if jetted perfectly, gas fumes are still going to escape into the air.

The Dude could abide this – but Uncle not so much.

Which is a shame. Because all cars now sound pretty much the same.

Intake-wise, at least.

There is still the hiss of vacuum. But the signature moan of a Quadrajet’s massive secondaries opening up when you floored the accelerator pedal is as much a thing of the past as the steam whistle. Fuel injection (especially port-fuel injection, which is what’s common these days) is all pretty much the same. Each cylinder has its injector, which sprays the fuel. There may be differences in capacity/pressure, but none of these are aesthetically meaningful. Whether you have injectors that flow 45 pounds of fuel per hour or 33 pounds of fuel per hour, you could never tell the difference by sound or feel.

Much less look.Hemi dual quad

Carburetors came as two and four barrels – and sometimes, you got more than one. Image three two barrel carburetors. Or two four barrels. Maybe a set of 45 pound per hour injectors flow more fuel. A dual-quad set-up still looks a lot better.

Sounds better, too.

But – most of all – a carburetor is involving. Making fine adjustments and tweaks; learning how the thing works – and learning how to work on it. An emotional bond is created; the satisfaction of knowing you fixed it. FI is mostly plug and play.

Which is probably why so few people play with cars anymore.

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83 COMMENTS

  1. Dear Eric [and interested readers]
    When I was young, I bought in 1961 from the original owner a 1947 Ford flat-head v-8 coupe, paid for by my Grandmother, and sold it in 1964, among the stupidest decisions in my life [or youthful inexperience].
    It had a HAND choke on the dashboard; never failed even on coldest Nashville winter mornings. I do not consider automatic chokes better, not even the mechanical one on my 1972 Dodge Dart.
    The 1947 Ford also had a HAND throttle for highway driving, a proto cruise control; but it could be dangerous. In hilly and curvy middle Tennessee then with almost no four-lane highway sections, it was best to let it alone.

    • Malcolm, I had a ’55 Chevy pickup with a Blue Flame six and a manual choke. It fired right up and idled as smoothly as what your ability to judge a manual choke would be. In other words, pull it all the way out and when it fired, depending on the temp, ease it in where you knew it would continue to run smoothly. It didn’t take long on that engine to reach a smooth idle with no choke.

      Back in the 70’s when carbs had to do double duty with the smog crap put on them, many of us returned to manual chokes. I’ve seen lots of 60’s and 70’s cars and pickups with aftermarket manual chokes.

  2. I like carbs and got satisfaction adjusting them. However, living in Canada, you find out things like automatic chokes don’t work that well in the winter. You’d start the car and hop out to scrape the windows. Pretty soon the car was running rough and about to stop so you dashed over to the driver’s side, through open the door and hoped you got your foot on the gas in time. Typically, you now had to keep your foot on the gas for a couple minutes to keep it running. Then, back out to finish scraping.

    First car we owned that had fuel injection was a new 1988 Olds Delta 88. Beautiful car and never had any cold weather issues with engines running rough or quitting while you scraped. Engine just purred along.

    Still like the carbs but wouldn’t give up FI.

  3. I used to drive a ’68 Saab 96, in Baltimore. One winter I got some water in the gas. The fuel line froze. PITA in the morning – hope for sun, open the hood, use a hair dryer and trouble light – 2 hours later the carb works. I realized that removing the carb was easy (2 bolts, hose clamp for fuel intake, throttle linkage, 2 hose clamps for automatic choke), so I just took off the carb in the evening, stored it inside, reinstalled it in the morning. After doing this for a week, the water was gone.

  4. For years I drove a ’78 C-10 with a Q-jet. I bought it from a junk yard in the early ’90’s, and it had a 305 with a thrown rod. I bought a 350 for it and I rebuilt the engine including the Q-jet. It got bored .10 over, flat top pistons, Competition Cams RV cam, Weiand 2P 180 High Rise Intake manifold, and headers. The heads were shaved and had a 3 angle valve job, and I ported it. I also beefed up the HEI, and I installed a Q-jet kit from Brad Urbans Carburetor Shop. I later wished that I had bought the same Crane Fireball Cam 280/460 that I had bought when I built a V-8 Vega years earlier, but my oh my that truck sounded sweet when you floored it! I could hear that WAHHHHH from the carb in the front and the 12 inch glass packs talking loudly in the rear. That truck only got 10 mpg though, loaded or empty. An overdrive tranny would have helped.

    • I’m also a fan of Weiand intakes and have close to the same one you speak of on hand. I have a new Comp Cam I never used. Instead I had a custom Lunati ground, best all around cam I ever used. Funny that the hottest cam I ever used was a Chevy cam and the best performance carb I ever had was a Holley with a GM parts #. Nobody would touch one for a rebuild so I did it myself. It had a lot more parts than a conventional Holley but started up and idled fine cold. Your engine building sounds a great deal like mine.

  5. Hello, Eeic,
    The Holley 1920 Model [one barrel ,Two mounting bolts] on my 1972 Dodge Dart 225 c. i. 6 cylinder has always run smoothly and started quick, very cold and very hot weather. I bought the car new, and ordered, in Nashville. To each his own, but I much prefer that car to any post-1979 car. Two regrets: 1) I did not have factory air installed [$400, and I did not need it at that cost], and 2) the quality of carburetor kits is down, like points, hard to find first quality ones. In 1976 I bought a second-hand 1970 Dart, 198 engine. It had a Ball & Ball Carter carb. It was problem-free, but more bothersome to rebuild compared to the Holley. They were actually inter-changeable on those engines.

  6. The daily gofer car is another old Peugeot 405 SR. This one has a manual transmission, 1905cc two valve per cylinder, sohc four cylinder engine. It is a sedan- remember those? They have a boot (trunk) with a nice structure separating the luggage compartment from the passengers, adding torsional rigidity to the body so the car can handle. Anyway, this car has a single two-barrel Stromberg carburetor.

    Now here is the fun. This fine example only has a titanic ~115bhp at the flywheel, but it does have sharp and finely accurate throttle response and it likes revs- screams it guts out at every opportunity. It sounds amazing. Also the over-run is cool, as it backfires and snuffles down ready for the next thrash.

    Why does this simple car make driving so enjoyable? Well, I think it is down to several things. It always starts first time. It uses modest amounts of fuel (a lot less than a traditional six would). It has astonishing road holding and excellent handling with instant response, no mushy lost motion, bright feedback and little phase delay. It has low weight (which is a major part of its secret). It sounds absolutely brilliant. You’d think it had got lost on the way to a rally stage somewhere (and THAT is how it is best driven, like it is on a stage). It is exciting, fun and has character (while not being as hard case as a 205 GTi or a 306 GTi6 – those two are outstanding cars and starting to get expensive to find). THAT is the point right there- character. You need it in everything you drive as a #1 antidote to the bland sameness that is oozing up everywhere around us in this life.

    BTW, the carb just got its rebuilt for its 22nd birthday. It takes four bolts to get it off the manifold and then there are some coolant hoses, a wire (for the auto-choke IIRC), throttle cable and intake hose to remove. Then it went to the kitchen table and got rebuilt. Then back on the car. The kids enjoyed the project and were able to take part in it.

    Interesting point. The next car up the range is the 405 SRi, which has fuel injection and another 10 hp. Sounds quite different. Different character.

    Important point. While my 405 SR sounds really good, it is NOT loud. There is a lesson in that. I think Peugeot at the time had people who really understood about driving.

    A fortnight ago I went over to the wrecker and helped myself to a few extra carbs- just in case. He thought he was doing well when he charged me $35.00 to quit the lot. I like how that worked out -both parties very pleased with the day’s effort.

    Hail to the might carb!

    Si

  7. Fuel injection on small engines is already here, has been for years, go look at the Robins/Subaru engine on one of the pressure washers at the home depot it has an injector block in place of carb. And I met one of Echo’s top engineers and he said there engines have been designed to work with injectors when EPA regs determine that carbs will no longer be clean enough. I liked SU carbs myself, simple to work on very reliable.

  8. Motorcycles are going the way of autos, most of them now equipped with fuel injection, ABS, and increasingly, traction control. But the Kawasaki KLR650, a living relic of 1980s design, is still equipped with a Keihin carburetor for its single “thumper” cylinder.

    Carbs are good for serviceability in remote areas and the developing world. They aren’t quite as good for fuel economy on a bike, where fuel capacity is limited and range is important.

    Anyhow, the KLR650 may end up being the last carbureted street vehicle sold in the U.S.

  9. A minor correction, which isn’t just pedantic as you really have to understand this in order to “get” a carburetor: fuel is NOT “sucked through the carburetor’s jets by the vacuum of the running engine”. Instead, the vacuum is created by air flow through a venturi. The higher the air flow, the lower the pressure at the venturi. It may not be intuitively obvious, but intake manifold pressure actually increases (another way of saying that vacuum decreases) with engine speed. It’s more understandable when you think about it in terms of there being “less vacuum” when the throttle plates are more open.

    Engine vacuum does pull extra fuel in when the choke is closed, however. Cold gasoline running through the intake manifold into the cylinders on a winter morning probably caused more emissions and engine wear than at any other time.

    Incidentally, my 1970 429 Torino CobraJet had a QuadraJet. As far as I know, this was the only Ford that came from the factory with a Rochester carb. I probably spent more time dicking with that carb and adjusting the dual points than I did actually driving that car. When you put your foot in it, you could literally watch the fuel gauge dropping.

    • And of all the Fords I drove and worked on, I considered the 429 the best engine they ever produced. I never had one with a Qjet but it would have been an improvement over the other carbs, mainly two barrel Holley’s.

      Not many people knew that Qjets for BB’s had a few models with leaking freeze plugs. You could removed the top half, pound on the lead plugs and fix the leak. Some even removed the lead and put JB Weld.

  10. I think the carb was the worst mechanical device ever put on an engine. it was as unpredictable as the worse woman you ever knew. in every different weather scene it would or would not idle right. cold and damp pull over raise the idle. stupid auto choke made them worse. never worked right always adjusting it. hand choke made carbs workable. on small equipment carbs a disaster. fuel injection 6 billion times better. throttle body on my trucks was in between a carb and injection they worked very well

    • I don’t know about that. I didn’t like carbs myself, but I nominate today’s Variable Valve Timing cam phasers. They are finikey and cost a fortune to replace.

    • Hi Mr Meener,

      If properly adjusted and correct for the application, a carburetor can work extremely well. But note the italics. It takes a person who knows what they’re doing to properly adjust a carburetor – and that’s hard to find (especially today).

      I swear on a stack of SD-455 connecting rods that my Trans-Am (with a Rochester Quadrajet) performs comparably to a modern car. But in some ways, better. The sound of a four barrel opening up is like the high point of Wagner’s Tannhauser – and because each carb makes its own sound, it helped to define the engine and the car. Today’s PFI engines pretty much all sounds the same, at least on the intake side!

      • eric, the first TBI’s sounded like a QJ if you turned the filter cover upside down. I was pleasantly surprised the first time I drove a 350 TBI pickup and the owner had turned his cleaner lid upside down…….waaaaaaa

        Just a glance at an ’88 and you’d never have known it was TBI.

      • eric, you gotta wonder if the QJ on the 429 conversation didn’t go something like this. Say guys, everybody complains about out cold starts and says the GM QJ fires up and idles fine and you just drive away. Yeah, but we don’t know of a carb on anything else that works that well and we can’t just rip off Rocherster’s design. What to do, what to do. Say, a 427 Chevy and the 429 are close enough. That’s right, we’ll just buy the same one off Rochester, problem solved.

        The rub came in when the 429 didn’t flow as well as the 427.

    • worked in automotive, marine, and heavy equipment for thirty years….. I ever did find a carburetter as finicky as what you describe. Set them up properly they work almosst indefinitely. Never an issue. Now, there were many other factors that could fool one into thinking it was a fuel feed issue….. which, once found and dealt the fatal blow, were a relatively permanent fix.
      Worst case I ever encountered was in a late sixties Mercedes 250 S, six cylinder single cam twin twin choke (progressive) Stromburgs. Had a frequent but not totally consistent bearkdown in fuel flow to the engine at midrange throtttle settings. Nasty to drive. After four trips through the pair, which were quite clean when I got into it first time, I finally got mad and yanked out the small brass blocks that carried the emulsion tubes for the primary throats…. there, at the bottom of that emulsion tube, and sticking out the even smaller jet at the bottom, were a number of brright red threads….. obviously from a cheap cotton shop towell. I can only surmise the former owner had done a carb rebuild and used compressed air to blow dry everything…. using the cotton shop rags to hold each bit as he blew high pressure air into it. Fine needle nose pliers yanked out the red fibres, car ran perfectly once found. I was near ready to try and find a used pair of instruments……

      Once finished, the new owner drove that car trouble free for many years. It was a classy ride down in So Cal back then…. some thirty years old, looked and ran like new, had plenty of snoose, and when the twin exhaust started singing at high RPM it made a very sweet sound. As I recall that heavy luxury sedan (four door, hide seats, gorgeous wood fascia, plush carpet, etc) returned high 30’s in miles per gallon.

  11. Eric,

    To engage the Clover is like wrestling with a pig. When you wrestle with a pig you both get covered in shit and the pig likes it.

    • I use a couple 60 Series Detroit’s, each with it’s own little “off” for a split second. It won’t come back without lifting completely and then back down to the floor. I only know it’s reset when I hear the turbo spool up, music to my ears for sure. I detest a slow boost tube since it takes longer to vent and longer to change gears while you lose speed.

  12. Clovers / Pakleds don’t owe anyone anything more than to observe the NAP. All they need do is stop violently intruding into other peoples lives and we could all leave in peace.

    If you’re able to trick a superior person into helping you by claiming you “need things to make you go.” Then good for you. As long as your enablers help you voluntarily, you are free to do as you please.

    You need not be honest. Nor nice. Nor mannered. You need not answer anyone. You need not be forthright or equitable or really anything really. Sling your incoherent insults at your betters to your hearts content, if that’s what you enjoy doing.

    Perhaps there will always be a niche for Pakleds and Clovers playing the victim and tugging on a good persons heartstrings until there once again on their way across the universe. To boldly go where no one as incompetent as they are should ever have been able to go.

    • Tor the government did not do anything violently to me. What did they do to you? Did they deck you and then kick the stuffing out of you? Well good for you Tor.Clover

      • Clover,

        Every law carries with it the threat of violence for noncompliance. You are arguing that because you choose to obey like the good Clover that you are, “the government did not do anything violently to me.”

        Just obey – and no violence will be done to you. That is your argument. You remind me of the character Parsons in Orwell’s 1984. He obeyed. He loved Big Brother. And yet, one day, they came for him, too.

        Maybe they never will come for you.

        But the fact is, you’ve been threatened. That is violence. You merely choose to pretend otherwise, because you obey – and so avoid the violence.

        But the threat is always there.

        • CloverShow me Eric what I have to do against the government for them to beat the stuffing out of me Eric? I can not think of a single law that will do that barring pulling a gun on someone or starting a fight. Enlighten me with your brilliance Eric. If the government has not and will not ever threaten me or my family or friends with violence then tell me why I should care about your statements? Why should I care about your paranoia?

          • Clover,

            Every law carries with it the threat of violence for noncompliance. You are arguing that because you choose to obey like the good Clover that you are, “the government did not do anything violently to me.”

            Just obey – and no violence will be done to you. That is your argument. You remind me of the character Parsons in Orwell’s 1984. He obeyed. He loved Big Brother. And yet, one day, they came for him, too.

            Maybe they never will come for you.

            But the fact is, you’ve been threatened. That is violence. You merely choose to pretend otherwise, because you obey – and so avoid the violence.

            But the threat is always there.

            • Eric you are 100% correct !
              The wonderful mind that was Mark Twain stated very clear:

              our life , body integrity , possession and rights are assured and not in danger only when our government and Parliament is going in Holiday !
              For the rest of the year look carefully around you and run for your life because we are defenseless !
              Today it is worst then in the time of Mark Twain ! Do you !
              Therefore I would like to appreciate very high your standing position about this subject !

          • Clover, you want to be beaten? Ignore a cop, just ignore him when he commands you to do something. Just go about your day like he wasn’t even there.

            • Fork Clover. Every time one of y’all responds to him, you’re giving him what he wants. Remember Mark Twain’s observation that when you argue with a fool, an observer can’t tell which is the fool.

              Ferkin’ clover has been made into an icon here. This makes no sense to me whatsoever.

                  • I said that years ago. Clover takes me to task for something I say and I simply don’t respond. He recently replied to my comment about a QJ and the noise it makes. It makes that noise because it’s supply air. clover stated it was the same as dumping 5 gallons of gas into the engine. I responded by not responding. Stupid shit she is….has no understanding of anything, not any thing mechanical, simply anything. clover….KMA

        • but the obedience IS the violence done to us…. when coerced by actual or threatened violence to do as we would not otherwise do.

        • Clover’s in a feedback loop.

          Obey – and the system does you no violence. Because you’ve obeyed, no violence is done.

          Clover is incapable of understanding what duress means. Or he’s just too dishonest to acknowledge the fact.

          Clover does not feel himself threatened or controlled because he accepts the morality of obedience. If a law is passed, it must be obeyed. Because, after all, it is the law!

          If a legal process is used to take your money, force you to do something you’d otherwise not do, then (as Clover sees it) you have no legitimate reason for not obeying.

          Thus, while he probably would not take $10 out of your wallet himself – and would object if you took $10 out of his wallet – he will rise up in a rictus of rage if you “cheat” the government out of what it arbitrarily decides to take from you.

          The Clover mind is compartmentalized, incapable of conceptual thought.

  13. Despite the “aesthetically meaningful moaning” of a quad carb, I don’t miss those things one bit!

    The advent of EFI brought an end to over 90% of all hard starting, rough running, and sudden stalling issues.

    Carburetors……vinyl covered roofs….”wire wheel” hubcaps……Opera Lights…….AMF to them all.

    • Just poor tuning, Mike!

      Seriously. My ’76 TA starts immediately; never stalls and now that I have adequate fuel flow, never bogs, either!

      • No question that someone like you, with the tools, time and training, plus a passion for tinkering with things mechanical, can make a carb run well. But you are far from the everyday driver.

        Unless one really enjoys playing with carburetors, they are a PIA.

        • My ’76 Chevy never started hard either, and it was parked outside 98% (at college) of the time. Always started up no matter how cold it was, and on days cars with FI wouldn’t start.

          It didn’t stall after the too small exhaust system was up sized to the proper size. It wasn’t the carb, that made it stall, it was being suffocated by the exhaust and the badly engineered 70′ era catalytic converter.

          None of this stuff is hard, I am not very handy with cars, then and now. You really only need a screw driver for the most part.

          • We had a ’77 Silverado and a ’77 El Camino. With identical engines performance was very similar. I swear, both of them would suck the hood in when you stood in them. WAAAAAHHHHHHHH!

            We were working on big rigs last week and got to talking about those old vehicles. I mentioned how the QJ had that badass sound and another guy said (Yeah, put your foot in it and it was WAAHHHH!). We all laughed except for the young crowd. They sorta get it but don’t recall the vibration cleaning your teeth. WAAAAAHHHHHHH…..sonic tooth care.

            • Yes Eight and it was just like taking a 5 gallon gas can dumping it into the carburetor. I will take my 35 to 40 mpg over that WAAAAAHHHHHHH sound any day. The new cars run for 100 thousand miles without touching them other than a few oil changes every 10 thousand miles or so. The old WAAAAAHHHHHHH cars oil looked worse after 1,000 miles than a new car does after 10,000 miles. The new car you just turn the key at 30 below zero and it starts right up without getting the tools out. Not the old WAAAAAHHHHHHH cars. They would cough and sputter and spit and bang and that is if they would run at all.
              I will take the cars built the past 20 years over those any day.Clover

              • clover, not all old cars were dirty and that Qjet delivered a very precise amount of fuel. If your two barrel carb got soso fuel mileage, the change to a Qjet got you several more mpg. But let’s not let facts get in the way.

                Of course you could always install a Holley 3 barrel on an SBC and give it half again as much gasoline as it could use but most people knew better.

                One thing a Qjet did not do was cough, sputter, spit nor bang. Rarely does an engine bang more than once. You must have driven those Ford two barrel Holleys that required multiple starting and replacement a year or two into their life.

                I don’t know how to break it to you but an ICE is, for all practical purposes, an air compressor designed to make it’s own power with fuel. Even which ever engine you think you like.

                  • Yes Eric the good old days. In your own words you said that you needed to replace your transmission in your old car to save a few rpms so that you do not have to rebuild the engine multiple times. Eric the modern engines run for hundreds of thousands of miles without rebuilding. Eric I have better things to do then rebuilding engines every few years. I usually keep my cars for well over 200,000 miles the past couple of decades and have yet to need a rebuild and no one that I know has had to have a rebuild of engine or carburetor. Eric you can have the good old days if the most fun you can have is get your hands greasy. Go and get your 10 dollar an hour job pulling wrenches. Maybe it will be a step up for you.Clover

                    • Clover,

                      At least “pulling” (you probably meant turning) wrenches is honest work. Unlike the “work” you do (or did) as an insurance mafiosi.

                      PS: I’ve explained why I installed (not rebuilt) a new transmission in my car. I installed an overdrive transmission, in order to reduce engine RPMs at highway speed. A mechanical illiterate such as yourself does not grok such things, of course.

                      Serious question, Clover: Do you know how to do anything? I mean, other than compose ungrammatical, ill-informed and poorly constructed posts online?

                    • Yes Eric I know how to “pull” on wrenches and “turn” a screw driver. It is obvious that you do not know how. Anyway, I prefer not to spend all my waking hours pulling on wrenches. I have a lot better hobbies than that. Clover

                      It was you that said one of the reason to decrease your engine rpms was so that you do not have to rebuild it because parts are limited. That was your words not mine. If you do not believe me then you look up what you said.

                    • Clover,

                      Well, I know that one turns wrenches. And – unlike you – I’ve proved that I know how to turn them.

                      All we know for sure about you is that you have trouble with grammar and usage, resort to personal attacks when you’ve not got facts to support an opinion you hold… und so weiter.

                    • Clover,

                      When you provide some evidence that you’ve ever turned a wrench in your life, I’ll take more notice of your usage assertions.

                      Poor ol’ Clover!

                    • PS: Which insurance mafia did you work for? Was it the Progressive “family”?

                      Or perhaps the Geico “family”?

                    • OK Eric. You are superior. How many years of home schooling did it take for you to learn how to pull on a wrench? You are a joke. Pooor Eric. When does your 10 dollar an hour job of pulling on wrenches start?Clover

                    • Clover,

                      Wrenches rotate – hence turning them. To pull on something means to draw it toward you. One does not pull on wrenches.

                      Regardless, I do know how to use them. Have demonstrated that I do. I also know how to write – and have demonstrated that as well.

                      What have you done?

                      Heck, you have trouble putting together a simple, grammatically correct sentence! And – as far as we know – you don’t even know how to check oil level, much less anything more involved.

                      As regards the rest: Whatever job I have, it’s honest work. What I earn comes to me from people who freely consent to pay me.

                      Where does the money you have come from, Clover?

                      I’d be willing to bet $20 (real money, which I’d actually pay… unlike the “million dollars” you constantly bet but then never pay) that you work (or worked) for the government or the insurance mafia, both of which take money from people using threats.

                      C’mon, Clover.

                      Prove me wrong – and I’ll send you $20 today!

                      But you won’t. Because you’re a fraud – and a troll.

                      Your next post will be a cavalcade of insults and unsupported assertions; you will change the subject; you will erect straw men arguments. You will demand “details” that have already been provided, numerous times. But what you’ll never do is back up anything you “say” with other than your feelings.

                      It’s too easy, really.

                      The problem is there are just too damned many of you. And – per Marshall Zhukov – quantity has a quality of its own.

                      Unfortunately.

                    • Clover,

                      “OK Eric. You are superior.”

                      Well, yes. Certainly as a writer. That much is obvious. As a mechanic and driver, too.

                      But I am much more proud of being morally superior to you.

                      I reject using force or its threat as the basis of my interactions with other human beings.

                      You embrace it (without being man enough to openly say so).

                • I know a lot of people don’t like them but I do like the computer controlled Qjet. Basically the computer takes over mixture control and that’s about it. The result is a simpler more reliable carb that adjusts itself, not requiring manual adjustments for altitude or the season.

                  • I had a 1984.5 Nissan 2.4L pickup with a computer controlled carb. It was a nightmare in cold. It made no difference if you put fuel additive in it to address a possible water in fuel situation or what your or anyone elses guess was as to the problem. Below 20 degrees it worked as long as it was WOT but literally bucked, hissed and spit back through the carb although it didn’t backfire at anything less. Oh well, the old 350 or 454 would start, idle and run just fine and keep the ice off the windshield too, another failing of the Nissan. I’d use alcohol and Windex both in the windshield reservoir to try to keep the ice from building on the windshield.

              • “…if they would run at all…” That’s funny, had an old P.O.S. Ford F150 (Autolite carb) that would start easily when nothing else would – including our 1995-2008 EFI gas and diesel powered equipment. My 85 Cutlass (electronic Q-Jet) fired right up at -17 F ambient (-76 F factoring the wind chill), and I was really hoping it wouldn’t – not fun to do wireline coring in that cold. My TBI 2.5L Chevy Celebrity wouldn’t even think of starting in that weather. My ’95 corolla got real tempermental in extreme cold too….

          • Acquaintance of mine gained a second and a half on his 1/4 mile ET by dumping the stock exhaust for headers and duals on his early 70s Chevy P.U.
            Pretty scary that the stock stuff was that bad…

        • The beauty of a Quadrajet is that it rarely needs tinkering to make it feed well. They run and run and run very well needing only an occasional rebuild gasket kit…typically around ten or eleven bucks, and straightforward easy to install…even for a neophyte. Messing with the tapered secondary metering rods requires a bit more know how to get it right. And, I too loved the growl and performance gain as those big secondaries opened up and gave me a kick in the butt. The only reason the Rochester Q-jet wasn’t a popular hotrod racing carb is because the primary jetting was internal and couldn’t be changed quickly between races if necessary due to ambient temperature and pressure conditions

        • I live in an area of the country whose autumns and springs would freeze most Americans to the marrow, not to mention our winters. My cars started and ran fine and I had to have a car carburetor rebuilt just once. My old Rambler with the 327 V8 always started even without a block heater and me running summer weight oil in the winter (remember when you were supposed to change to winter weight oils?)

          You could screw up carbs, but a little knowledge and a very modest tool set were all you needed to tune them. I get the impression that many EFI lovers today are pretty much ignorant of how reliable carbs were and rely on urban myths for information.

        • “Unless one really enjoys playing with carburetors, they are a PIA.”

          Agreed. Another PITA is points. Pertronics is a great replacement for points in an older engine.

      • We used to vaca in the NM mountains, sometimes Tx. First thing I’d do upon arrival, even before peeing(not always)was to pop the hood, use my handy dandy long screwdriver and tune the carb(lean it). Next morning everybody from Tx would be out there trying to keep even Quadrajet’s running although they would, just with lots of unburnt fuel. I’d get in mine, give it a quick twist and instant perfect running. Often people would look at me taking the air cleaner off and fiddling with the car as if I had some POS problem but not all. Every now and then somebody would say “I guess I should do that too but not sure I’d get it right”. I’ve volunteered right then to do the same to theirs and show them where it was and where I turned it to so they could turn it back when they got back to the lowlands. Craftsman always had a long #1 slot blade screwdriver in their sets that worked well for this.

        Every now and then a woman would say “Hon, you need to pay attention so you can do what this young man can”. There’s been some priceless looks over this.

      • I drive a ’55 Chevy dually every day. It has a one barrel carb and an oil bath air filter. A little choke on cold mornings it starts just fine. Warm it up and you don’t have any problems. The “huzzah for everything new” banter is the rally cry for the dumb and/or lazy.

  14. I miss old carburetors meant to be repaired and rebuilt. The new ones are garbage that corrode, clog and fail from water and ethanol contaminated gasoline. They have few replaceable parts, parts are stamped and pressed and sealed so attempting to even thoroughly clean them often destroys them. I suppose it is just a matter of time before the simple push mower becomes fuel injected.

    Carburetors are universally misunderstood and blamed for every performance malfunction. Few mechanics bother learning the physics involved for their proper operation. Many carburetors were hopelessly mangled when the real problems were vacuum leaks, clogged filters, faulty ignition and low compression.

    • “Carburetors are universally misunderstood…”, amen to that. I’ve repaired more than a few carbs and it never ceases to amaze me what some people will do to “fix” one. One self proclaimed carb guru I know would just twist the idle mix screws around and call it tuned – LMAO clueless MF’er. Poking holes in the diaphram (holley v.s.) to slow the secondary opening rate after removing the checkball from the vac passage, who would believe it had a lean bog (sarc)? Guess he never heard of a spring/quick change kit…

      • Hi DirtyB!

        A properly set up carburetor is a beautiful thing. The slight adjustments/tweaks are, to me, fun – part of the experience. What fun is there with FI? Just install the injectors, run the wires and the ECU runs the show.

        I love getting the secondary air door tension just right. Playing with jet/metering rod combos. Most recently, I had a WOT throttle partial lean-out issue that I traced to the bowl running empty (a Quadrajet weakness in high horsepower applications). A 1.45 needle and seat assembly cured that, along with some piddling with the float level.

        • I like the simplicity of a carbed setup. A stock (for it’s intended application) carb in a stock vehicle is IMHO very easy to maintain. I also think that a carb is easier (and less expensive) to tune once you deviate from stock applications.
          EFI has plenty adjustments/tweaks available (especially once you get away from a stock drivetrain) but tuning and data logging software, wideband O2 sensor(s), and a laptop start to add up the $$$. Now factor in that no one tuner seems to support all vehicles and it seems to me that your wallet might be happier if you ripped out all the factory crap and installed a megasquirt system (if it must be fuel injected) – OR just put a carb on it 🙂
          Speaking of carb tuning, you probaly already know that it is best done at the dragstrip (hint hint), be sure to post your timeslips too ;P

          • Pre-emission carburetors are pretty simple to keep in adjustment and to rebuild when the time comes, at least the ones on typical grocery-getters of the day.

            The later emission-control carbs can be a nightmare though like the electronic feedback monstrosities found on 1980s AMC and Jeep vehicles.

            • I had pretty much forgotten the nightmare of the feedback carbs, selective memory I guess.
              Had one on a mid 80’s cutlass that ran well enough (all stock) until the computer pooped out. When that happened it ran like I had a tank of bad fuel except at WOT, where it was fine. Computer only controlled the part throttle mix on that particular Q-Jet.
              Ever looked at the vacuum hose layout on an early 80’s carbed Accord? Kinda looked like someone ran 4 octopi through the dryer on high heat.

            • Hi Jason,

              I’ve worked on most of them at one time or another. Holleys are incredibly simple – which is their weakness. They are fantastic “all out” (high performance) carbs but their choke/transition circuits are primitive and the unit lacks the fine-tune capability of the Quadrajet which – my opinion – is the best automotive carburetor for street use ever designed.

              People are often intimidated by it because it has a lot of small parts and there are “tricks” you have to master in order to to work on one successfully (e.g., learning how to reinstall the air horn without damaging the primary metering rod assembly; adjusting the secondary air flap tension correctly) but once you understand its workings, you begin to appreciate the engineering genius behind it.

              Properly setup, you can get operational characteristics out of it (near-immediate cold starts; sharp throttle response without any hesitation or lag) that are very close to a modern PFI system.

              • I used to agree with that. The quadrajet does work really well on street and mildly modified cars. I never liked the holleys as requiring too much maintenance.

                But last year when I stuck a 351W in an old rusty CJ5 i put a Autolite 4100 on it which I just couldn’t make run right. Then I picked up a Holley 4160 (I have a stack of about 25 Holleys I’ve picked up over the years at auctions and rubbish sales for 2-10 bucks).

                That manual choke 4160 made a fire breathing, screaming moaning monster out of that 351. And I started studying the Holley and how heavily built and precision it is compared to the Rochesters and Carters (now Edelbrocks).

                I’d have to say that in the hands of a capable owner the Holley is a fine piece of equipment. Vacuum secondary of course. Not to dis the Q Jet, but there is more to the story.

                And the only real objection I ever had to EFI was that you couldn’t get inside and tweak it. I’m going to try out a DIY megasquirt later this winter- but you’re right even the DIY megasquirt is going to set me back $500 easily by the time I’m done.

                PS- as far as sound, looks, and cool factor goes I’ve never found anything to compare to the dual AFB’s on my old man’s 425 GS Riviera. Really boggy on the bottom, but you can almost hear the gas gurgling in as you rev up from 50 to wherever the top is. I’ve never had the nerve to find it!

                • “And I started studying the Holley and how heavily built and precision it is compared to the Rochesters and Carters (now Edelbrocks).”

                  Yep, you got two kindsa carbs: Holleys, and all that other shit that ends up in the brass barrel.

          • Hi Bob,

            Carbs are much less expensive than EFI, even simple TBI systems. Also, much more durable. My Trans-Am has its original Q-Jet. It is 40 years old. How many FI systems will last 40 years? And – assuming I do not croak and the car remains in my possession – the Q-Jet will still be feeding the TA fuel in 20 years’ time.

            I’ve rebuilt it a couple of times, it’s true. But that involves a $70 kit and about an hour of garage time.

            Even if you have to start from scratch, a new Edelbrok QJet is about $450 and a new 4BBL intake about $150. That comprises the entirety of the fuel delivery system. A basic TBI system (last time I checked) cost about twice as much at least. And if you are talking about a modern car, you are talking about the ECU to go with it, plus a bunch of sensors on top of that.

            Feed it fish heads!

            • Hi Eric,

              Another plus for old carburated vehicles, in the event of an EMP, all the new stuff not sitting in a Faraday cage will be history. Of course, at that point, having a running vehicle would not be enough to overcome the failure of other infrastructure. BTW, is this Clover dude the infamous Gil? He trolls other interesting sites like the Daily Bell in the comment sections and is equally incoherent there. Meanwhile, I think I’ll go adjust a carb for Jesus…

        • And float level is a big part of it to be sure. Vacuum secondaries on high CR engines that would rev quickly could even be sped up on a Holley by wiring it together to get instant secondaries. It worked better on GM part # performance Holley’s that I preferred to the regular model. Most people avoided them like the plague saying they were too complicated. I thought the regular performance Holley was a bit too simple. You could get good mileage from the GM models but not so with the plain old out of the box Holley. Of course most people would stick a 900CFM on a SBC and wonder why it ran so much better as a QJ. They couldn’t understand 650-680 CFM are often all a small engine needs and the bigger carbs just kill them. I bought one of those Econo-Holley’s once. What a POS that ate gas like there was no end and performed quite badly compared to a QJ.

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