Do not fear the impending woes of the world coming to an end due to arachnophobia, especially when these multi legged creatures are made from vintage watch parts. These mechanical marvels are made by a jeweler in Chicago by the name of Justin Gershon-Gates. The objects he creates all stem from vintage mechanical parts and these mechanical bugs are an offshoot of his day to day operations. Check out this post and more original creative concepts at This Is Colossal "Chicago-based jeweler Justin Gershenson-Gates recently grew a bit tired of creating jewelry after a show this summer and while experimenting with some watch part anatomy he decided to try his hand at spider and insect legs. One thing led to another a new series of small sculptural arthropods and insects was born. Justin tells me via email that each piece takes several hours to make and being unable to leave things unfinished he generally makes an entire new creature in one sitting, a monumental feat considering the scorpions can take an entire 12-hour work session as the watch springs, stems, gears and straps are assembled and soldered together (nothing is glued). I love the idea of the tiny light bulb for the spider abdomens. If you’d like to see these crawly pieces up-close, you can see a few at the Bucktown Holiday Art Show December 8th and 9th, and you can also pick up some of the spiders on Etsy, at least for the moment. Tons more photos on Facebook. (via neatorama)"
Using the new tools of the internet enjoys us to no end, but in the process as a nation of builders, are we losing our sense of how to do things by hand? The do it yourself mantra is one that we hope this nation never loses. As jobs and career paths move in different directions using new technology, losing hard fought skill sets and basic mechanical knowledge could be our ultimate downfall. A nation that cannot build and sustain its infrastructure is losing all footing for its base to grow.
Mark Cuban recently expressed his thoughts about the next big debacle of financial crisis in defaulting student loans, check it out here. What really got us thinking on this more than anything is not about how many folks go to college but what are they learning and how it relates to a solid career path.
When plying in a trade, you are taught all the facets of that particular job and in the actual job setting. Every day is continual growth as you learn more about the job at hand and your pay is directly tethered to your experience and drive to succeed. College on the other hand is teaching you how to learn about learning. There is inherently nothing wrong with that equation as knowledge is power. But, on the other hand, many more individuals are seeking out college instead of a pliable trade in which a solid future could be more within their grasp.
Have a look at these graphics below, from some years back talking on the decline and rise of jobs. Even though the information is a bit older the trend is easy to see. We are losing much of our skilled workforce to high technology, which shifts as often and regular as the tide. Does this mean that instantaneously all perspective students will graduate into a white collar work force, not at all. What bothers us the most, from looking at the thirty thousand foot view, is the overall loss of skilled craftsmen on a large scale.
Chart is from The Atlantic article on job growth and decline - http://tinyurl.com/7f358qm
Chart is from The Atlantic article on job growth and decline -http://tinyurl.com/7f358qm
With all that in mind, take a read on the article and videos below about Ford Motor Company and the innovative TechShop in Detroit. Employees are allowed to access the facilities whenever they want and to work on their own projects. Perks are even given out to potential windfall projects that could be used on new vehicles. Needless to say, that is an amazing idea on how to help innovate for the future while keeping hands on skills at the ready, bravo to Ford!
"Before he invented the assembly line, Henry Ford built his first prototype on a workbench in a shed. More than a century later, his company has partnered with TechShop, Detroit, the 21st-century equivalent of that shed, with a bold program to ignite innovation in the company.
Ford employees who invent something that the company ends up patenting receive a free three-month membership to TechShop, where they can flex their creative muscles. Project sponsor Bill Coughlin, CEO of Ford Global Technologies, has high hopes for the partnership. He expects it to supply Ford with innovative new features for its fleet of automobiles and also to act as a catalyst for Detroit’s economic recovery, generating new businesses and jobs.
It’s easy to see why the program is appealing to Ford’s designers and engineers. The Detroit TechShop is an amazing 17,000 square feet, stocked with $750,000 worth of laser cutters, 3-D printers, CNC machine tools, and staffed with “Dream Consultants” whose job it is to help you fabricate pretty much anything.
Ford employees are free to use the space day or night, for projects related to their work or personal projects. So far, employees have used the tools to prototype new features for car doors and for more fanciful pursuits like one employee’s “Whirlygig,” a plastic sculpture made with a laser cutter that spins in the wind and reflects light in interesting ways.
Since launching the program, patent disclosures are up an impressive 30 percent, but Coughlin thinks there are more long-term organizational benefits. Disruptive ideas, for example, are more likely to be taken seriously.
“An idea on paper is easy to kill, but when you create a prototype of it and a supervisor can see it and experience it, it’s harder to say no,” Coughlin says. “Once someone starts thinking creatively it’s hard to turn that off. People stop seeing problems and start seeing opportunities.”
The partnership also promises to forge deeper relationships between Ford, its suppliers, and the maker community. How? The automaker recently asked a manufacturer of an environmentally friendly material to bring samples to TechShop to see what members could make with it.
Coughlin is a lawyer by training, But decided to temporarily trade in legal briefs for a bandsaw. He posed a simple question to himself: “Could I do better than Ikea?” After taking a couple of classes, he successfully designed a flat-pack end table and worked on another prototype using a ShopBot (an industrial-strength CNC cutter). He won’t comment on whether it is IKEA-worthy, but does say that it is at least “dimensionally stable.”
Coughlin’s group at Ford is responsible for filing patents for the company and monetizing the thousands of patents it already has. Open source hardware advocates aren’t big fans of patents, viewing them as impediments to innovation. But Coughlin points out that many Ford patents are for the greater good — and shared with the industry at large — like the pernicious beep your car produces when you don’t buckle your seat belt. The profits his group generates helps fund new programs like the partnership with TechShop.
Still, the program raises some thorny legal issues for inventors. If an engineer designs something in his free time and funds it on Kickstarter, say, would Ford own the patent?
Coughlin says there is a process for employees to clear after-hours projects, and in all but one case, they’ve been free to pursue their ideas without fear that Ford might claim ownership. And employees who create patentable projects related to the auto industry receive a portion of revenues generated from the patent.
Will the TechShop partnership help to beef up the dashboard tech too? At Wired’s Disruptive by Design Conference, Ford CEO Alan Mullaly pointed out that Ford would be foolish to install cutting-edge electronics in the dash, as they’d be inmediately obsolete — consumer electronics advance much more quickly than the automotive industry. Instead, drivers can just pop in the latest iPhone and leverage all of Apple’s innovations.
At every level, Ford seems to realize that the days where customers could “choose any color as long as it’s black” are long over. The future of innovation lies in the hands of customers and employees who identify automotive design problems. Giving those employees passes to a hackerspace is a giant step toward finding solutions."
Kevin Twomey is creating quite a name for himself with his photography of vintage adding machines. What his photographs help to portray is the mechanical complexity to which numbers could be added up to infinity, through a physical and extravagantly designed solution. This setup was commonplace for many decades and now with the advent of hi tech computing these mechanical devices have gone the way of the dinosaur due to their singular function, weight and inability to compete in today's market place of apps on mini computers.
They may seem like Rube Goldberg machines today, but mechanical adding
machines were considered the closest thing to computers not long ago:
heaps of gears, levers, and springs engineered to do the work of a $3
calculator. The San Francisco–based photographer Kevin Twomey has produced a wonderful series of these mechanical relics, selected from a collector’s private stash.
“The community of people who collect this cumbersome,
not-so-valuable, obsolete machinery is pretty small,” Twomey tells
Co.Design. Nonetheless, his research quickly led him to Mark Glusker, a
collector and mechanical engineer living just a few miles from the
photographer’s studio who agreed to bring over a few prized pieces. “As
we laid them out on tables, Mark pulled off the covers on some of the
machines to show me the guts,” Twomey recalls. “Instantly I knew what
this project was about: the intricate and complex inner workings of
these machines.”
Kevin Twomey's photos show the depth and soul of a vintage adding machine
He used hot lights to illuminate the details: “Arri hot lights have a
crispness about them, so when objects like these machines are bathed in
that kind of light, they just sing,” he says. And his affection for
vintage technology extends to his own choice of equipment: a Hasselblad.
“I am still in love with the older Carl Zeiss lenses.”
So ya dig messing around with vintage motors and rides, well how much do ya know about a carburetor's functions? Don't lie, ya probably know about as much as the rest of us and are online looking at ways to fix the gas problems you are encountering with vacuum leaks, cheap gas or gunked up jets, haha! No matter how much we know, we can still never know enough when it comes to the basic principles of an air and gas mix to make your motor fire efficiently.
We have cut our teeth on many styles of carburetors from tinkering with lawn motors, tractors, motorcycles and old v8's. After coming across this article over on Popular Hot Rodding we knew it might help to dispel many myths about tuning carburetors. This article in particular focuses on carbs for hot rods but take the general principles and apply them to bikes as well.
Some stories are so obvious and necessary that it's difficult to identify the need. Surely everybody knows what a Q-jet looks like and how to tell it apart from an old Carter or a Holley 4150. "Not so fast, Mr. Smarty Pants Editor," you might say. "Don't take so much for granted." Hard to believe, but a carburetor hasn't been placed atop a new production car or truck since 1988. That's 20 years ago, folks. To put it into perspective, a kid who graduated high school in 1988, then got a job as a line mechanic at a new car dealer after Vo-Tech training, could conceivably be a 20-year veteran without ever having been paid to turn the idle screws on a Holley. That puts things in a whole new perspective. Then there's the guy who only knows Holley carb architecture (which includes Barry Grant, QFT, and many other smaller manufacturers), never thinking to try a new Edelbrock or a Sean Murphy Q-jet.
To another point: We'll be generically referring to carbs here as "Holley," "Quadrajet," and "Carter." There are many manufacturers that use the Holley architecture, so using the term "Holley" is strictly a convenience to keep the reader from getting confused. The term "Carter" is essentially the same case, though current Carter carburetor architecture is strictly all Edelbrock these days. The Rochester Quadrajet is out of production but is currently available from several sources only as a rebuild. Our thanks to Sean Murphy for providing one of his seriously refurbished units.
The idea here isn't to compare the pros or cons of one carburetor architecture over another, but to do a straightforward walk-around of the three major types and to show you where to "turn the dials," so to speak. Maybe after reading this, you'll want to step out of your comfort zone and try something new.-Johnny Hunkins
The last thing the world needs is another carb versus EFI story, so we'll spare you the rehashed and inconclusive monotony. What the collective hot rodding community can use is back-to-basics carb tech. Despite its perceived simplicity, meeting the changing fueling demands of a motor- from idle to cruising to WOT-strictly through mechanical methods requires a complex device. The maze of fuel and air passages that constitute a carburetor is hardly intuitive in terms of functionality, and basic carb tuning requires understanding how it all comes together. Furthermore, Holley (aka modular), Carter (now Edelbrock), and Quadrajet carbs all take different approaches to performing the same task. To help those less familiar get up to speed, we'll cover the basics of how carbs work, reveal simple tuning tips, and divulge the differences between major carburetor platforms.
This
cutaway of a Barry Grant Demon carb clearly illustrates the atomization
process. Fuel from the float bowl passes through the main jet and
enters the emulsion tube. The fuel is emulsified by air entering the
emulsion tube through the air bleeds. View Related Article
How Carbs Work
The principle of carburetion is really quite simple. In liquid form, gasoline does not burn and therefore needs to be vaporized. Through an elaborate network of internal air and fuel passages that rely on rudimentary physics, carburetors introduce atomized fuel into the air stream above the intake manifold plenum, which then vaporizes into a gaseous state by the time it reaches the intake valves.
Fuel is pumped into the bowls through the needle-and-seat assembly, and then drawn into the intake through the pressure differential created by the venturi effect. The hourglass shape of a carburetor's venturi increases air speed in the section where it necks down, creating a low-pressure area. It is this reduction in air pressure that enables fuel to be pushed from the fuel bowls into the intake manifold. "Think of a carburetor as a fuel injection system that operates at 1 psi of pressure," explains Judson Massingill of the School of Automotive Machinists. "Everyone thinks manifold vacuum pulls fuel out of the carburetor, but since manifold vacuum drops to zero at WOT, it's the pressure differential that's doing all the work. Fuel bowls have air vents in them, which means that there's 14.7 psi (normal atmospheric pressure) of pressure pushing down on the fuel. The venturi effect reduces pressure to about 13.5 psi at the manifold, and that 1 psi of pressure differential is all it takes to push fuel through the carb." Moreover, boosters in the venturi, which act as a venturi within a venturi, further increases the pressure drop (carb signal) without significantly compromising airflow.
Even so, the fuel droplets would be too large for effective atomization without a means of introducing air into the mix through emulsification, and that's where the air bleeds come in. Emulsion tubes carry fuel from the fuel bowls to the venturis and preatomize the fuel by mixing it with air channeled in through the air bleeds. The effect is similar to drinking through a straw that has a hole in it. Ensuring thorough atomization, and therefore complete vaporization of fuel, yields more thorough combustion, increased power, and reduced emissions.
Circuits
Unlike many industrial motors, the load and rpm a car engine experiences is in a constant state of flux, whether it's idling, part-throttle cruising, or at WOT at the dragstrip. Meeting these fueling demands through mechanical means require several networks, or circuits, of air and fuel passages. These consist of the idle circuit, primary and secondary circuits, fuel enrichment circuit, and the accelerator pump circuit. As its name suggests, the purpose of the idle circuit is to provide fuel at idle. Likewise, the primary circuit delivers fuel in proportion to the throttle angle of the primaries, while the secondary circuit initiates additional fuel flow once the secondaries kick in. "While it's true that changing the tune on one circuit can affect another, each circuit can be individually tuned to effectively meet the needs of the engine's operating range that it affects," says Victor Moore of Barry Grant. "However, this means that there are often several ways to address a single issue."
Carburetion
would not be possible if not for the venturi effect. As air travels
through a carburetor, it speeds up in the section where the venturi
necks down in diameter. This creates a low-pressure area, which allows
fuel to be drawn into the carburetor.
The fuel enrichment circuit, or power valve, adds fuel only at WOT, and is typically found on the primary side of the carb. This allows running smaller jets for crisp cruising and throttle response and adds extra fuel only when needed. At idle and part-throttle, manifold vacuum keeps the valve shut. However, when manifold vacuum drops at WOT, the power valve opens up and adds the equivalent of 7 to 10 jet sizes of fuel. "With a typical Holley, that means you can have 72 jets up front and 80 jets in the rear so it cruises real nice going down the road. But when you go WOT it's like having 80 jets in the front and back," Judson explains. "Everyone wants to block the power valve, but if you block it and then go faster, that just means you were 7 to 10 jet sizes too rich in the first place."
The accelerator pump circuit is akin to a mechanical fuel injection system and is the only circuit on a carb that is not affected by airflow. It is designed to help speed up fuel flow when the intake charge stalls under heavy loads by providing a small squirt of fuel. "People think that when you floor the throttle and the motor bogs, it's because the carb dumped too much fuel into the motor, but the exact opposite is true," says Judson. "What's actually happening is the volume of air entering the carb is so great that the carb signal drops to where the air stalls and no fuel can be delivered. The accelerator pump combats this lean condition by squirting fuel until air speed and carb signal picks up again, easing the transition between light and heavy throttle."
Carb Sizing
A quick Google search will find several formulas that recommend a specific carb size based on factors such as engine displacement and rpm range. While they're better than nothing, they offer ballpark estimates at best. "If you have cylinder heads that move a lot of air and a cam that takes advantage of that airflow, you need a much larger carburetor than those charts recommend,"explains Judson. "However, I fyou have factory heads that aren't very good, you're better off with a carb that's smaller than the charts recommend."
Regardless
of the carb platform, all that have fuel bowls have vent tubes. The
pressure differential between the air in the venturi and the ambient air
pressure pushing down on the fuel through the vent tubes is what sets
fuel flow in motion from the bowls to the boosters. Covering the vent
tubes while a motor is running will kill it immediately.
Perhaps the best way to dial in carburetor sizing is through trial and error with a vacuum gauge. While cylinder heads are flowed at 28 inches of water, carburetors are flowed at 1.5 inches of Hg, which equates to roughly 20 inches of water. Consequently, if a motor never pulls 1.5 inches of vacuum, then the carburetor never flows at its peak potential. According to Judson, on a typical street/ strip motor, it's ideal to shoot for 1.5 inches of vacuum at Wot.
Start with a carb on the small end of the spectrum-such as a 650-cfm unit-hook up a vacuum gauge to the intake manifold, and run the car up to peak rpm. "If it pulls, say, 2.5 inches, you know that the carb is too restrictive,and you need to step up in size," Judson explains. "Let's say you ran the same test with an 800-cfm carb and only pulled 1 inch of vacuum at WOT. Then you might have picked up some horsepower up top at the expense of low- and midrange power, in which case you should size back down to somewhere in between." Furthermore, a carb that is too large won't show any kind of reading on the gauge, which means it isn't presenting any restriction in flow whatsoever -most likely resulting in poor low-rpm metering. It's better to err on the small side than the large side when it comes to carb sizing, but shooting for 1.5 inches of vacuum at WOT will typically yield the best compromise between peak horsepower and driveability.
Jet Sizing
Understanding how jets regulate the air/fuel ratio is rather simple. Larger jets (with bigger numbers) richen the mixture, while smaller jets lean it out. However, jet sizes don't necessarily correlate to a specific diameter. For instance, a 40 Holley jet has a .040-inch diameter, but a 70 Holley jet has a 0.073-inch diameter. That's because all jets are numbered based on what they flow, not their drill size diameter., Just remember: The bigger the jet, the greater the flow.
The
needle-and-seat assembly and float control the fuel level in the bowl
much like a toilet. Fuel enters the bowl through the seat, which
gradually raises the pivoted float arm. As fuel level rises, the float
arm pushes up on the needle, which slides into the seat and seals off
the fuel passage when the bowl reaches maximum capacity.
Judson's Six Tips For Carb Nirvana
1 "Everyone wants to put bigger jets in a carb because they have a hot rod and think more fuel equates to more power. The exact opposite is true. Lean is mean. The average carb is engineered on the rich side to save you, so fine tuning usually involves removing fuel from a motor, not adding it."
2 "Bigger isn't better. Don't just go out and install a bigger accelerator pump, a bigger shooter, and a bigger needleand- seat assembly. Carb manufacturers already know how much fuel a carb flows, and the factory setup is fine for 99 percent of motors out there."
3 "People think carb gurus can get more power out of a motor because they make the carb flow more air, but that's not true. Where they get the power is in flattening the fuel curve from minimum to maximum rpm."
4 "Never start out by decreasing the jet size, or you'll risk burning a motor up. First, up-jet and make sure the motor loses power just to be safe, then startreducing jet sizes. As a rule of thumb, go up one jet size, and if you lose power, down-jet by two jet sizes."
5 "If you're running at the dragstrip, gauge your losses or gains based on trap speed, not e.t."
6 "Carbs work great as long as the fuel bowls are full. If your fuel system can't keep up, nothing you do to the carburetor means a thing, so it's paramount to have a good fuel system."
Vacuum vs. Mechanical
A carburetor's secondary throttle blades open up to provide additional airflow under heavy acceleration. This can be accomplished mechanically or via vacuum assist, and each has its pros and cons. For heavy vehicles with tall gears, it's generally accepted that a vacuumsecondary carburetor provides superior streetability and gas mileage. This is because the secondaries open up gradually as engine vacuum in the primary venturis increases with rpm. Mechanical secondaries, on the other hand, are directly linked to the gas pedal. Typically, mechanical secondaries will begin to open at 40 to 45 percent throttle. They have a reputation for "hitting harder" than a vacuum-secondary carb at the expense of driveability and are better suited for more serious engine combinations. Additionally, some (but not all) mechanical-secondary carbs feature a second accelerator pump, so some (but not all) mechanical-secondary carbs are double-pumpers. Despite their reputations, vacuum-secondary carbs can support massive horsepower, and many enthusiasts flog mechanicalsecondary carbs with great success on the street. The introduction of Barry Grant's vacuum secondary King Demon (4500 series) recently is a good example of this.
Easily
accessible dual float bowls, power valves, and jets make the modular
Holley-style carburetor one of the easiest to tune. This unit is a Barry
Grant Mighty Demon. The dual accelerator pumps, in conjunction with
mechanical secondaries, allow transition from part- to full-throttle
without bogging. Few carbs have the street cred of the Holley-style
double-pumper.
Tuning
A detailed guide to carb tuning is beyond the scope of this story. Dozens of books have been written on the topic, but the question is, is it even worth bothering with? "Carb manufacturers have done an incredible job of engineering their products right out of the box," Judson explains. "All these bracket racers and street squirrels want to tinker with them, but they mess them up more than they ever improve them. As long as you size carbs properly, they're so good out of the box, it's unreal. Even if you're a great carb tuner, you might only get another 1 percent out of a motor."
A
trick feature of the Mighty Demon is the annular discharge booster. The
setup yields a finer mist of fuel for improved atomization and throttle
response. Boosters are easily replaced if altering the signal strength
is required. The greater the booster's restriction to flow, the stronger
the carb signal-and vice-versa.
Nonetheless, there is a time and place for altering the factory's calibrations. "Out-of-the-box carbs are fine for street/strip motors, but if you're building a race motor, you need a race carb," says Dave Braswell of Braswell Carburetion. "Race cars operate in environments that street cars never see. For instance, since drag cars launch so hard, we've developed carbs that can deliver fuel at 3 g's without uncovering the main jets."
Granted, that's an extreme scenario, but where most gains can be picked up is in the fuel curve. Production carburetors are intentionally tuned to run slightly rich at high rpm for safety. Flattening out the curve is best left to a pro, but doing so can yield dividends. "Every engine wants a different fuel curve, and the fuel port passages in a carb are like the cross-sectional area of the ports in a cylinder head," explains Patrick James of ProSystems Carburetors. "We modify the fuel passages to make the emulsion process more active and custom-tailor the diameter of the fuel ports and fuel curve to each application. There's more to it than simply adding more fuel; it must be introduced in a burnable fashion."
Holley Carbs
Numbers aren't always an indicator of quality, but the Holley modular fourbarrel is the most popular performance carburetor in the world. George and Earl Holley started building carburetors in 1904, and the company has since produced over 100 million units. After introducing a pair of 370-cfm fourbarrels in the early-'50s-Models 2140 and 4000-Holley launched its legendary 4150 model in 1957. Amazingly, that same basic design architecture has been chugging away for over 50 years, with continual refinements increasing airflow from 400 cfm in 1957 to more than 1,000 cfm today.
The
Holley-style modular design offers easy fuel level-adjustment, and it's
accomplished similarly to this Demon carb cutaway. The needle and seat
can be externally adjusted by simply turning this screw.
The 4150's big brother-the model 4500 Dominator-was developed by Holley for Ford in the late-'60s to assist the company in its quest for NASCAR and Trans Am racing glory. The original Dominator flowed 1,150 cfm and was used on Ford's 429- and 302ci race motors. Today, the Dominator is available in flow ratings ranging from 750 to 1,050 cfm and is the carburetor of choice for hoards of hardcore racers.
In response to the changing needs of the OEs due to smog concerns, Holley has introduced countless carburetor models over the years. These include emission-friendly models, and even carbs designed as high-performance Quadrajet replacements. Nevertheless, the 4150 and 4500 series carbs are unrivaled in their popularity and street cred. Over the years, various manufacturers (such as Barry Grant, Brasswell, and QFT) have introduced their own product lines based roughly on the Holley modular architecture.
Quadrajet Carbs
Vilified by the masses yet embraced by experienced carburetor tuners, the Rochester Quadrajet has gotten a bad wrap over the years. Dubbed the "Quadrajunk" by the uninitiated due to its complexity, the Q-jet is quite possibly the most versatile and advanced carb ever built. "Since it was designed as a GM production carb when emissions laws were getting stricter, it had to, be very accurate," says Sean Murphy of Sean Murphy Induction. "When tuned properly, a Q-jet is hard to beat. Fuel mileage, top-end power, and low-end torque-it can do it all."
Located
in the metering block, the power valve is easily accessible and
replaceable. Power valves are rated at the inches of manifold vacuum at
which they open. For instance, if an engine
pulls 7.5 inches at idle, the carb should be fitted with a numerically
lower (2.5-,3.5-, 4.5-, 5.0-, or 6.5) power valve to prevent running
overly rich.
As with EFI, it's the Q-jet's precision that can make it finicky at times. Although Holleys and Carters can be extremely forgiving of tuning errors, this isn't the case with the Q-jet. "Due to its precision and accuracy, Q-jets won't let you be nearly as sloppy with tuning compared to the other carburetor platforms out there. You can't take a Q-jet that was running well on one motor and stick it on another motor and expect it to run right. Even small changes in compression or cam can really upset the tuning."
Built by the Rochester Products division of GM, the Quadrajet first appeared in 1965. Designated the 4M, it featured small-bore primaries for improved throttle response and fuel economy and large-bore secondaries to meet fueling demands under heavy acceleration. During its reign of over 20 years, the venerable Quadrajet was used by every GM division. It survived well into the '80s, even implementing computercontrolled engine management over many of its functions, until finally being phased out in favor of EFI.
Large
throttle angles push the accelerator pump's lever against its diaphragm
to initiate fuel enrichment when throttle angle increases. The pump can
be tuned with interchangeable pump cams to alter its fuel curve.
As a production piece, the Q-jet was never designed to be a highperformance carb. However, all Q-jets flow a minimum of 750 cfm, and some flowed a very respectable 800 cfm. Furthermore, NHRA Stock & Super Stock racers have been pushing well over 600 hp with Q-jets for many years. The Q-jet was continually refined over the years, and the first major redesign came in 1975. Called the M4M, o rmodified 4M, it boasted a larger fuel bowl capacity, a revised adjustable part-throttle (APT) system, and larger primary bores. The Q-jet went relatively unchanged until the middle of the '80 model year, when it implemented electronic controls and was dubbed the E4M (Electronic 4M). Consequently, the '75-'80 castings are the most coveted by hot rodders.
Carter Carbs
Noted for its simplicity, reliability, and adaptability to a myriad of applications, the original Will Carter fourbarrel (WCFB) carburetor dates back to 1952 when it was first introduced on Buick straight-eight engines. It was a cutting-edge piece for its time, used as factory equipment on C1 Corvettes and Chrysler Hemis, but increasing power levels of the era demanded higher air- flow capacities. To meet these needs, the Carter AFB (Aluminum Four-Barrel) was introduced in 1957 and was used as an OE carb by Chrysler, Ford, and GM throughout the years. The AFB earned a reputation for potent off-the-line punch, and engines such as the Pontiac 421 Super Duty-which used a pair of AFBs-helped reinforce that image. Although Carter didn't rate the flow of its carbs, the AFB is believed to have flowed between 450 to 625 cfm.
Idle
screws located on the metering blocks can often cure a rough-idling
motor. Turning the screw clockwise leans the mixture, while turning it
counterclockwise richens the mixture. However, in certain emission
"reverseidle" carbs, the exact opposite is the case.
By 1966, the AFB was superseded by the AVS (Air Valve Secondary) carb and was used primarily by Chrysler. The AFB and AVS look almost identical from the outside, which is partly why the AVS never gained widespread acceptance by hot rodders. "The biggest difference between the AFB and the AVS is the AVS has a spring-loaded secondary air valve as opposed to the AFB's counterweighted air valve," explains Smitty Smith of Edelbrock. "The AVS' air valve is adjustable to better suit heavy vehicles, whereas the AFB's valve is not adjustable." Another key difference is the AVS' lack of secondary booster venturis, although Edelbrock has revised the original design by adding boosters to its Thunder Series AVS carburetors.
Long after the AFB had been phased out, Carter brought it back in the mid- '70s as the Model 9000, updated with an electric choke, emissions provisions, and OE throttle-linkage compatibility. Due to the rise of factory EFI in the mid-'80s, Carter lost significant market share and was sold several times before being acquired by Edelbrock. Today, the company offers AFB and AVS carbs, with flow ratings up to 800 cfm, with both square-flange and spread-bore bolt patterns.
Mechanical aptitude comes in many forms, for me personally its in fabrication and general building principles. Engines, gears, parts, etc. all look like puzzle pieces in my head and I can see how they fit together based on shape and perceived function. Sometimes it might be a bit of trial and error akin to tuning a carburetor, but figuring out the precision aspects is half the fun. For other folks such as Chief its all about electrical engineering and "potential" energy. His mind wraps around it like a tortilla engulfing some tasty carne asada, rice and beans. Or we have someone such as Josh over at Wrench Works that dials into in the workings of all individual parts and fully understands the machinery as a whole and can refine the mechanical processes throughout. Lesson here is to make good friends who know what you don't know, sound familiar?
So ya wanna know about differential gears though, you say? Well, if your not Bert Bakerand those gear ratios are giving you a hard time, sometimes its great to start from the beginning as we can't know everything, but can sure as hell learn more.
While our brains are crunching on gear ratios for our street fighter and new axle and transmission setup for the '51 Chevy shop truck we had to research a few places to dig into the basics and get our working plans in order.
Only thing missing from this video is if it was being narrated by Patches O'Houlihan.
