Tack25

Will you guys list some of the advantages and disadvantages of having a carb as opposed to a fuel injected 3rd gen? That would be really really helpful. Thanks

88IROC350TPI

Advantages = cheap, ease of tuning, ease of troubleshooting, less parts to go wrong, easy to tear down a carbed motor

Disadvantages = Not as precise as fuel injection, can't automatically compensate for different conditions

dankhound

Agee with all of the above except the fewer parts to fail. Theres gotta be a million parts in a carb. No not really but theres alot. Fuel injection is probably easier to work on until you become familiar with all of the parts and circuits of the carb.

Disadvantage:Fuel economy. Although a properly tuned carb can come close to injection as far as economy is concerned.

88IROC350TPI

a million parts? I count only 222 http://holley.com/HiOctn/TechServ/TechInfo/4150-60.html

over a 150 of which are non moving parts and gaskets that will likely never go wrong. All those parts (cept for the electric choke if you run one) are also mechanical as apposed to electrical - much less likely to fail and even if something does go wrong you spend $30-40 on a rebuild kit and your carb is as good as new. Can you do that with EFI?

ljnowell

I've never thought fuel injection was easier than a carb. I mean come on, a couple of screws, maybe a jet change. It beats the living hell out of usign laptops and cables and burning proms, and dealing with all of that headache. I'll take a carb anyday, unless of course it is my winter driver, then i dont want any part of that yucky old carb!

dankhound

Obviously a million was an exageration. 222 is still alot more parts that can fail than on a FI.
I agreed with 88Iroc350TPI that carbs were easier to tune. The only thing that makes the FI easier to work on(in stock form at least) is the fact that the computers "intelligence" can point you in a direction when things arent running right. Diagnosing a carb takes a bit more skill because most carbs are aftermarket and dont give the user the benifit of a starting point for diagnosis.

Apeiron

There isn't much difference in the difficulty or skill required to tune a carburetor or fuel injection system. Both systems use computers to meter fuel, air and spark in response to a variety of inputs. The difference is that a fuel injection system's computer is typically electronic and a carburetor's is typically mechanical.

Apeiron

And if you're going to be absurd and cite every component in the carburetor as a source of failure, pop open the ECM on a fuel injection system and count the electronic components.

88IROC350TPI

Thats INSANE to think like that. Like I said all of those parts are mechanical, mostly non-moving, or gaskets. The ONLY things you'll ever read about failing on a carb is: power valve, needle/seat assembly, floats, maybe a gasket drying up and failing, or the linkage rusting up or getting bent. If you have a carb problem I can guaruntee its one of those simple things to fix. Now you have a EFI it must have thousands of controls, a "million" sensors, all kinds of electrical wiring, so on. The oldschool saying goes "90% of all carb problems are fixed with points and plugs" Whys that? because carbs are as reliable as the sun rising.

What do you think is going to be more likely to fail? What do you think is going to be easier to diagnose and fix? The trusty 100+ year old mechanical and simple technology called THE CARBURETOR or the complicated electronically controlled fuel injection?

Its simple to think that EFI is easier to tune, diagnose, and less likely to fail than a carb. There is absolutely no logic behind it.

ljnowell

My car has absolutely no computer controlling anything. And I like it that way. I cant see how you can even compare tunign a carb to a FI engine. Apples and Oranges. The fuel injection isnt simple at all.

Apeiron

Like it or not, your carburetor is a mechanical computer.

ljnowell

Like it or not, it isnt. A computer is a device that computes logics by using a series of electrical pulses. I dont believe that my carb does that. Do you?

five7kid

iTrader: (14)

There are computer controlled carbs out there, guys. As in every US-delivered 3rd gen between 1982 and 1987 that had a carb.

But, since the originator has TBI, that's moot.

Carburetors are an open loop control system. Inputs are throttle position and vacuum. Output is pre-set based on those inputs.

Electronic fuel injection (as done by the factory) is open loop in cold-operation conditions, and closed loop after the engine starts to warm up.

In the controls world, closed-loop is considered superior.

However, it is also typically more expensive. The factory was driven to it by emissions and fuel economy requirements. The performance world was the beneficiary.

In a recent mag, there was an article about a guy with 2 Camaros - an old-school 1st gen with carb, and a 4th gen with EFI. Both ran 10's. He could drive the 4th gen anywhere, and he tuned it with data on a laptop. He said the 1st gen was a handful (I think he used "scary" somewhere in the dialogue), and he tuned it by old-school methods (reading plugs, 1/4 mile mph, and by "feel").

He had a bucketload of money in each of them.

If you get your kicks on the keyboard, go EFI. If you like getting your hands dirty and smelling like gasoline, go carb (although, when I think about it, I haven't touched the carb since April, and I've made about a hundred runs since late April).

ljnowell

There are definately CC carbs, I've had a few. But to call all carbs a "mechanical computer" doesnt make much sense. I couldnt see tuning 10 second car with a carb being scary in relation to a 10 sec car with FI though. He must have had one hell of a carb setup.

five7kid

iTrader: (14)

The scary part related to the way the cars drove under power, not the tuning.

sqzbox

A carburator's computer is in your head! A carb. is just a metering device. A computer can make changes in less than a se. Unfotunatly, the human brain can't. That's why they invented the computer controled EFI system. Even though it might not be tuned for max power all the time, it does deliver exact, precise, air fuel ratio's under different conditions in order to meet clean air standards. That's the ONLY reason they found their way into our cars! Now that they have cars with 300 plus Hp your paying $30,000 for a 5000 dollar car with a computer! And you can't even surf the web with it! I'll bet, I can put an aftermarket 4 barrel (600 cfm universal) and manifold with an HEI and a hot coil,
and run quicker times than my EFI BUT, my fuel milage is going to suck and the emisions will stink! I'll choose 26 MPG over 13-14 any day now though. Maybe someday when gas is under a buck a gal. I might consider it!

Apeiron

That's an electronic digital computer, which is only one type of computer. Mechanical analog computers, of which the carburetor is an example, were around long before the electronic computer.

Carburetors process inputs (vacuum, airflow, throttle position, throttle opening speed), and produce an output (a metered amount of fuel to produce the correct fuel-air mixture). They're programmed by changing mechanical parts to alter the behavior produced by various inputs.

A fuel injection system might use a few more inputs, and might be programmed electronically (although not necessarily, anyone remember mechanical fuel injection?), but both perform the same job in essentially the same way.

five7kid

iTrader: (14)

Mechanical fuel injection (certainly not the '57-'65 Rochester type) is not feed-back.

Apeiron

No, certainly not, and neither is a carburetor, as you pointed out earlier.

Tack25

Which of the two would it be easier to make power with? It seems to be easier to fine tune the carb but so far I see no reason to stick with the fuel injection.

ljnowell

You cant call a carb a computer any more than a fuel pressure regulator. A carb meters fuel. Thats it.

sqzbox

Yeah, what he said!

nsimmons

Do a little research, there was mechanical computers and or adding machines in the 1800's, your carb is a variation of the idea, as in it takes inputs, processes and gives an output. Try studying a litltle computing theory.

sqzbox

Tell that to my carb. Maybe it'll learn something so it will make my car go faster!

nsimmons

yeah personally having majored in computing theory i much prefer punching keys over turning screws. Now i have to learn this carb business. If only i could plug a keyboard into my carb.

ljnowell

Hmmm. that is too ****ing funny. Lets see, I have an associates degree from a technical college in Computer Networking, A bachelors degree in computer science (networking and engineering) and currently hold the following certifications: CCNA ( Cisco Certified Network Associate), Net+, A+. MCSE, MCSE 2003, CNA (Certified Novel Administrator), Linux+, Microsoft Security Management. I am a certifeld dell technician and I am also Licensed to do warrranty repairs for the HP/Compaq conglomerate. My current job is building and supporting servers and routers that probably cost more than 99% of the cars here. Do you think I have enough knowledge of computers?????? A carb is in no way a computer. No matter what, give it up. It is a device that is used to deliver the proper amount of fuel to an engine. If we are going by your standards then i guess a transmission is a computer too. Because it takes an input and multiplies it by a constant and then delivers an output? Or a rearend perhaps?? I know a brake master cylinder takes an input from your pedal and bootster and applies it to the fluid to make an output that allows your car to stop. This is a stupid *** argument, and no matter what you excuses a carb is not a computer. Give it the F*uck up.

sqzbox

You can! With the proper hoses, you won't need to pump the accordian!:rockon:

ljnowell

By the way, the day that my carb starts functioning via boolean expressions is the day that you can call it a computer.

sqzbox

Man, this thread is getting crazier than I am! What was the topic again?

Apeiron

There you go thinking digital again.

Apeiron

Certainly the valvebody can be considered a hydraulically operated mechanical computer.

sqzbox

ljnowell, you don't suppose their still mad about the Stanley cup thing do ya? C-mon guy's, you'll get another chance next year!

nsimmons

backoff he's msce certified, he must know his sh*t..

im suprised someone who claims to be so learned cant differentiate between digital and analog.

Tranny analogy, excellent i might add.

ljnowell

sorry guys, we can play these games all day, but none of these items (trans, carb, or the like) can be considered a computer. It cant be. YOu can try all day. You can use them as an analogy to explain a computer, but they are not computers. And I am not knowledgable because I am MCSE certified. I am knowledgeable because I have 6 years of college, two degrees, countless certifications, and the real world experience and JOB to make it count.

I didnt insult you and I would appreciate it if you didnt insult me. Cant differentiate between analog and digital. Yeah thats it. You hit the nail right on the head. Because I am so stupid I guess I will just have to settle for being in my mid twenties and making 68K a year because I am stupid. Thanks for clearing that up for me.

This has turned into quite possible the most retarded thread that I have ever seen on these boards.

Also for your information analog signaling is also an electrical pulse. It uses a wave of highs and lows. Digital uses set logics (1,0). What you are referring to is mechanical inputs, not analog. Go back to McDonalds parking lot and talk to your friends some more about computers.

edit:spelling

Apeiron

Having lectured on software engineering principles at a technical college probably very similar to the one you attended and having possibly written some of the software which resides in the routers you use in your work, let me say that you are justified in your pride in your achievements. It is important to remember however that especially this early in your career you have not seen, done and learned everything. Nor have I, for that matter. If your background had included more experience in control systems or perhaps the history of computation, you would be much more comfortable with the concept of single-purpose computers which do not employ the von Neumann architecture.

Regardless, before we were sidetracked, the point I was attempting to make is that a carburetor is, if you refuse to see it as a computer, a device which is programmed to execute a deterministic function. For a given set of conditions, the carburetor should always produce the same results. If the carburetor does not perform as desired, the function may be modified by changing the programming of the device, which is accomplished by changing mechanical parts.

An EFI system behaves in essentially the same way, but the function is modified by changing the programming or lookup tables of the ECM. EFI and feedback carb systems have the additional advantage of being able to monitor their output at part-throttle with the O2 sensor, and so are somewhat self-tuning. At WOT, where narrowband O2 sensors are useless, there is little distinction.

Apeiron

Oh, and sqzbox, I used to live in St. Petersburg, but I live in Edmonton now. My two favorite teams are the Edmonton Oilers and whoever is playing the Calgary Flames.

ljnowell

I agree entirely with what you are saying there. That is 100% true. A carb is a very well tuned device, or more or less a machine unto itself. It is every bit as advanced as a computer, and comparing it to a computer in the form of an analogy is a good comparison.

Ironically I will spent hours of every day working on computers that are more expensive than five of my cars, and then come home to my car with a carb because I dont like fiddling with auto computers. I know its sad.

ronterry

I agree with both of you, but I'm a student in Mechanical Engineering, and these carbs belong to me

Ron

sqzbox

I say! Don't they have mech. computers in China? I'm surprised you guy's didn't bring that one up! But, the little hand held beaded thingy still can't meter fuel and air for a constant ratio from 0 to 10,000 RPM. It might be able to compute the ratio, but once the equation is figured out it's cut and dried then the ratio is pre set and only a metering device will do the job! I might only have a high school ed. but I also have yrs. of racing exp. an 33 yrs. of hands on mech exp. I've gone from the basic engine, carb.,
gen. motor to what we have today! You give me the same budget it takes to build a computer controled engine and I can build one that will beat it draging a computer behide mine!
If it wasn't for the EPA, we wouldn't have computers in cars today. And remember, the computer had to be adapted to the automobile not visa versa. They were running just fine before the computer was even invented. Defense Rests

ljnowell

a mechanical computer is a calculator.

sqzbox

So much for the HS Education. Huh?

sqzbox

Now I'm worried! In the Army, I made several "jumps" from and airplane with a parachute! PLEASE tell me it's concidered a metering device and not a computer or calculator. Minus the fuel, it meters the air to control the rate of decent by a certain amount of weight. How much different is that than a carburator? Once the size of the parachute is determened it has to function the same with different weight whereas the CFM of the carburator matched to the engine has to perform with different auto gross weights.
I hate to think I rode a computer or calculator through the sky!!!

toecutterv8

fROM WHERE IM STANDING IM LOOKING at a load of turkeys who are arguing on a forum about everything and anything except THIRD GEN CAMAROS........come on guys,no way is a carb a computer,neither is a gearbox,or a brake system.PERIOD.Perhaps you should all go out and buy a book on mechanical basics so you can understand your cars a little better.Hell one day you may even make them faster!!!!Now for some information that may be of some use to you,anyone with fuel injection in perfect working order should measure the resistance of all the sensors and take note of the readings,this includes the injectors.Then when the day comes that it runs sick,you can measure the resistance of your sensors and sometimes the faulty item will be a long way of from the original reading.Both injection and carbs have their place in the world of modification,Im affraid though that carbs win everytime for reliability.

nsimmons

typical. the unenlightened response of the ignorant

name calling...

Does anyone here, besides Apeiron, actually know who John von Neumann was, or Mauchly or Eckert for that matter?

And if you cant explain to me the basis of the von Neumann architecture versus Harvard, im done reading this thread.

I'll let the monkeys continue to argue over the purpose of the monolith.

erictheviking

I would get your head out of your (illiterate) *** and stop bashing a person who's forgotten more about carbs than you'll ever know.I think in your case a little bit of knowledge is dangerous.Get your jigsaw back together and go and get yourself a girl.A carb is carb.

toecutterv8

[QUOTE]Originally posted by nsimmons
[B]typical. the unenlightened response of the ignorant

name calling...

Does anyone here, besides Apeiron, actually know who John von Neumann was, or Mauchly or Eckert for that matter?

And if you cant explain to me the basis of the von Neumann architecture versus Harvard, im done reading this thread.

I'll let the monkeys continue to argue over the purpose of the monolith.

Firstly i am not ignorant,i was purely making a point,This is crazy,how the hell can you call a gearbox,or a brakes system a computer.This is going way to far and as i said has nothing to do with camaros.Then you mention name calling,and at the end of your thread call everyone Monkeys!!!!! Perhaps you should take your 500 pieces,your college degree,and a laptop,throw them all into a Trash compactor.And program it to spit out a finished camaro.This way one day you may be able to drive your car.

88IROC350TPI

You guys are so silly.... Lets have dictionary.com solve the debate on the defination of a computer

A device that computes, especially a programmable electronic machine that performs high-speed mathematical or logical operations or that assembles, stores, correlates, or otherwise processes information.

n 1: a machine for performing calculations automatically


Sure, a carb performs calculations automatically, right? I still wouldnt consider it a "computer" though. Maybe a computing device?

Computing: To determine an amount or number.

toecutterv8

Thank you for shedding some light on this matter,a carburetor as you say(more or less),is not capable of making any calculations.A carb introduces a measured amount of fuel into a passing airstream flowing over the venturies,the flow of this fuel is governed by jets,which the OWNER can change to achieve the ideal air mixture.The fuel is drawn in by a"venturi effect" Higher airspeed,more fuel.The carb cannot calculate anything whatsoever,YOU change a power valve from a 15Hg to a 12Hg to alter the main jet enrichment curve.

To put it into terms for some of the other people above to understand,a carburetor blends fuel with air,in carefully measured amounts.In other words Its not a computer,but a type of FOOD MIXER.

sqzbox

Dude, that's a food PROCESSER in this century!

nsimmons

obviously my monolith joke went over all your heads

still nothing new has been added to the conversation, except "i know more about carbs than you." A statement both irrelevant, and unprovable. Well my dad can beat up your dad.

Grow up and learn how to debate. Try introducing statements that arent opinion to counter my position. More correctly you believe you know more about carbs than me. To say you know it would imply you and everyone else in existence would have contingent knowledge of the truth value of said fact. Obviously that is not the case.

boring..later