Thread: fuel injection

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One item I have not seen posted is on the different types of fuel injection units:
1.types available
2. adv/disadv of each type including costs
3. aftermarket vs. factory
4.factory or aftermarket wiring harness
Don

I'm starting to learn a little more abou the old style injection but I wonder. Is the typical Hilborn setup Alpha "N"?

Abe

Edit:
I decided to give answering some of the questions a shot. If I screw up please someone help me.

1. Typical are TBI, port and direct.

TBI (throttle Body Injection) is better than a carb and is comparatively cheap but is somewhat prone to fuel puddling, is not as fuel efficient as other types, and because of the typical location of the injectors somewhat restricted in airflow capacity.

Port is the best setup currently available but is more costly than TBI. Benefits are as follows. Low incedence of fuel puddling because of the injectors close proximity to the intake valves, ability to distribute fuel to each cylinder as needed and only as needed, possibility of very low profile induction system, and great tuneability in length, shape and diameter of runners.

Direct is still being fiddled with in spark ignited applications but when it does come around we will likely see fantastic improvements in emmisions, fuel mileage and performance.

Originally posted by Don Meyer
One item I have not seen posted is on the different types of fuel injection units:
1.types available
2. adv/disadv of each type including costs
3. aftermarket vs. factory
4.factory or aftermarket wiring harness
Don

Well Don,

This isn’t really a reply to your questions... but if you’ll indulge me, I just want to say a few things about the “basic” differences between my geezer carburetor setup and the computer driven electronic fuel injection systems.

Some folks around here know that I’ve been lusting for one of those Hilborn EFI’s for some time, so I’ve been trying to figure out all of the ancillary work involved in getting an EFI system to work properly. And from what I’ve learned so far, it’s a whole lot more difficult to convert a carburetor system to EFI than to build your project from the beginning with an EFI system in mind.

What I like about EFI (the Hilborn setup is icing on the cake) is that you can accurately fine-tune the system to provide the optimum air-fuel mixture for power (or efficiency) across the entire power curve of an engine. The down side appears to be “that it ain’t simple” for the average person to tune (or program) the system.

But before you even think about the tuning (or computer programming), you’ve got to have the right electrical and fuel plumbing system. There is a computer module and an array of sensors: O2 sensor to read the exhaust and determine if the air-fuel mix is too rich or lean, a manifold pressure sensor, an air inlet temperature sensor, and an engine coolant temperature sensor. And since the EFI system also controls the ignition timing, your ignition system is going to have to be compatible with computer controlled EFI too (no vacuum or mechanical advance).

What else is unique for the EFI system? You’ve got to have high-pressure type supply and return fuel lines (50 psi vs. 5 psi for carburetors), a special fuel tank with a sump (or modify your existing tank), a surge tank to help prevent air from being sucked into the fuel line, a fuel pressure regulator, special fuel pump, and special fuel filter. And also, your electrical system and wiring need to be in very good shape... static or noise in your electrical system will mess with the computer module!

I’m awfully intrigued by the EFI systems, but my ole geezer head has got some more learning to do. Maybe one of the young fellows can help to convince me that it's more simple than it looks

Dan J

Dan it really depends on how you look at it. I've rebuilt a couple of carbs (both Rochester) and I think that in comparison EFI is simpler.

Yes you have the sensors that come with EFI but with carbs you have needle/seat assemblies, metering rods, jets, accelerator pumps, slosh tubes, floats and such. That's allot of moving, bouncing, floating, sloshing componenets.

In comparison EFI has the injectors, throttle position sensor and the throttle plate as moving components. See the list is much shorter .

I know the list of sensors seems daunting but when you get a basic idea of how they work it's really not bad. And converting to EFI is not as hard as it may seem at first.

I'm pretty used to the GM MPFI MAP sensor based systems so if I can help in any way be sure to let me know.

Abe

Originally posted by The F.N.G.
I'm pretty used to the GM MPFI MAP sensor based systems so if I can help in any way be sure to let me know.

Thanks Abe. If I try an EFI system, I’ll certainly need some assistance. It sounds like you’ve been working with the electronic systems for a while. I know that the EFI’s have fewer mechanical parts than a carburetor, but it’s NOT the mechanical parts that are hard for me to understand

Tell me, how do you “tune” with a computer? Do you plug a wiring harness into the EFI’s computer module and then into a USB port on your PC computer? Do you buy software that is specific for a particular manufacturer’s engine, like a small block Chevy? And how do you program the different setups between a radical 383 and a stock 327? Are you optimizing the fuel mixture based upon the exhaust sensor’s readings? I’m assuming you’d need to put the car on a dyno to tune for power.

If you’ve done all of this, give me a brief lesson in what the process is (real world).

And what about all of the wires for the sensors (like Streets complained about)? Are they two wire (pair) connections, or does the setup require a large wiring harness?

If I go with an EFI setup, it would probably be something like this Hilborn setup... and even if I figure the operational stuff out, I’ll still have to convince my wallet that the expense is worth it

Dan J

Dan, here's a link to a site that does a pretty good job of describing the process. http://harrymoto.com/MX/maps.html

While this particular one is aimed at motorcycle guys, the concepts are the same. Some interesting info on the spreadsheet attachment.

Here's another link for the Holley Commander 950 controller. http://www.holley.com/HiOctn/ProdLin...A/534-144.html

The wiring harness size will depend on how many of the sensors you choose to use. They look pretty ugly when lying in a pile, but with some effort a lot of it can be routed in such a way as to not be too apparent. Remember how clean Trepanier made that engine compartment on the Ebay mustang look?

Most of the aftermarket suppliers of ECM's will include the software and instructions so that you can "play" with the mapping on your laptop. Or if you recall, the Mooneyes set up came with a "simple", dedicated, controller box with an LED readout panel.

Don, I'm not sure where you wanted to go with your original question. Were you fishing for info, say like the differences between mechanical systems (like the old Chev and Pontiac Rochester units) vs electronic? Or how much effort goes into assembling a complete system?

If you are willing to learn and be kicked around a little the new aftermarket FI units are wonderful when working. I have run the mechanical units most of my adult life but was absolutly no help when converting from a carb to a Holley 4DI. The mech. units are very basic. The pump puts out a supply, what you allow to return to tank removes from what goes in the engine....... If to fat or rich put a bigger pill or larger jet in pill box that returns to tank and viseversa.
The holley 4DI was way off and the techs at holley are worthless! Then 2 months latter they discontinued mine for release of Comander 950 and now had an excuse to tell me they would not help me. THANKS to Orin at A-Chart who sold software to monitor functions and was always willing to help I got it all working and was able to learn enough to make proper changes. I love the unit but still find Holley unwilling to support anything.
The electronic injection can and does do so much more than a carb or mech. injection ever could. Carbs are like an old faithful dog, won't let ya down but is limited, mech. injection is a new pup that is full of piss n viniger but has much to learn. Electronic injection is like a new bride, lots of fun - need to get used to each other and does not need an excuse for anything stupid it wants to do and no way to predict. good luck!!
Buy the elect. complete system and get good software like achartpro to allow you to customize so it works for you.

Thanks Bob! I'll add those links to my "homework" list, and I'll keep working my way down the path of EFI education. And I'm sure that all of the wiring can be installed neatly if some thought is put into the planning. You're right, the Ebay Mustang's engine compartment was very clean, so it can be done.

Originally posted by vettestr
If you are willing to learn and be kicked around a little....

Thanks for the encouragement Jeff, I'm just trying to avoid as much of the "being kicked around" part of this process as I can!

Dan J

Hi Bob P , I was just trying to start a new subject that might be educational to members.
Don

Originally posted by Dan J
Tell me, how do you “tune” with a computer? Do you plug a wiring harness into the EFI’s computer module and then into a USB port on your PC computer? Do you buy software that is specific for a particular manufacturer’s engine, like a small block Chevy? And how do you program the different setups between a radical 383 and a stock 327? Are you optimizing the fuel mixture based upon the exhaust sensor’s readings? I’m assuming you’d need to put the car on a dyno to tune for power.

If you’ve done all of this, give me a brief lesson in what the process is (real world).

And what about all of the wires for the sensors (like Streets complained about)? Are they two wire (pair) connections, or does the setup require a large wiring harness?

If I go with an EFI setup, it would probably be something like this Hilborn setup... and even if I figure the operational stuff out, I’ll still have to convince my wallet that the expense is worth it

Dan J [/B]

Dan you're not going to like this but that Hilborn has a VERY crude control system using very few inputs (2) and cannot be as efficient as it should be. I looked over the control systems specs and even though they are touting it as "simple as tuning a carb" it could turn out to be a friggin' nightmare if you were to change your setup.

Now to answer the basic questions.

How do you tune with a computer?

Each EFI system has it's own interface but generally you run a cable from a port in the car to a laptop PC. The software is not geared toward any specific size of engine but is instead flexible. You can set air and fuel flow rates in proportion to one another and some systems even alter the timing to go alongside the fuel air setup. Specific tuning generally starts with you setting the air/ fuel ratio far richer than it should be and tuning the fuel down until you get a good air/fuel ratio (typaically around 12:1-14:1). This is best done on a dyno using what is calleed a wideband O2 sensor but can be accomplished by good old fashioned plug reading.

Wires:

Most GM style sensors/senders are 2 wire for coolant temp, air inlet temp and in some cases crank position. Throttle position can be 3 or 4 wire (I think). Knock sensor is one wire. Nothing too fancy.


I hope I at least touched on the answers you were looking for. If not ask again and I'll try to zero in.

Abe

One more efi that was not talked about is the Edelbrook. I've heard good things about it.
Don

Originally posted by The F.N.G.
Dan you're not going to like this but that Hilborn has a VERY crude control system using very few inputs (2) and cannot be as efficient as it should be.

Thanks for the information Abe, it's been helpful. I looked at the wiring schematic and noticed that there were no 02, air inlet temp, or manifold pressure sensors required for the Rally System. Question for you, it's the computer module that needs all of the sensors (correct?), so your not talking about the performance of the Hilborn injectors are you? Correct me If I'm wrong, but don't the injectors only need to be given commands for when to "inject" fuel and how much fuel (air:fuel) to supply? If I'm correct, then can't you use different computer modules with compatible injectors?

I'm considering the computer and injector systems to be independent components.... I guess I'm trying to ask you if it's possible to change the computer component depending upon the level of "tuning" you want to perform. If I want "basic" tuning now, can't I trade up to a more sophisticated computer system later?

Dan J

There are a few different controllers on the market that can be used to drive the Hilborn injector setup provided that they are standard type electromechanical injectors. One such system is the haltech E6H or E6M ( http://www.haltech.com/Products/ECUs/E6H_M/e6h_m.html . Also if you are into DIY and like learning new things there is the "build it yourself" Megasquirt system (http://www.bgsoflex.com/megasquirt.html ). Of course there are other systems available but the Haltech has a REALLY good reputation and I think you will like the way the software works. The Megasquirt is being played with by a couple of internet buddies of mine and so far they like what it can do.

Abe

hello surfing around and found this site and joined.

I have two vehicles a 58 mga with the 3.9 fuel injected v6 out of a late model firebird running the compllete fuel injection system.

Also have a 47 fargo 1/2 ton (same as a 47 dodge) it has the origonal engine in it a 251 cube flathead 6 cyl.

i made up all new intake and exhaust manifolds for it and used the complete throttle body fuel injection system from a 92 chevy pickup the 4.4 liter.

running the stock computer and all the sensors. it was easy and i dont have to worry about tuning fuel and timing.

it is like the rotissirie commercial on tv, just set it and forget it.

the beauty of this set up it can be bought at most junk yards for 100 to 200 dollars. and the parts are readsily available at any parts store.

Here is how i did it, bought the throttle body harness all sensors and computer at a junk yard for 100 bucks
had a buddy machine an adaptor to convert the carb mount to the throttle body ( 2bbl in to one)

machined the chevy diistributor to fit the chrysler

installed a different fuel pump, ran a return line for the fuel to the tank and mounted all the sensors.

cranked it up ( not even two turns of the flywheel and it burst in to life) the engine ran about 2500 rpms for 15 seconds then the computer started reading all the sensors and it settle down to 725 rpm.

by the way i am a 58 year old guy, and it was not hard to learn, and it is easier than changing jets, and because there is no fuel wash on the cyl walls, i now have the best of two worlds, the beauty of an old flathead and modern efi and elect ignition so i now have a motor that will easily run 200,000 miles or better between rebuilds.

If i am in the mountains the computer knows it and adjust the fuel and spark as necessary.

in fact i was so pleased with the out come of the project that i ripped off the old restritive intake and exhaust. and designed my own.

went backt toe the machinist and had him make a new intale- exhaust flange out ot 3/8 steel, and had him drill - machine it with 1/2 " holes for the intake and exhaust tubes.
next i mounted it to the engine, and ran over to the local exhaust shop.

I had them bend me a set of 90 degree bends and then trial fitted them to the flange, and when i had it set i just welded it up. then i took it back to the muffler shop and had them make a collector for it.

now it looks like a tunnel ram intake and is awsome in looks and performance. the exhaust and the intake are equal length.

if any one wants photos or info i will provide it.

also the reason i used the setup from a 1/2 ton chevy pickup, is to save money, that vehicle down not have an anti theft built in to the computer.

hope this is of help,

John

danj , i have bought one of the hilborn setups for my new 33 .
this is one cool piece . it is a batch- fire setup so there is not many wires on it . i have aslo eliminated the hoses on the setup and made little billett plugs ,and machined the base to remove the name and fins out of it . it comes with a pump and filter computer all programed for this zz4 crate motor .
i am having new stacks made now because for the price of the unit it could have had a better stack .
just think dan at lousiville we will have 8 places to hide empty beer cans !!!!!