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MG MGB GT V8 Factory Originals Technical - Fuel Injection System ready

For all you members who have inquired. The Engine Management System for the Fuel Injected Small block 350 Chev, 4.3,3100 and 3400 60° V6 is now available. Thanks, Dann
Dann Wade

So... How is that better than a well tune carb or the regular FI for the V8 or V6?
Joe Walsh

This is always been a debatable subject. These are my opinions along with fact but I wouldn't care to debate the subject. The carb dinosaurs usually debate or downright argue about this subject. The problem when debating most haven't had the experience of using a good FI system. The FI systems I offer are mainly for persons who would like to use a modern GM engine swap for their project.

If you take every kind of driver and group the way they take care of a carburetor, or an engine, on the average then this is my way to explain why FI is better:

This fuel injection system may or may not be any better than what some builders use but it's based on reliable GM components not Lucas. I do know that Lucas does use some GM FI replacement components because their systems had failed often. I do know that I prefer it after many years of disappointments with carburetors. A carb always has to be retuned or a size change is in order or should be when your engine is upgraded.

When properly installed, fuel injection is better over a carb because:

Stays tuned
More economical and more than often makes more power than a well tuned carb.
Easily tuned or programmed should you upgrade your engine.
You don't have to guess it's all done for you, with one part using a replaceable chip.
Six billion cars have proven injection is superior.
Easy to analyze should a component fail.
Adjusts to altitudes automatically.
Few manifold explosions or back fires.
Easily adapted to fresh air systems.
Accepts Turbo or Superchargers easier.

ALSO:

No flooding, no percolation when the engine is hot which is what the V8 does best.
No water or rust in the bowl to freeze or clog circuits.
No float valves to leak,
No swelling of float(s),
No choke to contend with, no heat chambers to carbon up.
No moving parts to replace.
No sticking automatic chokes.
No choke cables to jam or rust.
No jets to change
No power valves to fail


Down side for injection.

Injectors may need cleaning after 150,000 miles.
Computer could crap out, but rare these days.

There are a lot of other reasons that I can't think of right now.

What advantages would a carb have over fuel injection? Very simple installation but not necessarily less expensive down the road.
Dann Wade

All well and good, but I'm not sure you addressed half of the original question: Is what you are offering better than the stock GM FI? Are you reprogramming GM ECU or are you offering a Haltech or some other setup?

The stock GM injection seems to be fine (once passed the wiring challenges) for a basically stock motor, while aftermarket allows a bit more...say a turbo kit or supercharger on a 3.4 for example.

Whatchagot?

Brian C.
NY

Brian Corrigan

and if you spend time siezed up in traffic- the FI system uses MUCH less fuel.

.....err perhaps not a consideration in the US where fuel is practically free.

Roger
Roger

Selected
World Gasoline* Prices
AVERAGE PRICES for JANUARY 2003

Country Price Per
Liter
In U.S. $ Price Per
U.S. Gallon
In U.S. $
Canada $0.489 $1.858
France $1.110 $4.191
Germany $1.179 $4.460
Italy $1.135 $4.294
Country Price Per
Liter
In U.S. $ Price Per
U.S. Gallon
In U.S. $
Japan $0.885 $3.348
Spain
$0.880 $3.329
United Kingdom $1.286 $4.865
United States $0.384 $1.453



--------------------------------------------------------------------------------

Multiply by 3.783 to convert price per liter to price per gallon.

For more monthly and annual international energy statistics, see the International Energy Agency monthly price statistics.
Additional world gasoline prices (weekly from 1996 to current) for a few countries can be found on the U.S. Department of Energy's Energy Information Administration's website at: www.eia.doe.gov/emeu/international/gas1.html

*Unleaded Premium (95 RON) gasoline for France, Germany, Italy, Spain, United Kingdom; regular unleaded gasoline for Canada, Japan and USA. All prices include taxes.


David

Sorry about that. I was trying to cut and paste and accidently sent the wrong item. Roger's remark started me wondering what world prices are. I guess the $1.96/US gallon I pay for 93 octane is cheap in the overall scheme of things. Taxes, though, vary tremendously from state to state. I sometimes buy gas in Georgia where it's $.30/gal or more cheaper. Sorry to stray from the original post.
David
David

David - the figures speak for themselves - my posting was prompted by my own experience of installing FI in order to reduce gas costs. The addon was not a dig - at least not intentional - it is a side issue here but it's difficult to get away from the exhorbitant tax levied on Fuel by the Europeans and the self-righteous sons-of-guns here who hold up US gas prices as the definitive example of profligacy.(I suppose their argument is equal cost and misery for all).

You won't find much of the foregoing on this board but it might help if most of us consider Dann's argument seriously. IMHO the lucas system ( a variant of a Bosch system) provides a more predictable result than Carbs. However the installation is quite a challenge the first time round.

Good luck to those who try

Roger
Roger

Brian, good to hear from you again. What I am targeting is the GM line and basically the 3.1 and 3.4 engines but a V8 or 4 cylinder set up is offered as well.

It is exactly what you was wondering about. It is a redone GM type ECU with 5 inputs and 3 outputs including the pump relay. It uses the very accurate DIS system. It is magnificently simple to install and takes out all the guess work in a MG conversion.

It does address the turbo system for a 60° V6 engine. I can supply a unit and harness or redo anyone's ECU and harness providing they have purchased the right components.

I cannot discuss prices here because of ethics.I can say that it is extremely compeitive to whats out there.Photos can be sent upon request.

Dann BCC
Dann Wade

Dan, a wet FI or dry FI? Different chip?

There a few pros and cons with fuel injection.
As for fuel economy FI is the way to go. Must of the fuel Injection systems were developed to operate in the low and low mid range were the engine operates at his normal output.

As tested: FI Vs Carb hp output, at top rpm the carb developed more hp and that is a fact.

The FI is much better in driveability,the sole purpose of mass fuel injection systems is to control fuel comsuption thus reducing emissions. The advantage is a control leaner mixture.
As for fuel boil over? Yes it can happen to a FI system, dry or wet.

It's great that you have a simplified system.
It sounds like a pigy back system to the GM ECU.
Bill Guzman

Bill, these ECU's are for use on the Multi Port Injection systems but I have ECU's that can be used with central injection systems using 1 or 2 squirters. Chips can be purchased from any vendor.

When you speak of "carbs" are you making reference to an ordinary street carb or an exotic aftermarket racing type.

Referring to MPI systems. Yes, you can get "boil over" but the closed injectors will not let the fuel get into the cylinders while the engine is at rest and exits out the fuel return line. The remainder will hold in the log manifold until call for. At a higher pressure from heat expansion there might be a temporary over rich condition. After a restart the fuel will be burned or expelled out the exhaust in a very rich condition. This will cause a very lumpy running engine but you could still get a restart a lot sooner then with a carb. Central Port Injection will act much like a carb since the runners will be wet with fuel.

A carb will cause a wet condition at the plugs at boil over and ground the ignition at the plug tips. If you are attempt a restart immediately you will pull in more fuel on top of what you already have in the cylinders aggravating the situation.

Not true with a FI system. If all other components are working properly the O2 sensor will detect an over rich condition and shut down the injectors.

The type of boil over you must be referring to is an extreme overheat condition and more than likely the engine has already suffered damage caused by the extreme heat. Regards, Dann
Dann Wade

Thanks Dann. I have experience boil over on a MPI Mazda Miata, where I lost power at wide open throtle at Ca. Speedway on a hot day in Aug car got to 250 and rpm's when down until it reach 230 BTW I was not the only one. Mazda rep was present. Yes you are right for normal street driven car it will never happen but a carb would have shut down completly.

No exotic carb, just Holley at wide open throtle on the dyno, engine a SBC 350 ci same test on a 302 Ford.
The FI that produce the best # was a MPI with a 4v TB mounted on a open plenun manifold, just like a carb.
The Chevy ran with 55 lb of injector pressure.

The MPI FI air runners are long and narrow which is why they are so good at mid range, where the carb is closer and has wider runners in the manifold (open plenun type)

Overall the FI is much better for the street, there is no argument on which is better for everyday driving.

It's nice to know that you have simplified the wiring.

Bill Guzman

So Bill, that's apples and oranges right? No reason a FI with equivalent runners would develop less power than a carb, right?

Jim
Jim Blackwood

Bill, thanks for the information. I'll file that information for future reference.

Jim, that's an interesting observation. That might be one of the reasons Ford places their throttle body nearer to center on the 302.
Dann Wade

Jim, any fuel system is dependant on the air/fuel track
and it does not matter if they are apples or oranges, what really matters is which one satified you the must,the end result is what really counts.
In the end a FI will deliver the best driveability
A purpose built FI (racing) can ofcourse deliver the same or a little bit more than the carb. this is on our world. On Formula One cars it's the only way to get the hp needed for that purpose.
So two fuel injection systems can be apples and oranges.
Carbs are still use in many racing sanction bodies due in part to the hp that can develop.
Pro stock racing uses carbs, Trans Am, SCORE, SCCA, and many others, I am changing my FI on my race car to 2 Webers 40 DOC or Mikunis These will produce the best HP in the top end with a sacrfice in the low end. This set up would be useless on the street. Same could be achieved with 4 independant TB and they would be more reliable than the carbs, but the cost of the FI is very high.
So I choose the simplest way to achieve the same with less reliavility (relative).
Bill Guzman

Yeah, that's about what I was thinking too. It's as much a complexity/cost issue as anything else, and the sanctioned racing bodies tend to have rules that favor one or the other. I like the driveability of the FI. Don't especially like the cost and complexity. But then, carbs aren't really all that simple either. And some of them are downright expensive.

Jim
Jim Blackwood

This thread was discussed between 15/09/2003 and 20/09/2003

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