maybe a dumb fuel injection question?

I dont know to much about fuel injection but my question is why cant I take the fuel injection off from a 300 from the injectors to all computers and wireing harness(port injection)and put it onto my 250 with minimal expenses? My thought is I should be able to take the firing order from the 300 and label each injector in corolation to that and then install on the 250 corolating the numbered injectors to my firing order and maybe just tune accordingly to my motor with use of a laptop.Seriousely I dont understand why this is not possible so any comments or suggestions toward this thought are appreciated( except for "thats a dumb question")thanks.I am just checking out all options for my car.I do plan to turbo my 250 this winter so please keep that in mind when sending suggestions.thanks again all!!

8) while it is possible to do just what you suggest, you will run into problems with a rich mixture even though there is only a 50ci difference in displacement. you are going to have tuning issues since the system uses a speed density system rather than a mass air system. a better choice would be to start with a megasquirt system, and work from there.

Not trying do dissagree but just dont fully understand that concept.I have already upgraded my ignition to electronic with blaster coil.I have a 1977 head from a 200 that has the 1.75 intake and now has 1.50 exhaust,its been ported and 3 angle valve job and exhaust been gasket matched so with a better exhaust and turbo with a mild cam I kinda feel it should be fine.Any more input to help me understand would be great because as far as megasquirt goes I know nothing about electronic circuit boards at all,and feel with my lack of knowledge I would mess up and waste my money .thanks again rbohm for your reply but do you think that after all this being done to the motor it would still be to rich and hard to tune?I only ask because I didnt give you any info and have me thinking you have asummed its for a stock application.

The stock ford ECU has a couple of shortcomings that the Megasquirt fixes. Adjustability, raw processing power, calibration for different sensors, you name it and the Megasquirt is a better choice. Buy a kit premade if you need to. And it is still cheaper than buying a stock ecu and a TwEECer to modify it.

Plus there are a lot of MS maps out there to start with...not sure about for the EEC.




That's my $.02.

Depends on the version of EEC.

The biggest problem I see is not just the 50 cube difference but the breathing ability of the heads. The 300 IIRC breathes alot better and can make use of more air and fuel than the asthmatic log head.

You could drag over the wiring harness for the 300 fuel injection and the ECU

A guy named Megascott makes a EEC IV to Megasquirt adapter that goes into the stock EEC IV box IIRC 1985 to 1994.

I want to drop in the Inline six into either my 89 or 91 Mustang convertibles. It already has EEC IV ECU and with the adapter I can plug Megasquirt right into the stock harness. Add Turbo Fairlanes TFI distributor mod and Im all but good but for wiring in the sensors.

You dont already have a computer harness.

DIY Autotune sells a pre wired harness that plugs into the Megasquirt that is labelled for what sensors go on the end. So easy even I can do it.

Scroll down to see harness
http://www.diyautotune.com/catalog/1239 ... -p-43.html

Whats your plan for fitting the injectors to the log? You will also have to make a custom fuel rail along with some sort of an adapter for a throttle body.

8)
Most people want to put the injectors in the intake runner, normally the best place, but the pics I have seen of heads with this mounting the injector shoots straight down into the runner, not at the back of the valve head.

I wanted to mount injector bungs on the far side of the log and mount the injectors to shoot down the intake runner at the valve head. Fuel rail would need to be fabricated and mounting tabs welded to top of log. Or go ultracheap and zip tie rails to the log

I have seen several places that sell universal injector bungs that can be welded or epoxied in place and billet aluminum bulk universal fuel rail that just needs to be drilled for injector plug in and ends added.

I would have a local head shop drill the holes and set the bungs for the injectors since the injectors need to be the same height.

Is this to be done with the log manifold, right?
How will you match fuel injected at each cylinder to airflow at each cylinder. The end cylinders draw less air than the center cylinders and will have an A/R that is richer than the center. Because the same amount of will be injected at each cylinder base on total airflow for all cylinders.

You said that on my thread too. So how about a plenum of some sort off the side like a constant diameter pipe or something in place of the log?

Thad":3lzc04fi said:

Is this to be done with the log manifold, right?
How will you match fuel injected at each cylinder to airflow at each cylinder. The end cylinders draw less air than the center cylinders and will have an A/R that is richer than the center. Because the same amount of will be injected at each cylinder base on total airflow for all cylinders.

Click to expand...

six, yes, six O2 sensors, one on each header tube
sexy

Asa":22o24pkn said:

Thad":22o24pkn said:

Is this to be done with the log manifold, right?
How will you match fuel injected at each cylinder to airflow at each cylinder. The end cylinders draw less air than the center cylinders and will have an A/R that is richer than the center. Because the same amount of will be injected at each cylinder base on total airflow for all cylinders.

Click to expand...

six, yes, six O2 sensors, one on each header tube
sexy

Click to expand...

Hey yeah thats the ticket I could...HEY...WAIT A MINUTE!

Could run smaller injectors on the ends to shoot less fuel at same fuel pressure as rest of rail.

I do like the larger plenum idea though.

I would run five or six thermocouples in the exhaust ports (depending on use - or not - of the Q'lifad paperweight), and match gas temperatures by varying injector pulse.

Rather like the way Gunson's ColorTune plugs were used to balance carb jets.

You would have to do a hack job replacing runners and log with equal length runners and a decent size plenum big enough to feed air to all equally.

Might as well go with individual throttle bodies and injectors. I have seen some snowmobile TB's that use a single bosh style injectors and can easily be ganged up for multi cylinders.

I think I will proabally stay away from the fuel injection till I know a lot more about it.I just liked the idea and the sound of having a 1970 maverick grabber thats port injected and turboed.But just to add a thought on some of your ideas why not just use 3 throttle bodied injections onto the top of the log instead of 3 carbs and use the o2 sensor in every other exhaust tube from the headers?

As far as I know there are no systems (OE or aftermarket) that actually can make independent adjustments to individual cylinders based on multiple sensor inputs like 02 sensors. The ones that have multiple sensors just average them and make general adjustments to all cylinders. Now I dont know that there would be any insurmountable issues other than cost and some software mods to use multiple ECU's for the various banks.

Turbo w/ port injection probably work with a log head. The air feed to each cylinder would be closer to equal under boost.

If you are going turbo anyhow, why not just use a GM TBI? Modifying the log to adapt a carb or TBI has been done to death, so you don't have to reinvent the wheel. The TBI can handle a few hundred HP and you can always add an auxiliary injector in the inlet tube for those high-boost runs. Simple, effective, cheap.

regarding your idea of using a triple TB setup, which i've been pondering for an NA application, I guess Id be concerned that boos might force the secondaries open prematurely while you are cruising around. Maybe heavier throttle springs would remedy this, but could it be a problem?

While running multiple TBIs is usually for high RPM apps, it is do'able, but usually the computer(s) don't control ignition timing, only the fuel mix....running 3 TBIs with 3 separate O2 sensors, means running 3 computers(independently) to get most accurate measures....and they are usually NOT car computer systems, but are large ATV systems....altho running 3 systems from a Honda 1100 is desirable, the cost involved in attaining the parts is out of this world.