Upgrade your L-Jetronic ECU

[Guest Uncle Woja]

Hello everyone.

 

My TR7 V8 has the old L-Jetronic injection system on it. For those of you who don't know which one the L-Jet unit is, it's the "flapper" type air flow metre.

 

Needless to say this system is woeful in its performance. So I am building a new ECU called Megasquirt.

 

It is a kit ecu. you buy the kit and solder it together yourself. Mine is together but not in the car.

 

I am mounting my new Megasquirt in an old L-Jet box, using the old L-Jet plug. That way it's an easy swap and no cutting of looms and figuring out if that 30yr old wire is cream or white?

 

I just thought I'd drop this forum a line and let you know of my project if anyone is interested.

 

For thos of you who are interested, the whole ECU has set me back about AUD$200. It is banked injection and works on MAP. It is fully programmable and there are variants out there which control spark. It can use either an 8x8 or 12x12 VE table for fuel calculation and a 12x12 spark advance table if you want the spark controlled.

 

If anyone is interested, I can give you as much information as you need. As funds are a little lacking for me at the moment, I am unable to get a before and after power graph done on my car to show what difference the Megasquirt makes, but I am expecting big things. Mainly better economy than 18-20L/100Km (or 12MPG for the people in the US) which I am currently getting from the old L-Jet unit.

[Guest pilbaratr7]

Hi,

I am also going with Megasqiurt for my TR7 V8 conversion with a Rover 3.9 EFI V8. I have just bought the Aussie "Stew" Stimulator and placed an order with the Aussie group buy, should get the parts in 2-3 weeks. :-)

Will be good to up grade  to MSII when that comes out. I will also be looking at buying a Wide band O2 controller from Techedge.     http://wbo2.com/

I also just bought a second hand laptop computer off ebay($250)  so I can tune it in the car on the run.

You will have to let me know how you go with tuning etc when you get it running.

 

http://www.msefi.com/

 

Regards

Glen.

[Guest Uncle Woja]

Well, I got my Megasquirt running on the weekend. I wasn't game to start cutting wires to join in new sensors, just in case my Megasquirt didn't work. Then I would have been without a car for god knows how long.

 

I'm pleased to say that it fired on the first stroke. Much quicker than the old L-Jet unit, and that was with only using the default settings.

 

I didn't do any tuning other than getting a stable idle. Over this week I will calibrate coolant and air temp sensors, take off the AFM, make a new air intake out of PVC and then I'm good to go.

[Steve]

Can this "Megasquirt" be installed on the 4 cly injection engine?.

 

Steve

[Guest pilbaratr7]

I would say yes.

 

Q. What is MegaSquirt?

 

A. MegaSquirt is an experimental Do-It-Yourself programmable electronic fuel injection controller that will work on virtually any liquid fueled spark-ignition engine. Note that MegaSquirt is the controller only, you will have to gather the remaining fuel system parts yourself (from 1 to 16 injectors, sensors, fuel rails, fuel pump, etc.).

Experimental means that YOU are responsible for sorting out some details of your fuel injection that are specific to your application. Do-it-yourself means that you save money by assembling it yourself with a few basic tools and comprehensive instructions.

 

MegaSquirt will work on one to 12 or more injectors, of high or low impedance, and for any number of cylinders, even three and five cylinder engines and odd-fire engines.

 

Check out these sites:-   http://www.msefi.com/   http://www.megasquirt.info/

 

Glen.

[Guest Uncle Woja]

It can run anywhere from 1 to 12 injectors. It is banked injection, but this does not effect power in any way compared to sequential.

 

Actually, when you work it out, sequential injection works almost the same as banked injection above 2300RPM.

 

Now, an update on my project if anyone is interested.

 

I have my MS on my car and running. It's actually running pretty bad in the high revvs, but I think this is due to the fact that I have  stuffed around with the fuel map without knowing what I was doing. I'm going to start from scratch this weekend.

 

Even with the very rough fuel map I have now, power is noticably better in the low revvs. Once it's tuned well, I'm expecting some neck wrenching acceleration through the 3.9 diff.... assuming the tyres will give it to me.