Megasquirt - The FAQ

MS only does batch injection, not sequential, so you can in theory run as many injectors as you like (providing you make precautions to deal with the flyback voltages you'll get running that many). There is an add-on board for the MS that offers much more robust flyback protection if required.

MS has two injector banks, which can be configured to fire simultaneous or alternating off the same VE map, or they can be run off separate tables with various different configs to allow injector staging, independent bank control on V engines etc. You can also use one bank for fuel injection and the other to control something else, water injection for example.

 

next question is....Can i weld the lambda down at the collector to prevent me having to remove my 4branch??? Guna start with narrowband 1st(then upgrade to hairband,then rubberband )

 

That's fine as long as it's a heated sensor (i.e. 3 or 4 wire).

 

Excellent post Martyn, may poach some of your settings and see how it goes on mine. As for fuel rail, I used a rail from a Mitsubishi "magma" engine, think it was a 1.6and also found in some Protons.


Steve.


http://www.golfgti.co.uk/viewfeature_content.asp?featureID=3 0

 

Interesting! so this rail lines up then with the 16v manifold?

 

Some great reading there, wish I`d of gone for megasquirt from the start now..

 

what are you using

 

Thought this was guna get sticky'd?

 

another vote for sticky

 

Using digi1, choice now is either to use an SNS chip with it or bin the lot and fit Megasquirt`n`Spark...

 

How is Trev getting along with reverse engineering the digi 1 ecu/coding?

 

Don`t know, havevn`t heard a lot from him recently, still got his ECU that I need to post back.

A bloke on Vortex claims he`ll be releasing a program to alter the fuel maps quite easily, we shall see..

 

Do you have a link to that?

I've edited the first post to include the spark stuff, and a few useful links. I've also updated the spark map, i'm running more advance at idle now in a vain effort to make up for the lack of ISV.

 

a very very good post

could this mega squirt be used for running a 1.8t conversion or is this too much of a head ache for it(or me)?

 

dont take this the wrong way as i know F all about mega squirt but why would you fit this?

does it alow you to adjust things that cant be adjusted with normal k-jet?

also if it does let you fine tune more, have you had it on the rollers before and after?

 

With K-jet the fuel map (amount of fuel to squirt) is largely fixed by the shape of the cone in the fuel metering head. Although you can make some adjustments to the fueling on k-jet you can not fundamentally change the fuel map (cone shape). Megasquirt (or any other programmable electronic fuel injection system) allows the fuel map to be tailored to suit the engine.

 

Also,when converting to forced induction or itbs the need for fuelling is increased past the limits of k-jet.
Should be able to run a 20v on it aswell! make wiring it up alot easier i would of thought

 

I went for Megasquirt because a) i was interested in fitting bike itb's and having to route airflow through the k-jet metering head would waste any gains I may have seen, b) it's different (even more so when I first started looking at it), and c) i'm a tinkering gadget freak who can't leave anything alone

Haven't had it on the rollers yet, other things keep getting in the way (like the first car dying of rust, and this one's rad fan dying ). I do want to get it down for a mapping session with a decent operator, just need to get everything else ready first, then start speaking to places about it.

How is boost controlled on the 20vt? That's the only sticking point I can think of, boost control in MS is a bit primitive at the mo, you may want to consider it carefully. There is now support for toothed wheel decoding (I assume the 20v uses a 60-2 crank wheel like the ABF etc?) and four ignition outputs for coil on plug, but again it's in the very early stages of development so you'd be having to work out how to drive the hardware yourself. Definitely not plug and play

 

Finally got my Megasquirt kit! wooohooo!

My setup uses an ABF manifold, throttle body and fuel rail fitted to a 9a lump in a 16v mk2 Golf keeping the ISV. I have a few observations for this setup which may help others.

Manifold Fitment Issues

There are a few issues with the fitment of the ABF manifold to the 9a.

The fuel rail / fuel pipes will not clear the upper alternator bracket. It is fairly easy to modify the bracket with a bit of cutting and welding.

One of the lugs on the cam cover is very tight against the fuel rail and needs grinding a bit.

The lower section of the manifold does not clear the water outlet flange on the head. A bit of careful grinding of the flange and the manifold is required to get clearance. Be very carefull though as it is very easy to break the flange when tightening the manifold on if it does not clear it.



Fuel Connections

Using the fuel pipes from the ABF fuel rail presents a challenge in terms of finding a fitment to the M12*1.5 fitments on the 16v fuel lines. I got some made up at Hydrasun. They hacked up two different fitments and welded them together. I am sure they said that the M12*1.5 fitting is termed a 6L fitment.


Electrical Considerations

I have still not been able to find a connector to fit the throttle position sensor on the ABF throttle body.

The ABF throttle switch is a two pin connection and not three pin like the 16v one. You need to find a two pin connector which fits and connect up the two wires from the three pin connector which form a circuit when the switch is closed.

**Note** this is only required if you are keeping the ISV. Since the ABF throttle body has no idle bypass built in you probably would want to though.


Sensor Sharing

Since I was keeping the ISV I decided to share the coolant sensor used by the 16v ignition ECU. To do this I did not fit the bias resistor for the coolant temp sensor on the Megasquirt board. I then hooked the sensor wire from the Megasquirt straight to the sensor. It is necessary to identify the bias resistor used by the ignition ECU and to then use this with Easytherm to update the Megasquirt. I found the Ignition ECU bias resistor to be around 9.9k ohm but it would be best to check your install.

The only problem I have had so far with this set up is a mildly fluctuating coolant temp sensor reading. I think this is due to the large bias resistor in the ignition ecu. This causes a very small voltage to appear across the sensor which I think causes the fluctuation due to resolution.


Thanks for posting your ve map up Martyn_16v it proved a good starting point.

 

Nice one That's two new MS installs already this week, any more?

I think the ABF water outlet is only 7 or so from VAG, might be worth a look if you're not too sure of the strength of the modded 9A one. I also had similar issues with the fuel lines, I got an adaptor for M12 to -6JIC, then had the lines made up from there (all from Think Auto).