Thread: Aftermarket EFI Questions - Please help

You can buy megasquirt kits assembled for about $300 au. see here http://www.diyautotune.com/catalog/m...d253e39c8586c7
Its very cheap and relitively simple to install.
Bit of mucking around setting it up with your laptop but good fun. see here
http://www.megamanual.com/ms2/tune.htm
I just finished EFI ing my p76 4.4 in a 2door rangie.
Highly recommend it.

My computer isn't a microtech its an AIRSENSORS injection system. Basically it is an injection system that replaces a Holley carb, It has a throttle body that goes on to were the carb would be with 4 butterlies that have an injector in each of them. It uses all the original throttle linkages from the holley carb, essentially this is the problem with running a TPS. It has a hotwire aiflow meter and it takes a coolant temp and an rpm count. I will try to post a few pics when i get back to my own computer. I just want to replace this computer with a new one I dont want to replace the injection setup. Also it just needs to control the fuel, Will the megasquirt do this?
Thanks

Thomas

Yes
Megasquirt can be set up to control any thing that requires a pulse width (ie an electronic injector)

Cool thanks, I will speak to a few more people and see what sort of costs are involved in each one. One other question will it be hard to find a program to do this sort of injection setup for the megasquirt. Although i geuss any program for throttle body injection on a chev motor would work (this injection setup was originally made for 500 cube chevs).
Thanks

Thomas

Have you looked at their site?
http://www.auto-nomics.com/faq-all.html

According to their site they have a TPS and a MAF.
Interesting , I have never heard of one or seen one before.

I was looking to see whether they had a diagnostic. Maybe if you emailed them they could send you a test procedure. It may only be a relay or something.
A Megasquirt could be set up to read the TPS OK, and if you know what you are doing the Megasquirt could be set to the existing sensor values.
A megasquirt usually uses a MAP sensor not MAF. The Airsensors is the only aftermarket system I have seen to use a MAF.
Whichever system you decide on It will cost you more than you think.LOL.

I was recently quoted $3000 to "turn key" fit a Haltech by a company in Mona Vale, where one of the guys helped design it.
You have to factor at least 1 dyno session, if you want correct full throttle mixtures.
If you are starting from scratch , you would get a much better result with an injection manifold, and using wide band O2 sensors, so that you can choose your AF ratios for economy and/or power. Megasquirt can do all this, but remember you cannot call on professional help, only from an enthusiastic band of amateurs.
Regards Philip A

Yes but i didn't see that page. Mine doesn't have the TPS the one they are talking about there is a digital manifold mine is an analog manifold it has no IAC or TPS. My computer is the first picture with the MAF sensor being the analog 4 inch one. I am going to send them an email seeing what they can do for me, Fingers crossed. Thanks PhillipA very much you are a legend thanks for finding that. we will see how we go.

Thomas

I have have installed and tuned a Wolf system in a V12 Jag for afriend, controlling both fuel and spark, and I am currently building a Megasquirt 2 for my own V12 Jag to control ignition, bt I'm keeping my modified OEM style ECU for fuel as it works well.

The megasquirt is quite simple as far as kits go, the instructions are really clear (unlike the Jaycar kits that require you to know a bit about electronics) but a short answer, unless you know how to solder properly, forget it. If you can build a decent electroinc kit and get it to work first time, then have a go.

Whilst I have not had time to finish the kit ( I'm too busy playing with the Dicovery and the XJ-S is running great)

I bought a kit, a pre-built and tested stimulator ( that way I know it's my if it doesn;t work, the wiring harness and all the right tools ( temp controlled soldering iron, magnifying light, etc) It cost me about $550 so far. I also bought a Wideband 02 sensor data logger to tune the car - that cost $300 and built a remote mircophone to listen for engine knock whilst driving

The Wolf system I installed started first time, I used WOlf's map but since we had different injectors ( 3 times the flow rate) I had to re-write the map. I set it up to run a bit rich so I would not blow his engine, it ran OK but needed some more precise on road tuning with the wide band O2 sensors with we did not have at the time. My friend then decide to rebuild his car - fit almost a new everthing, motor, tranny, suspension interior etc etc, so I had to repeat the whole exercise again 12 month lated but this time on a 6 litre V12 with different injectors. Again I got it to start first time, but it also needs a bit of on- road tuning. We were going to spend a day or two tuning it out on the road, but I have not had the time so he has taken it off to be dyno set-up, afterward we will tune it more precisely on road

Unless you can do it yourself, a trip to the dyno for a tune will set you back $1000 at least, and then it will be running rich as the dyno guys don't want to risk you sueing them for melting your engine. The dyno session are just the start, on road tuning is a necessity ( remember OEM manufactures spend 100,000's of man hour all around the world to make a proper map for a car, not 6 hours on a dyno. I've seen some terrible maps, whilst they work great at full throttle at 30 deg intake temps, the can melt piston cruising down the freeway in 40 degree weather or idling in traffic constantly wash the oil of the bores leading to early engine failure.

In short, if there was an OEM ECU for you engine, use it, it will work, but if you are confident in setting up and tuning the iginition and fuel on a car, and have all the right sensors to know when something is going wrong, then welcome to the DIY Megasquirt CLub .

Thanks Iain, Im still trying to work out what I want to do. The company who built the computer and injection still sell remanufactured ecu's for $200 USD so I might go for that although my mate who runs his own workshop and has a lot of experience with installing and tuning Microtech's and im thinking of going this way as they are more reliable and easier to tune than the old style of ecu that I have now.

Thomas