Grassroots Motorsports Magazine had an article about open source Mega Squirt
in the Oct 2005 issue Page 89.
www.grassrootsmotorsports.com

It is far more highly developed than I thought.
It is low cost and has some real nice features like data logging.
It is not for everybody. You should at least have some electronic
tech expierence. PL

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"MegaTune is the open source (and, once again, free) Windows-based application used for tuning MegaSquirt. The design is easy, intuitive and very well documented. It's solid as a rock, yet purposely designed to run on some of the slowest laptops you can dig up on eBay.

Like other examples of well-built, open-source software, it works well; it's also as powerful as any proprietary tuning software on the market. Eric Fahlgren, the designer of MegaTune, is constantly improving the software in response to the requirements of the hardware designers and requests from users.
We programmed our Innovate Motorsports wide-band oxygen sensor to produce an analog signal between zero and 5 volts depending on the air/fuel ratio. This signal was then fed through our MegaSquirt ECU and into the laptop for data logging in Mega Tune. This made tuning painless and guess-free. .

There is a Unix equivalent of MegaTune; written from scratch, it's called MegaTunix and is designed for use with Apple and Linux operating systems. This excellent program has helped fill in the gaps for people who don't have or want Windows-based laptops.

Others have made important software contributions to the MegaSquirt project. MegaTweak is a program that takes MegaSquirt data logs and does some serious statistical analysis of what an engine is doing, essentially tuning your car for you. MSLV (MegaSquirt Log Viewer) is another application that uses data logs to play back driving sessions like a movie, helping the right-brainers visualize what MegaSquirt actually does.

Steve Berry, our Volvo and MegaSquirt expert, likes the sharing nature demonstrated by those involved in the project. "These are some great examples of how an open community adapts and fulfills the needs of its users with no profit motive in sight," he says. "This kind of hippy 'gift culture' may seem strange to anyone not familiar with the open-source movement, but the end results speak for themselves."

Once we had MegaTune loaded on an old laptop, we plugged into the MegaSquirt ECU and started programming the basic settings. One concept that is used in MegaSquirt tuning is the VE table. VE stands for Volumetric Efficiency, a representation of cylinder filling in relation to manifold pressure."

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From my experience this is an easier way to tune the engine before you
fly with it. Of course a lap top will not fit in the front cockpit
single pilot. But I see no reason why two people could not tune the
engine in the air.

Mega Squirt also uses a throttle position and water temp sensor in addition to air temp and MAP for better control over transient  engine condition.
I notice Dave Leonards engine runs a bit rough during throttle transients.
Not at all like my RX8 :)

It will also work with the ignition of your choosing so you could
run MSD capacitive discharge for its ability to punch through lead
fouled spark plugs. PL

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"The future of MegaSquirt
Although MegaSquirt was qbviously well designed, as shown by the new features people have added since its inception, the processor is a minimal 8-bit one that is nearing the end ofits expansion capability.

To answer the need for more power and capability, Bowling and Grippo have developed MegaSquirr-II, which uses a 16-bit processor with three times the speed of the original MegaSquirt and a lot more memory. This processor is easily capable of accurarely handling spark control as well as fuel and idle speed COntrol.
It is also large enough to increase the number and size of tuning tables for fuel (including tables fot tWo sets of injectors) , spark and wide-band oxygen air/fuel targets, all as a function of rpm and air pressure. According to Bowling, "the nicest thing about MegaSquirt- II is that the processor and some additional hardware were laid out using surface-mqunt technology so they fit on a small daughterboard, which can be plugged into the existing processor sockets on the old MegaSquirt boards."

Upgrading from old to new won't be too hard, says Bowling: "All that is required is to wire in spark and idle motor, if you want these, and you have upgraded your system to MegaSquirt-II, no other wiring changes required."
The future of MegaSquirt is just around the corner, Grippo adds. "We have finished beta testing of the MegaSquirt-II board and we are expecting the first production mn to arrive any day now. When they do, we will start selling them and users are chomping at the bit to start adding a new round of improvements."
Like the original MegaSquirt, Grippo sees the basic MegaSquirt-II architecture as only a starting block for the DIY tuner. "We will see how far the users take these," he says. "We know there are people out there making transmission controllers, traction control boards, and who knows what else that can easily interface with MegaSquirt-II. We, ourselves, have a pretty sophisticated wide-band °2 controller that we can throw into the mix."

Bowling adds that the new system will maintain the MegaSquirt traditions: "Our philosophy will continue to be open source development, fair prices, and continuous incremental improvement."


Assembled MegaSquirt ECU: $250 assembled MegaSquirt relay $90 board:
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Web Sources.

Bowling and Grippo www.bgsoflex.com/megasquirt.htm I developers of MegaSquirt

DIY AutoTune www.diyautotune.com MegaSquirt retailer

Innovate Motorsports (949) 388-4442
www.tuneyourengine.com wide-band oxygen sensor

MegaSquirt   www.megasquirt.info
MegaSquirt boards and information

MSD Ignition    (915) 857-5200
www.msdignition.com
capacitive discharge ignition

PerTronix (909) 599-5955 www.pertronix.com ignitor





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