MegaSquirt: Sticking it to the man...

[Jon K]

So here I am at school still, nothing to until tomorrow morning when I take my last final exam. Once I am done, I am going home to pick up saj3n's car to do a radiator and struts for him over break. Once back from that, I will put on some music (I am thinking Mendelssohn or Liszt for now) and begin building my MegaSquirt standalone ECU.

Being that I am bored, I decided to look up this Grassroots Motorsport article Bahnstormer had talked about a while ago regarding MegaSquirt. So, here I am reading it, I am about 25% through and realized this is not only informative but also a good read. So, I decided to share with you guys because I know a lot of you are not exactly sure what MegaSquirt is, what it does, and how much it costs. People hear "Standalone fuel management" and think 2- 3- 4 thousand dollars. Wrong. So here is the article - I find it quite entertaining, informative, and motivating :)

http://www.grmotorsports.com/news/102005/megacapable-beating-the-man-with-diy-fuel-injection-from-megasquirt.php

[winfred]

i am thinking about building a ultra megasquirt for the e30

[Jon K]

The Ultra is not out yet but rumor is that it will be soon. I am using a MS v.3 with MS-II add on card later. Something worth noting is that they yielded 100whp initially with just the MS installed. Once they had it redo the AFR's, it yielded 117whp. The 100whp was +10 on their previous test, and 117, is then, +17 hp, just in a preliminary tweaking. Very nice.

[winfred]

that's why i am still thinking :D i've been watching for over a year for the ums to come out as i am not in a hurry


The Ultra is not out yet but rumor is that it will be soon.

[Jon K]

is there a specific reason you need UMS over MS-II?

[Booster]

My boss's friend in ST' Louis Mo. has been doing Beta testing with them for some time now. Its convinced him to run Mega on 3 of his cars.3rd gen RX-7,1st gen RX-7 and his sons 2nd gen too ! ALL of them turbo and injected 13B's.
I figure what the hell......I'll do it on one of my Turbo Datsun 240-Z's just to simplify the older 3.0 litre modded electronics that tend to have Gremlins from time to time.
If I like it enough.....I'll do another one for my 525I turbo instead of just a chip and additional injectors. Would be more efficient for sure.:D
.............Vinny

[kyleN20]

to intense for me, i woild def need help on this portion of turboing. but why cant you just use standard FI, it seems like this is for taking a carbed car to EFI, why not just stick with what you have if you already have EFI. and i am truly asking this question, not making any kind of statment.

kyle

[Jon K]

I don't think you fully understand what it does. It is a EFI controller. Our cars already have one, true. The MS is a EFI controller for cars without EFI. But more than that, it is a programmable EFI controller. You plug your laptop in, and with various sensors, are able to dial in more or less fuel/timing/spark. You can use "standard FI" (I think you mean the stock Fuel Injection computer) if you get a chip burned specifically for your application - but few tuners offer that and as far as doing it yourself, you need to know how to read hex code and where in the hex dump the fuel maps are etc.\

The alternative is running a chip - you cannot (although FMU/RRFPR work, as I have right now) just turbo your car flop some big injectors on it and go. The stock ECUs have no idea what happens with boost as they are not MAP activated. They also don't have the necessary fuel maps to be able to scale injector pulse width down. Let's play a numbers game. Let's say 19# injectors on an M30 idle (this is totally hypothetical) 12 millisecond pulse width. You go and stick 30# injectors in to support your boost, the ecu says - based on the O2 readings - "wow this car is running rich" (obviously, larger injectors...) so it tries to make the pulse width as short as possible (amount of time the injector is open) but maybe it can only go to 10 millsecond pulse width, but the car is STILL rich because of higher flowing injectors. The injector size may require a 7ms width, or you may simply have to raise idle to add more air, the ECU, without a chip, is not able to do any of this - it can only work in it's programmed tolerances.

[kyleN20]

muy interesting, do you have to be skilled in computer know-how in order to set up a system like this? like you were saying, with all of these unknown tolerances, its possible that a stock ecu cant down tune it enough, but it would seem to me that making your own ecu would be "harder"?? wouldent having a chip burned for you be cheaper? and when you do set up your own MS system, how do you know yourself what to set pulse width at and such?

thanks for the info

kyle

[kyleN20]

muy interesting, do you have to be skilled in computer know-how in order to set up a system like this? like you were saying, with all of these unknown tolerances, its possible that a stock ecu cant down tune it enough, but it would seem to me that making your own ecu would be "harder"?? wouldent having a chip burned for you be cheaper? and when you do set up your own MS system, how do you know yourself what to set pulse width at and such?

thanks for the info

kyle

[Jon K]

muy interesting, do you have to be skilled in computer know-how in order to set up a system like this? like you were saying, with all of these unknown tolerances, its possible that a stock ecu cant down tune it enough, but it would seem to me that making your own ecu would be "harder"?? wouldent having a chip burned for you be cheaper? and when you do set up your own MS system, how do you know yourself what to set pulse width at and such?

thanks for the info

kyle

You need to know background information involving gasoline engines. For instance, your AFR at idle should be between 14.5 and 14.9. So you set you initial idle fuel keep an eye on the wideband O2 and see that the engine holds idle. Once you tweak it, they usually idle smoother than stock!

There is software that automates VE fuel maps and you datalog (collect info regarding all sensors and stats) and read that into MegaTweak, where it "thinks" over your log, and optimizes the settings.

To get a custom chipped burned for your specific car usually costs around $1,000. If you make a single change... lets say boost level, new injectors, front mount intercooler... then you need to get reflashed. MS w/ wideband controller and all necessary cables/connectors/everything, $530 to my doorstep.

[Paul in NZ]

very interesting indeed.....In NZ we didnt get unleaded fuel until the mid nineties,so every e34 came without cats and o2 sensor.I think that we also have a outdated "map" fi system to go with that.In your OPINION Jon do you think a megasquirt system with a retro fitted o2 sensor and maybe an ignition system would improve the efficiency of a otherwise std M30(prolly more like a US e28 m30).As an aside what does the M30 have as an ignition system,I know it has the dizzy and rotor,what about the rest?

[DCR]

Plenty of the guys (particularly the E30 lads) on www.eurocca.net are running the megasquirt set up. It is definately something to consider.

[Jon K]

very interesting indeed.....In NZ we didnt get unleaded fuel until the mid nineties,so every e34 came without cats and o2 sensor.I think that we also have a outdated "map" fi system to go with that.In your OPINION Jon do you think a megasquirt system with a retro fitted o2 sensor and maybe an ignition system would improve the efficiency of a otherwise std M30(prolly more like a US e28 m30).As an aside what does the M30 have as an ignition system,I know it has the dizzy and rotor,what about the rest?

Almost any time you can add accuracy in your fuel tuning, you will see gains in either performance, economy, or both. Yes, if you added an O2 sensor (wideband) ditched whatever EFI system you have now, and put the MS in, you would at least be able to have better economy and more than likely if you have no O2 sensor, the ECU runs in a richer mode, so you will probably see a nice power output as well.

M30's over here, E34 at least, have a distributor, coil, 6 injectors on the intake, an AFM for metering air, and an idle control valve, and narrowband O2 sensor.

[Paul in NZ]

ours are the same save the o2 sensor and probably a different ecu

[Jon K]

Because the M30 uses a single coil and a distribituor, you can take full advantage of the timing/spark control... and have FULL standalone ecu. On my car, intially, it will be standalone fuel only.

[Sean H]

Good stuff. I have a set-up here waiting to go on my 318 in the not-too-distant future.

[bahnstormer]

what are u using for your TPS? or just a MAP sensor?

[Jon K]

what are u using for your TPS? or just a MAP sensor?

Tap stock tps

+ map

[winfred]

it's been a while i looked at it and can't remember what pushed my decision to wait for ultra, it was something that caught my attention some feature i want. ill check out the site and see if i remember


is there a specific reason you need UMS over MS-II?

[bahnstormer]

m50 has a tps?

[winfred]

yep it's a rheostat style and ranges 0-5 volts


m50 has a tps?

[bahnstormer]

damn

for the m30 i hear i'll need to retrofit a automatic traction control tps... that sound right?

[Jon K]

you just need a TPS that does 0 - 5v. GM part#

[Paul in NZ]

m30 tps basically on or off right??

[genphreak]

m30 tps basically on or off right??Yep, but the GM part is an easy replacement, however the MAP sensor is a harder add on if you have to position it at a particular location on the intake manifold- still not sure if hanging it off the brake booster port would make it fluctuate at all (from booster sucking out pressure - surely the localised vacuum changes would be minimal, but its the first place to try... :) Nick

[winfred]

m30 with traction control has no tps, eml does everything, automatic has a rheostst but i am not sure if it's useable


damn

for the m30 i hear i'll need to retrofit a automatic traction control tps... that sound right?