mega squirt

[Sam Matthews]

I know there are some of you using this system what model and where did you purchase plus are there any available preset starting maps? Any help would be appreciated Thanks Sam

[Ken911]

DRmatera is a big help he did his with a mega squirt, and it turned out really well.

[911nut]

If you do a search you will find a lot of info covering various approaches to implementing megasquirt on turbo and n/a cars. Be prepared to spend 3-4 hours reading it all!

[sjf911]

I started with MS2 then upgraded to MS3 followed by the addition of MS3X when it became available. MS3/MS3X offers a huge amount of flexibility over MS2 but comes at the cost of complexity and an OS that is still being developed. Neither provide adequate knock provisions but the MS3/X lends itself to use of the J&S for COP or CNP knock control.
Going to sequential injection/ignition where the MS3 really shines requires adding a cam sensor which is not impossible DIY by modifying the air pump drive or the distributor but probably easiest done with Clewett's combined scavenge pump/cam sensor unit which is not cheap. Converting to the 964/993 oil filter and using the right hand cam for the standard sensor is also possible.
You need to decide what level of control you want and let that dictate which system you get. You can get >90% from MS2 with a lot less build hassle. DIYAutotune is one of the main sources for components but BoostEngineering is useful for Ford EDIS components if you go that direction in ignition and Clewett is indispensable. I am running Clewett crank and cam sensors with his crank pulley/60-2 wheel combination. The MS3/X ECU is from DIY as is the MS2 harness. I had to add an additional harness for the MS3X but made that myself although it would be cheaper to get one from DIY now that they are available. IIRC, I sourced my LC-1 from DIY as well.
Base tunes are going to vary from car to car so much that I wouldn't start with someone else's tune, except for conservative timing. Dyno time is really helpful especially to confirm timing and the accuracy of your wide-band O2 controller which you will very heavily rely on for tuning.

[911nut]

Steve, great info.
Was MS3 a lot more difficult to tune compared to MS2?
Are you using COP?

[sjf911]

MS3 without MS3X is very similar to MS2 so not much tuning difference although larger tables. MS3X adds sequential control as well as a host of input and output ports which adds a lot of wiring. Also, with MS3X comes a lot of other things that are easier to implement compared to MS2/MS3 such as open/closed loop idle control, AC control, open/closed loop boost control, fan control, launch control, etc., some of which require a lot of closed loop tuning. You also get vehicle speed and gear specific functions and a lot of user settable items.
I am currently running full sequential injection/ignition with 12 LS2 D585 coils in a CNP twin-plug setup. I am only running open loop warm-up idle control right now with a 3-wire Bosch valve that is stock to the 3.2 but have played with closed loop tuning which I will ultimately migrate to to allow AC idle up and load dependent AC shutoff (I pre-wired the AC system with this in mind). I log all of the normal engine parameters as well as pre and post IC intake temps, vehicle speed, gear selection, mass air flow (with a Ford blade style MAF between the IC and throttle body), and methanol injector flow via a CoolingMist injection controller with in-line flow sensor. I have a manual boost controller but this system can be used to do electronic boost control with the addition of an appropriate PWM valve which I have pre-wired for but not hooked up. This would allow for significant failsafe operations based on EGT, O2, or knock feedback. You could also control water/methanol injection with this setup.

[Sam Matthews]

I have some work ahead first is more research and then to make an informed decision as to if I am ready to take this project on Thank you for the information Sam

[xbmwguy]

i just finished my ms2 conversion and this is my 2 cents...the ms2 is leap years away from cis as would any efi, and as sam stated the 3 can do a hell of alot more than the 2 but as inexpensive (compared to the big names) as these are my goal is to start with the 2 and get to know the software really well then maybe the 3. we will see but the 2 is a great system. you will like it

[fletcher0780]

take a look at VEMS while you're researching, it is a pretty amazing and inexpensive system. I'm currently in the process of converting to EFI and am going to run VEMS.

VEMS website: VEMS v3 ECU | VEMS US
EFI express (VEMS tuner/distributor): EFI Express : Home

[turbo nut]

I to started with MSII and switched MSIII. If your going to us Megasquirt in my opion just go for the MSIII and MSIIIX to begin with or at least build the wiring harness with all the extra connections. I like the USB connection and SD card datalogging. It took some time and ALOT OF FUEL to get it dialed in but am very pleased and have learned a ton in the progress.

[sjf911]

MS3X more than doubles your wiring harness size and complexity, so I agree that if your plans are to go that route even if delayed you should wire it in advance. I tried my best to anticipate what I would need or might need so that the wiring is there. I prewired for boost control, AC control, MAF, multiple IAC options, future sensors such as the pre-IC temp, etc. When I started with MS2 I used the megasquirt relay box in the engine compartment but when I switched to MS3X, I rewired the engine electrical adding a Bussman 15301 RTMR relay and fuse panel with a 90A main power circuit breaker. I never liked the MS Relay setup. Also, it is easiest to run your harness with the engine and tranny out of the car.

[TurboKraft]

Originally Posted by sjf911

Going to sequential injection/ignition where the MS3 really shines requires adding a cam sensor which is not impossible DIY by modifying the air pump drive or the distributor but probably easiest done with Clewett's combined scavenge pump/cam sensor unit which is not cheap.

Almost every 1974-94 911 Turbo came with an air injection pulley & housing. You can add a hall-effect synch sensor for well under $100.

Example:


Using a mag pickup (ex-Electromotive TEC3r engine):


Mount the sensor to the housing perpendicular to the pulley. Drill & tap the pulley and install a ferrous bolt with a drop of blue Loctite. Adjust the gap by turning the bolt. Or make the sensor adjustable. Done. Easy.


And in a few weeks we'll have our new all-in-one Twin Trigger ready -- hall-effect crank (reference) and cam (synch) in one assembly, bolt onto any 1976-94 Turbo.

[drmatera]

sweet, that will help when i step up to MS3x next year. MS2 is great, don't get me wrong. It's just a natural progression.

We'll be layin a tune in Frankies beast tonight... hold on Fred

[Ken911]

question: i am guessing that the position of the sensor and bolt are with number 1 cylinder at tdc. on the firing stroke?

[sjf911]

The single tooth cam signal tells the ECU that the next missing tooth on the crank indicates combustion cycle on #1 so it needs to be before the missing tooth. You also have to avoid any overlap with the missing tooth with megasquirt.

[Ken911]

Originally Posted by sjf911

The single tooth cam signal tells the ECU that the next missing tooth on the crank indicates combustion cycle on #1 so it needs to be before the missing tooth. You also have to avoid any overlap with the missing tooth with megasquirt.

I meant the one in the picture above. will that work with the ms-3? so i just pick something like 5 degrees advance and install it there?

[sjf911]

Any single tooth cam signal like above will work with megasquirt. You just want to make sure the signal is before the crank missing tooth. Setting it 5 degrees may not be enough to ensure it doesn't overlap with the missing tooth. My cam signal based on the rising edge of the tooth occurs about 60 crank degrees (30 cam degrees) before the missing tooth.

[Ken911]

ok so i need to put the bolt so that the last part of it is past the sensor by 10 degrees or so? pardon me for sounding dumb. But i'm still trying to figure out exactly what i need to do before spending/wasting any money on this system. Just dont want to buy anything i dont need and want to not spend too much on what i do need.

[sjf911]

LOL, not dumb. It is quite confusing at times especially with the cam rotating at half the speed of the crank and in opposite directions and the missing tooth sensor offset from true TDC. You just want to be sure that the rising or falling edge (preferably both) of your cam sensor signal occurs before the missing tooth signal for TDC of compression (somewhere in the 360 degrees after exhaust TDC and before compression TDC. The missing tooth is usually close to TDC on the crank but the sensor is offset advanced by 60 degrees on the 911 (standard Clewett or GSF sensor bracket). On my setup, the cam tooth rising edge signal is 60 degrees in advance of the missing tooth so a total of 120 crank degrees BTDC compression.

Megasquirt-3 MS3 Trigger Wheel

[Ken911]

Oh so your saying with a cam sensor I still need the crank trigger also? That just doesnt make sense to me that you would need both.