Megasquirt: 3.4 Guys

[whiteThunder]

I am trying to tune my 3.4 with major mods, and am finding not too much out there. I want to S/C it this winter, but without ample tuning it might be a waste. Does anyone truly understand the Megasquirt out there, and if so would you willing to explain how detailed and in depth it is? Also, it it just for turbo'd applications or what?

[Nikos95]

Re: Megasquirt: 3.4 Guys

I am trying to tune my 3.4 with major mods, and am finding not too much out there. I want to S/C it this winter, but without ample tuning it might be a waste. Does anyone truly understand the Megasquirt out there, and if so would you willing to explain how detailed and in depth it is? Also, it it just for turbo'd applications or what?

I don't understand it or the programming of it at all yet. But it is just a seperate fuel management system, so you could even run it with a stock motor, and just allow more tuning.

[camaroman1181]

Re: Megasquirt: 3.4 Guys

yes.. that is correct. you can run the system with any mods, or even a completely stock engine. if you start doing more advanced things, like FI, nitrous, bigger cams, AL head and intake swaps, that sorta thing, then megasquirt is pretty much the only way to go to help make it all run right.

there is a guy on this site that was the first that im aware of to run megasquirt in his 3.4. Turbo project i think was his name? its something like that... its just escaping me right now. If im not mistaken, he actually was the one that figured out how to wire up the system for our cars and the GM 3 coil pack DIS. If he cant help, megasquirt also has its own forum for people who arent sure on the tuning, or any other problem that might be experienced with implimenting their system. Im going to go this way too when i finally get enough money to start building. its a very nice system and im glad that i didnt have to pay 2k for something like a FAST system.

[TurboProject]

Re: Megasquirt: 3.4 Guys

Hey Guys,

I just saw this post.

Yes, I'm running a megasquirt and am very pleased with the results.

I'm running a turbo and bigger injectors so I needed the megasquirt to tune. I was just running a bigger fuel pump and a FMU with the bigger injectors but it ran pretty rough, especially when cold or at idle. With the megasquirt I was able to tune it to be very smooth.

Basically it took the place of the stock PCM in controlling the engine. It's controlling fuel injectors, ignition timing, radiator fan, fuel pump relay, and of course it's reading all the stock sensors(TPS, coolant temp, air temp, built in MAP sensor - not stock one(good for ~22psi boost), knock sensing is possible).
I'm also running an Innovate LC-1 wideband O2 sensor. This helped a ton with tuning. If you don't use a wideband you really have no idea where you really are with the fuel.

I just recently got better milage than when the car was completly stock. Stock I would get about 19mpg in city/highway mixed. I got the megasquirt to match that and then I pushed it to 20.2mpg by adding a lot more ignition advance. This is with the turbo too, city/highway mixed. So by creative tuning I was able to get better mileage with the megasquirt which is a batch fire system over the stock computer which is a sequential fire system.

I still have my stock PCM in place but the only thing it is controlling is the speedometer and the A/C compressor.

Also, the best I've run with this car is a 14.27 @ 98.8. That was before I had it tuned as well as I do now. It has a lot more advance than it did then and fuel is dialed in much better. This is also on a completly internally stock 3.4. The only thing I've really ever done to the engine was add a LT1 throttle body. Everything else is external(turbo, fuel injectors, etc). Also this engine has 225,000 miles and I've never had the valve covers or lower intake manifold off.

I'm running 36 #/hr injectors @ 45psi fuel pressure with a 255 lph pump in tank.

The megasquirt will pretty much let you tune for any mod you've done to your car. I'm building up an engine for this car that will complement the turbo better and I'll pretty much have to completely re-tune the car. With a different cam it would be a lot different especially in the upper rpms. I have to back way off on the fuel in the upper rpms to maintain a constant air/fuel ratio because the stock engine just can't breath at all up top.

Oh, and as far as costs, I bought my 1st unassembled kit for $140 from www.glensgarage.com
It's the "MS-I" v2.2 board/hardware.
I soldered it all together and did a couple of mods to it that didn't cost really anything(a couple of resistors and stuff) and I had a computer that would control fuel and spark. All of the software for it is free and there are guys constantly modifying it to add new features.

If you have any other questions just let me know. I've been running megasquirt for over 2 years so I've had a lot of time to learn about it.

Other megasquirt sites:
www.megasquirt.info -> the main site with tons of info
www.msefi.com -> the message board with lots of helpful people

[Nikos95]

Re: Megasquirt: 3.4 Guys

Heh not even my thread and tons of info i can use for sure! Thank you very much!

[micyek]

Re: Megasquirt: 3.4 Guys

Hey Guys,

I just saw this post.

Yes, I'm running a megasquirt and am very pleased with the results.

I'm running a turbo and bigger injectors so I needed the megasquirt to tune. I was just running a bigger fuel pump and a FMU with the bigger injectors but it ran pretty rough, especially when cold or at idle. With the megasquirt I was able to tune it to be very smooth.

Do you think I could get a copy of your ".msq" file?

kleslie@altoprecision.com

I would really apreciate it. I was thinking of megasquirting my DSM...but I think my f-body would benifit more.