Tuning an 3.4

[Raidenvaga]

Hey guy what are the best way to tune an 3.4 f-body car. I'm looking more for an program that I get to tune it myself... the 3.4 for gets no love for tuning hyper & superchip ( :bs: ) LOL... Really I'm serious, What can I do

[White95]

Re: Tuning an 3.4

megasquirt ($400) or FAST ($4000)

[Raidenvaga]

Re: Tuning an 3.4

Meaning ???

[Raidenvaga]

Re: Tuning an 3.4

I'm sorry , I understand now... Theres is an whole lot of reading to do on that site, lol ... Thank you for your trouble

[TurboProject]

Re: Tuning an 3.4

Hey,

I'm running a megasquirt on my 3.4. I just posted a pretty involved post over at www.fullthrottlev6.com but I'll go ahead and copy it here:

I have a '94 3.4L 5-spd camaro and have been running Megasquirt on it for 2.5 years and it's been working out great. I started out with it controling fuel only but I have since added the capability for it to control the stock GM DIS ignition as well. Between that time I had also adapted a ford DIS system before I figured out how to make the stock DIS work but I have since taken that off.

Now, to give some perspective on price and what it takes to get where I am today, you can either buy a complete unassembled kit and built it yourself if you know how to solder(it's really not that hard with the right iron, etc), or you can buy an already assembled megasquirt.
The kit I am running that has the capability to run fuel and spark(and a bunch of other features such as N2O, cooling fan on/off, etc) will run you $140 unassembled from www.glensgarage.com. It is the V2.2 mainbaord with the MS-I processor (not MS-II). I say it has the capability because after you build it to spec with that kit it comes with the original code flashed into the processor and there are also some minor hardware modifications needed to run the ignition control. These modifications include flashing in new code and soldering in 2 resistors that only cost a few cents and running a couple of jumper wires on the board. I have written up a guide on how to do this for the megasquirt version I'm running.
You can buy a compleatly assembled version of the $140 kit for $240 from www.diyautotune.com.

Now, for the code that has all the extra features, it is free for download and can be flashed in yourself. All you need is a computer with a serial port and a serial cable. The site for that code is here(it's called Megasquirt-n-spark-Extra, or MSnS-Extra): http://megasquirt.sourceforge.net/extra/
Check out all of the features it has.

Now this is pretty much the cheapest route to use the megasquirt to get full fuel and ignition timing control on a 3.4L V6. I did it for slightly less by buying the basic kit directly from www.megasquirt.info which is just the bare mainboard, the processor with code, and a few other key components for $60. I then scrounged up the remaining parts and managed to assemble that same $140 kit for ~$100. You can do this too if you know your way around simple electronic parts and know where to find them for cheap.

Now, from there megasquirt just starts getting more expensive. You can get a MS-II processor and plop it into that V2.2 board but just the MS-II processor alone is $82 from www.glensgarage.com. You can also use the V3.0 mainboard with either the MS-I processor or the MS-II processor. The V3.0 mainboard has extra features that the V2.2 does not have such as a built in VR circuit(for ignition pick-up, etc), the ability to run either high or low impeadence injectors(the V2.2 by itself will only run high impeadance without adding an extra "flyback" board), and a built in single coil driver so if you had a distributor with one coil you could drive it directly without an external ignition module. The MS-II processor has a lot more potential than the MS-I pricessor but right now it doesn't have as many features as listed on that site for the MS-I code I'm running(MSnS-Extra). It does have support for running a stepper motor style IAC valve however. At this time I'm not running any type of idle control. I just set the idle with the idle set screw on my LT1 throttle body high enough so that when the A/C is on the engine won't die. There are options for adding idle air control with a MS-I processor without using the stock GM stepper motor, I just haven't fooled around with it because my setup is working fine for me.

Now, for a breakdown of hardware prices:

MS-I with V2.2 mainboard:
$140 unassembled (glensgarage.com)
$240 assembled (diyautotune.com)

MS-I with V3.0 mainboard:
$189 unassembled (glensgarage.com)
$329 assembled (glensgarage.com)

MS-II with V2.2 mainboard:
No one really carries this combination because it was kind of an intermediate step before the V3.0 board came out, but you could buy a MS-I\V2.2 kit and the MS-II processor for $82 if you really wanted it. So let's say:
$140+$82=$222 unassembled (glensgarage.com)
$240+$82=$322 assembled, you would have to add in the MS-II yourself. If you can install a processor in a PC you could install this one. (glensgarage.com)

MS-II with V3.0 mainboard:
$250 unassembled (glensgarage.com or diyautotune.com)
$400 assembled (glensgarage.com)

ALL subsequent code versions to flash into the processor are free to download and flash in yourself and people are improving on it by adding extra features all the time. The tuning software is also totally free and they have PC, Linux, and even Palm based versions. The only thing you pay for is the inital hardware.

Now let me explain all of what I'm running with my MS-I, V2.2 megasquirt.
I'm controlling fuel and ignition timing. I'm feeding it a wideband O2 signal(an Innovate LC-1) and after you get your fuel table pretty close it will target desired A/F ratios based on another table. So I can have it run closed loop 14.7 when I'm just cruising down the highway and I can also run closed loop 11.5 AFR when going WOT and under heavy boost. The megasquirt also turns my cooling fans on and off at temps I chose. I have played around with knock sensing(w/ ignition retard) but I was getting too many false readings. Actually I haven't devoted all that much time to making it work right. I have also played around with electronic boost control and it worked for a while but I need to get a better solenoid valve that is connected to the wastegate. This kit comes with a MAP sensor that will go up to 22psi boost. You can swap out MAP sensors to get much higher if need be. I have also hooked up a pressure transducer to measure exhaust backpressure and I use the megasquirt(and a laptop) to log it. I did this too see how much backpressure is in the exhaust before the turbo. You could put this pressure transducer anywhere such as to measure fuel pressure, oil pressure, whatever.
And just FYI, I'm not sure if any of those venders will sell you a megasquirt that's ready to just wire right in with all of the options I listed. If they would, they would most likely charge you extra. But the modifications really are minimal for ignition control.
Right now the only thing my stock computer is doing is turning the A/C compressor on/off and controlling my speedometer.

Now for the drawbacks.
Unless you want to devote a bunch of time in playing with custom programs and things it's not going to control emissions hardware such as EVAP solenoids, AIR pumps, and EGR valves. You might be able to trick the stock PCM enough into thinking it's still in control and have it control those things but I've never tried. You might be able to do the same thing to get the stock computer to control a 4L60E transmission. There are some who have tried to control it with a megasquirt but I believe it takes 2 megasquirts...one for the engine and one for the transmission, I think this is something they are working on to get 1 to control both.

Also, as of now megasquirt is batch fire ignition, not sequential. But they are working on it and getting close. It will require using a MS-II processor. Check out this site about it: http://www.megamanual.com/router/
As you see there it might be coming out as early as mid-2007.
Just to give you some perspective, with my setup I'm getting 21-21.5 miles/gallon on my daily work commute in my car. I never got higher than 19 when this car was totally stock. I achieved this through tuning for optimal economy during highway cruise only. I still run retarted ignition and 12-11.5 AFR when under boost and I boost as high as 10psi on my totally internally stock motor.
So stock SFI = 19mpg
MS-I batch = 21.5mpg with economy cruise tuning(2000-3000rpm, and ~10inHg vaccumm)

Also, on this stock motor I have run a time of 14.2 @98.8 mph in my 3550lb race weight camaro with street tires and 10psi boost.

Here is a list of sites for more information:
www.megasquirt.info - the main info site
www.msefi.com - the message board
http://not2fast.wryday.com/megasquirt/mt/2.25/ - the tuning software

Hopefully that gives a pretty good overview of the Megasquirt option for the 3.4L. It is of course not limited to the 3.4L but I just wanted to give the story of a sucessful setup and user. I guess the next step is to write up instructions for what I've done so that anyone willing to can replicate what I have done. I already have the instructions on how to get a MS-I V2.2 like mine to work with the GM DIS. And I'm working on the ones for a MS-II V3.0. Driver_10 will be the 1st guinny pig for that combination.

Let me know if you have any other questions.

[97rs4life]

Re: Tuning an 3.4

nice writeup TurboProject. Some good info

[SpeedingFirebird]

Re: Tuning an 3.4

Great info man! thanks! :tup:

[camaroman1181]

Re: Tuning an 3.4

This post answers a lot of questions that are normally thrown around about tuning the 3.4... rather than TurboProject constantly retyping it, how bout we post this up top as a sticky????? I'm sure all the 3.4 guys would appreciated it (myself included.. i keep losing the printouts of how to do this for my car.. lol)

[TurboProject]

Re: Tuning an 3.4

rather than TurboProject constantly retyping it, how bout we post this up top as a sticky?????

That sounds good to me. :)
Sometimes I just do a search for megasquirt to see who is asking about it. A sticky would make things a little easier...

[black95maro]

Re: Tuning an 3.4

That sounds good to me. :)
Sometimes I just do a search for megasquirt to see who is asking about it. A sticky would make things a little easier...

I say sticky too!!

[speedracer95v6]

Re: Tuning an 3.4

So what do we do if we have a 4l60e? Is there anything we can do other than running two megasquirts?

Does anyone have the base maps, etc. that they can send for flashing in the even I do get one of these (so as to make tuning less of a *****).

[White95]

Re: Tuning an 3.4

i'm using a TCI tranny controler

[The_Beast]

Re: Tuning an 3.4

Is this all I need, or do I need to buy anything else? Thanks.

http://www.glensgarage.com/catalog/m...-v22-p-29.html

[speedracer95v6]

Re: Tuning an 3.4

i'm using a TCI tranny controler

Ouch! Nice, but not cheap!..lol.

[The_Beast]

Re: Tuning an 3.4

OK I have another question. Can I expect to see any gains just from the program, or do I need major mods to see any? I plan on doing the head swap pretty soon, but I just wanted to know if it'll do anything while I'm still mostly stock.