Something w/ rabbits. 72.5 pages of BS

[John_Rock]

 

[Burns]

Im interested to see the MegaSquirt come together. Some of my gear head friends have talked about a system like this and I have been interested in it since.

 

[IZwack]

Stimulator assembled

Havent done continuity test cauz multimeter is in the garage - will doooooooooooo that tomorrow.

 

[Turdle]

I'm already stimulated. It works fine

 

[IZwack]

Megasquirt II is capable of controlling fuel and spark on many different systems. Mine for example is contolling a late 80's GM small cap HEI. The computer controls advance, dwell, etc. It is also capable as IZ stated of driving the Ford EDIS system, as well as many others.

It is definitely not plug and play. I like it for the flexibility it gives me, plus the cost is pretty low. For those interested, there is ALOT of information at The Megamanual, as well as at DIY Auto Tune.

Alright seafarer76, next question :

What did you do for the 'idle air'?

I'm reading (from this thread) that the stock PWM-based Ford IAC will do just fine with MS2. Or do you think the almost infinite control of the GM stepper motor IAC is worth converting to?

My only motivation to the GM IAC is that the developers seem to sway more towards the GM side so off the bat, GM sensors/actuators get more support than Ford. So in the long run, GM parts would be easier to work with.

The options:
Stock Ford IAC:

or the GM unit:

----------------

As for tonight, I did a few continuity tests on the Stimulator and everything went okay so I moved on to the main board:

 

[seafarer76]

I like the GM IAC. They supposedly are working on closed loop idle speed control. Right now the Idle air portion of the code only opens the IAC when the engine is cold, then slowly closes the valve as the engine warms.

When they implement the closed loop idle speed control in the code, then the GM IAC may be the better option in my opinion.

DIY Autotune has a block that the GM IAC bolts into if you don't want to modify your manifold.

 

[410Fortune]

GM IAC = POS
I hate those things, I have replaced 3-4 of them in the TBI 350 setups and none of those were even my truck! the ford units get cleaned and re-installed plus they are METAL!!!


Ford IAC = works good in comparison! LOL of course by the time the TBI or EFI 350 comes to my house its because the owner is broke and out of idea's! LOL @ friends

 

[seafarer76]

MY GM IAC is metal as well. There are a few different designs, some bolt on, some screw in.

 

[james t]

Ive owned quite a few GM TBI's over the years... never had an IAC fail (knock on wood). Been through a million ignition control modules though. :

 

[IZwack]

Soo is this the general operation of the GM IAC? I ask becuase I've never personally seen one and I'm probably going to throw together an aluminum adapter doodad for the stock IAC port on the plenum.

 

[JTX]

Something w/ rabbits an Nerd Talk. 80 pages of BS

 

[IZwack]

Something w/ rabbits an Nerd Talk. 80 pages of BS

Something w/ rabbits and Nerd **** :

Annnnnyways, stupid me doesn't have a DB9 serial cable with male/female ends so I had to plug the board directly to the back of my laptop. But I was able to load a firmware onto the MegaSquirt's controller and MegaSquirt's on-board clock registered on the laptop.

 

[section525]

What?

 

[jwrezz]

Ya know, I had that MAF tuner a couple years ago, and it had the 9pin serial cable and I was so disgusted because even then every computer was DONE w/ them and had made the switch to USB. The auto aftermarket is SO FAR BEHIND in their use of even years old technology. Like all those guys that swear OBD and computer controlled engines are just "so impossible to work on". Seems like the industry really needs an influx of some real tech geeks. Especially so us Linux/Mac users can actually get some software coded for our machines!

 

[jwrezz]

Oh, and mine is only 25 pages of BS. I hate having to click to the next page, so I set that up in my "User CP"

 

[410Fortune]

thats awesome IZ, megasquirt! build me one build me one!! LOL

ignition control modules

Thats the problem with the TBI when it runs like crap you start replacing parts, and of course we all know its always the last part you replace! LOL
I have re seated those stupid injectors, new FPR, new TPS, new IAC, blah blah blah still runs like crap...hahaha they are strong motors when they run though! I have a 99 GMC 2500, took 6 months to get it running right, now its been a year since I had to touch it (I dont drive it, its on loan to brother in law LOL his Hemi 5.7L sucked a valve at 70K miles, still making payments, saving for a $5000 engine)

Truck looks amazing I love the rear shock hanger bulk head thingy jobbertrac bar hanger creation, purley awesome, you can finally see it really coming together and still retaining some sort of explorer looking body! Nice work thus far!! Serious inspiration on this forum for my upcoming BII body diet cage project

 

[seafarer76]

Soo is this the general operation of the GM IAC? I ask becuase I've never personally seen one and I'm probably going to throw together an aluminum adapter doodad for the stock IAC port on the plenum.

Yea, that's the basic operation. The passages differ in design by EFI type, but that's how the pintle controls the airflow.

 

[IZwack]

Thanks seafarer76!

Ya know, I had that MAF tuner a couple years ago, and it had the 9pin serial cable and I was so disgusted because even then every computer was DONE w/ them and had made the switch to USB. The auto aftermarket is SO FAR BEHIND in their use of even years old technology. Like all those guys that swear OBD and computer controlled engines are just "so impossible to work on". Seems like the industry really needs an influx of some real tech geeks. Especially so us Linux/Mac users can actually get some software coded for our machines!

DB9 is still a standard in the PC world but I think its gone in the Mac world. I dont think the PC world (at least the desktop) can get away from DB9 cauz its a standard in pretty much every form factor. And there's realy nothing wrong with RS232 for something like this considering the baud rate of MegaSquirt, but I guess USB has been the standard for quite some time now. But I dont think it would take a lot of effort to migrate MegaSquirt to native USB (remove the MAX232 IC and plop in a USB equivalent IC, probably in the prototyping area of the board and reroute the traces with some jumpers). The firmware has to be updated too I guess because as I remember, USB has device 'classes' that identifies what type of device you're trying to hook up. So I guess USB takes a bit more work where as RS232 is just a flat out connection, no handshaking, sync, identification or anything.

Having said all that however, there are DB9-to-USB adapters that will allow you to configure MegaSquirt through the USB. And Megatinux (http://megatunix.sourceforge.net) is an equivalent of the Windows-based MegaTune but obviously for Linux. I will probably be running a flavor of Linux for the on-board computer and display so Megatinux is what I'll be using once all the hardware is set in stone.

 

[seafarer76]

DIY Aututune USB

This is an adapter that ties into the MS board for USB rather than serial usage. It replaces the MAX232 chip and so it doesn't deal with the level shifting required for RS232 comms.

I have this and have tried it out. It does work, but I haven't installed it. I have been using a typical USB-Serial adapter for tuning as my laptop does not have a serial port.

 

[IZwack]

Woot thanks -- well that page pretty much sums it up!