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-   -   Is anyone using megasquirt standalone? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/anyone-using-megasquirt-standalone-296358/)

GtoRx7 04-18-04 11:40 PM

Is anyone using megasquirt standalone?
 
I've been hearing some things about this system(mega squirt), it is fully programmable, and some people say its as good as haltech and microtech, just way cheaper. I wanna know if anyone is running it, and know its proven. Any replys at all will help me alot! Thanks

razorback 04-19-04 12:16 AM

i am interested in this as well. please post info on it. and experiences.

AcidShock 04-19-04 12:21 AM

A link to the homepage. Really nifty stuff and there is a big support forum for it too.

http://www.bgsoflex.com/megasquirt.html

pip 04-19-04 12:30 AM

I remember reading about this maybe 3.5 years ago and I still dont know anyone who has one =(

slomo85 04-20-04 07:02 PM

wow, that thing is cool. I'll be using that, screw the haltech prices, heh. I hope they come out with the ignition controlling unit soon though. Can I add that function on to the existing one if I were to build it soon? Ohh well, I can wait...later:)

razorback 04-20-04 07:08 PM

i think im going to try this..

razorback 04-20-04 07:20 PM

i read this on the forum there.

Hi Ian, I had the MS running on my turbo FC for quite a while and am
currently working with a friend to install one on his NA FC. Just a few
notes: for my install I kept the stock ecu (so that it will still retard
timing under boost) but with my buddies NA car we are going to install a FB
12a distributor to handle spark so that we can remove the stock ecu
completely. Both of us are using the Dual Table code and have no problems
firing in batch versus the stock sequential. As for sensors I'm using
seperate sensors for the MS and ECU, but on the NA there will be only one
set of sensors for the MS only.
That's all a little vague, but the bottom line is that it can be done, it
works really well, and there is a ton of info here. I'm sure one of the NA
guys (like Roger or Mike) will chime in soon. All the help I needed, I got
here....these guys are really great.
-John
www.TwistedRotors.com


Yes, it will fit right in. There is a mark on the gear, I think it's
different than the one on the CAS, my memory is failing me. I'll compare
the two later tomorrow when I get home, I've got one of each on the
shelf. The 12A distributed igntion uses 2 coils, one leading, one
trailing. It fires the leadings simultaneously and alternatese the
trailing firing as appropriate. It has "igniters" on the distributor
which process the reluctor input into current feed to the coils. There
was a 13B version of this distributor cap model, there was only a very
slight difference in the advance curves - 12.5 v 13.75 degrees
centrifugal, all in by roughly 2000 rpm. The vac advance was slightly
different as well but I recall it almost being small enough to be within
mfg tolerances. That said, I've seen a couple of the 12A ignitions on
13Bs, the owners said they ran great. I personally know of one locally
who I see every couple of months and he's been running that for at least
3 years and never mentions it so I'm thinking he's happy with it. Just
got to get him away from those nasty carbs! You cannot use the coils you
have now - those definitely need the ECU's voodoo to trigger correctly
-and- you'll burn up the very expensive 12A igniters very soon.

-Mike


and what is the cost to build this?? how hard is it?

patman 04-20-04 07:44 PM

i just heard about this too...im totally interested in slapping one in my TII.

Question 1: what all does the ecu control on our cars? like, will my guages still work?

Question 2: can i use the megasquirt EDIS ignition add-on and keep my 13B ignition setup?

Question 3: Will it run primary and secondary injectors seperately?

pat

patman 04-20-04 07:46 PM

also, will the stock ecu still work as far as ignition goes with all the fuel stuff unhooked?

renns 04-20-04 09:24 PM

Razorback contacted me about the MS system, so I thought I may as well respond here...

Here's the deal on the Megasquirt (hereafter referred to as 'MS'), questions answered in random order:

It is a standalone programmable fuel injection controller. There have been some variations developed that also provide programmable ignition control, but only for distributor-based or Ford EDIS ignition systems. There are many people using these systems to control both fuel and spark on piston engine applications, but there is no one that I know of doing the same on a rotary due to timing split issues.

The MS is usually purchased in kit form for less than $200, although there are some enterprising folks now selling pre-built units on Ebay. My personal feeling is that if you are not up to soldering the thing together, you probably should be looking elsewhere, but many disagree with me on this point.

The project is completely open source, with all program code available at no cost. Tuning software for Windows, WinCE, Palm, and Linux have been developed by MS group members, and is available at no charge (including source code in most cases). This makes the system well-suited to those that want to (and have the ability to) customize the controller for their purposes.

There are dozens of modifications that users have developed and presented to the group. Some modifications that come to mind are: 1.) rpm, map, or coolant temperature-based outputs for shift light, electric fan, water injection, NOS control etc, 2.) Multi-step rev limiter for launch control, 3.) Idle air control valve output (pwm) for closed-loop idle speed control, 4.) Electronic boost control...

The MS can be configured to work with the stock FC ecu still controlling spark, or as an auxilliary injector controller only, or with a 1st gen dizzy to get rid of the stock ECU entirely. I am using option 1 with my FC, and option 3 with my SA.

I have not tuned any other programmable efi systems, so I can't provide any useful comparative data in this regard. The tuning software is very well-done, making the task of getting the car driving well pretty easy. There are also tuning tools available, which use the O2 sensor signal to create an updated VE table while you drive. This can be used with a narrow-band sensor to create a table at 14.7:1 afr, and then manually adjusted to get the desired afr, or with a wideband O2 sensor to tune to a specific afr immediately. Tuning is complicated by the injector staging scheme; see below.

The MS system has two injector outputs, which can be configured to fire together (batch), alternating (ping-pong), or independently. If set up independently, it is possible to control primaries and secondaries in a rotary application separately regardless of size, with the transition being based on rpm, map or a combination of the two.

Advantages: Open source (it is possible to change the program operation to suit your needs), high-quality highly technical discussion group for quick answers to questions, documentation that is second to none (Lance does a fabulous job, see link), low cost.
link: http://www.megasquirt.info/manual/mtabcon.htm

Disadvantages: Not well known (your local tuner may not be familiar with or interested in learning a new system), supplied as a kit you need to assemble, no rotary ignition control, no 'installation kit' to easily adapt to your vehicle. Staged injection is not as straightforward as it could be to tune, as you need to tune primaries and secondaries separately. It would be much simpler if a transition duty cycle (or pulse width) could be specified, and then simply tune via one map.

In summary: If you are interested in electronics, and have a decent understanding of efi, automotive wiring, and efi tuning (or want to learn), then the MS system is a good choice. If you want to buy something you can simply bolt in and go, this is not for you for the reasons mentioned above. If you are between those two extremes, take some time to read portions of the MegaManual in the link above, and make your decision from there.

pip 04-20-04 09:50 PM

Awesome info man, ive been waiting forever for someone to answer everyone of those questions you just answered. Now its time for one more, are you running a wide band or narrow band o2 sensor with your ms?

razorback 04-20-04 09:58 PM

thanks. that answered ALOT of questions. so wanna build a ms for me in a month or so? :D

and this may sound like a stupid questions but how does the wiring harness thing work? (do you use the stock one?)

renns 04-20-04 10:00 PM

I've used both, WB and controller from http://www.diy-wb.com for tuning purposes, and the stock NB for everyday use.

eyeoutthere 04-20-04 10:10 PM

WOW! Good info guys!

Mx6-Rx7 Addict 04-20-04 10:14 PM

Yes... Twisted Rotors, and myself have installed the megasquirt standalone on his TII (he did most of the work). We were running his car tuned on the primaries for a little while, and then we were also using a DIY Wideband as well. Something went wrong and we blew his engine tuning the secondaries.. We are pretty sure it has to do with the wide band. So we are going to swap the megasquirt over to my ported N/A. We will be buying a reputable wideband system. I will be removing most of the engine harness except for the necessary things and controll most with the megasquirt. I also plan to go with IDA individual throttle bodies for the ultimate N/A. I can say that the megasquirt is definately the biggest bang for the buck as far as a fuel controller.... but thats exactly what it only is.. a fuel controller... it doesn't control ignition. There are ways you can control ignition with it such as megajolt, but its simply nothing like a top end model haltech or microtech.

I wouldn't suggest using the megasquirt if you don't know much about electronics. Make sure you can solder too.. Although, ive seen fully built units on ebay for a decent price.

Anyway, thats my opinion....
Good luck
Justin

renns 04-20-04 10:17 PM


Originally posted by razorback
thanks. that answered ALOT of questions. so wanna build a ms for me in a month or so? :D
No thanks. But there are a number of people on the MS list that offer that service. More than one sells on Ebay.


and this may sound like a stupid questions but how does the wiring harness thing work? (do you use the stock one?)
You can either hack the harness, or sacrifice an ecu by cutting and making connections to the connector inside the ecu itself. I chose to sacrifice the stock ecu, as I had a spare and wanted to be able to throw another unmodified ecu in if needed.

DCRotor 04-20-04 10:32 PM

Well sounds like a great project to me. Thanks for the info i'll be doing this DIY ems over the summer alone with my first 1/2 bridge port N/A. so much to do so little time. :-D

pinkfloyd 04-20-04 11:46 PM

i thought you can controle everything with the new chip, i think its called super ms, or something. Why do you say its not like the top of line sytem like haltec. If you know what your doing you can do everything a haltec can.

Spooledup300z 04-20-04 11:59 PM

Im using it, and so far so good, just got the car started, gonna start tuning soon

rotoboy20 04-21-04 12:13 AM

cheep...yes

i have to build it my self? WTF? or are they talking about the maps?

nonameo 04-21-04 12:17 AM


Originally posted by rotoboy20
cheep...yes

i have to build it my self? WTF? or are they talking about the maps?

yep, you do all of the soldering and building yourself.

Mx6-Rx7 Addict 04-21-04 12:58 AM


Originally posted by pinkfloyd
i thought you can controle everything with the new chip, i think its called super ms, or something. Why do you say its not like the top of line sytem like haltec. If you know what your doing you can do everything a haltec can.

Ah yes... it's called the Ultra-Megasquirt.. and as far as i know it's not released yet. This stand-alone is from what i understand a very good system... i'm sure there are updates on the website about it.

This system is very different from what the ultra megasquirt is.. thats why i say the megasquirt is no haltech etc...




Justin

pinkfloyd 04-21-04 01:01 AM

ok, sweet, i will look into the ultra ms when it comes out, and when im smarter, lol. I dont now how you guys do it, its so confusing. My friend just had one made for his volvo.

Kenteth 04-21-04 01:06 AM


Originally posted by nonameo
yep, you do all of the soldering and building yourself.
Solderign on PCB is pretty easy. If you've ever used a soldering iron, you could pretty easily be able to solder a PCB. Soldering micro pcb though is different, and somethign i personaly refuse to try :P I'll leave that for the robots at dell

SonicRaT 04-21-04 01:17 AM

I've built it, installed it, watched it run, did it for friends, and bought the t-shirt. Lemme read through all the questions and see what I can answer.


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