MidwestTurboII

I searched but all the results were listed in the first gen forum so that did me no good. I have an 87 TII, essentially stock. Im starting to mod the car and i see kits for the megasquirt for like 300$ or so. Seems cheaper than some of the other management systems. My questions are; how easy is this to install and get running on your car, does it work for TII or only n/a, and lastly will it remove any functions i need/like on the car. oh, its a v2.2 and yes i have a laptop if i need one to use it with.

MARTIN

I heard that the megasquirt can only do the fuel maps. And you would either need to keep your ecu or use a dizzy. Its cheaper but its a bit more complicated in gettin it tuned as far as I can tell from the software. If I were you I would get another ecu with more support from the people that are actually using.

(Edit for sig violation...CHECK YOUR PMs)

BIO3M

Megasquirt is good stuff. Ive done some custom turbo kits in my day and the megasquirt was one of the better FMU options. Ive toyed with Apexi SAFC's and so on but they arent nearly as good as a megasquirt. Basicly all it does is monitor the 02 sensor...if it reads to rich it cuts fuel a bit if its too lean it increases fuel....very simply but very effective. With SAFCs there is major guess work...

Tofuball

MegaSquirt controls my fuel and my ignition.

Do not buy it unless you are willing to learn about it, and programming it for yourself.

It's a DIY ECU. Biuld it yourself. If you have to buy one of those premade kits, Megasquirt is not for you. :O

Tofuball

I'm using it on my car to control my stock ignition. Before I was using it to control an HEI module on my stock leading coil. It's not complicated tuning this thing at all. But I agree with you, he should get an ECU with more support.


No, the S-AFC does not monitor the O2 sensor. . . If you are reffering to the megasquirt, you're wrong, it's a true aftermarket ECU, a replacement for the stock ECU, it doesnt "just monitor the O2 sensor" and add or subtract fuel.

S-AFC and MegaSquirt, its not guess work, you can use a Wideband (And/Or a Dyno) with either one.

MidwestTurboII

ok well as much as i wish i had time to learn how to program the ecu etc, i only have one car, so i need something that can be installed and running driveable in like a few days. Im pretty good with wiring, and im solid with laptops (and i can read install instructions lol). but i havent ever done anything like this before. I think it would be a cool thing for my car. Since megasquirt seems a bit complicated for me to use, what other system could i use? AEM EMS is like 1300 bux, and greddy emangage is expensive too. Ive heard good things about the Haltech E6K but used there still 900 or so.,

MARTIN

Well I am in the market for an ecu too, basically your choices are either microtech and haltech, if you are looking for some support. OUt of the bunch of ecus that are widely used, the microtech is the cheapest out there, in terms of the lt8-lt10s vs any other. These retail new for less than $1000. You are looking at about 600-800 for a used one with sensors. The thing is that you need to get it programed for your application if it was not meant to be on a rotary.

ShadowX

First you have to decide what your plans for the car are. If you want to make some serious power and pretty much forgo any emissions legality (and spend $$$), than start looking at Microtech or Haltech. If you just want to make some decent reliable power without spending an arm and a leg than either an S-AFC or E-Manage would probably work.

I got my e-manage with pressure/ignition/injection harnesses for a little under $400 on E-Bay. Nice thing about the E-Manage is that it still uses the stock ECU, meaning that you can install it and the car will start. (As long as you wired it correctly )

In the end, you have to evaluate you budget and decide from there. If you need a full independant fuel system, then you are likely spending a bunch of money on mods already, so your budget should be fairly open-ended in the first place. What I'm really saying is, be realistic about the performance goals of your car and your ability to reach that with your budget.

edmcguirk

The MegaSquirt by itself does not do ignition but there are a few Rx7 guys on the MegaSquirt forum who are getting real close to solving the rotary ignition from the stock CAS. They have figured out how to read the CAS, they can do leading ignition and they are very close to getting the trailing ignition.(last time I looked)

Or just use a distributer from a 12A.

There is actually very good support on the forum www.msefi.com (A lot of people think the support is better than most high dollar systems)

But it is DIY. You should be able to splice it in place of the stock ECU and use all the stock sensors. You would need to fabricate a throttle position sensor.

Then you can start tuning...

Anyway, tuning any fuel injection computer is going to be difficult (I would say impossible without dyno time or at least a wideband).

ed

muythaibxr

I'm one of the people doing the leading ignition (I think I'm the first to have it working with a stock CAS with megasquirt, and I think some people are holding off until I have something working perfect, namely the values of the pull-up resistors) Trailing will be coming pretty soon (maybe in less than a month?) We're doing this work on Tofuball's car.

Making it control ignition and read a CAS requires 1) a firmware upgrade 2) build a dual lm1815 circuit (I have schematics) 3) some mods to the megasquirt hardware (adding pull-up resistors, the exact value of resistor to add is something I'm still experimenting with, 1K is too low, 2.2 is too high so there are misses on idle occasionally but above idle works well... tomorrow I'm going to try with a 1.5K resistor; you also have to add a couple of jumper wires, but none of it is very difficult)

agreed, people are very helpful there, and I don't think I've ever seen anyone act stupid there...

Wrong, Megasquirt works fine with the stock TPS assuming it's working right... we're using it on tofuball's car. Other than that you're correct, you have to splice it into the factory harness or create a new harness.

We are using a wideband to tune fuel, and once we get stock trailing working, will use dual EGT's to help tune ignition. We think we can do significantly better than stock with this setup power and economy wise. We will eventually dyno the car, but I'm not sure when.

The point is that there are people who have gotten tunes they are perfectly happy with and they didn't even use wideband or dyno tune... they just used the butt dyno, and made sure they were reading rich when at high load. I agree the dyno is the best way to go if you want the most power possible.

Anyway, my advice is that if you want to save a lot of money, and do some DIY circuit building (you'll get good at soldering really quick) and wiring... megasquirt is the way to go, otherwise stick with something that's more or less plug 'n play.

edmcguirk

Since the TPS on my 87 only touches the throttle in the first part of the throttle's movement, I assumed it would not work well. Even though a TPS is easy to fabricate, it's good to know I don't have to.

I also know that I could use the sudden change in MAP instead of a TPS for acceleration enrichment.

ed

muythaibxr

yeah, some people like MAPdot accel, but I've found that TPSdot works fine for me... You should have 2 TPS's if I'm correct, one of them is kinda like an on-off switch, the other is always in contact. That's how Tofuball's NA s5 is set up.

MARTIN

Actually the microtech comes with a base map to get you up and running, very close to the stock map. It uses factory sensors, except the afm. And its very well priced. You can pick one up for less than a used e6k even and f10.

The emanage, well, you said it yourself, its a piggy back, which still uses the stock ecu. Which on a turbo car, means you keep one of the most restrictive thing, the afm. Although the emanage is a very good piggy back system and for the price its unbeatable. Definitely better than a safc. But basically, its up to your budget and goals. If its your daily driver then I suggest you either buy an safc or emanage and stick with mild upgrades..

WonkoTheSane

iTrader: (2)

I just got the megasquirt running in my car this past weekend. Honestly, I would not recommend putting in ANY aftermarket ECU if you're going to be limited for time. This is not a job you want to rush because you have to have the car running properly on monday. I can't see how any aftermarket would be any easier. Even if you spent less time on the wiring, you'd still be trying to tune it, which takes quite a while to learn what everything means..

The nice thing about the MegaSquirt is that it has an optional simulator board, where you can make sure everything tests out okay, and learn how changes affect things before you install it, but there's no experience like real experience.

The support is awesome with MS, and the stimulator board is a really nice learning tool, but I still can't see how any aftermarket ECU would be to get set up for a complete n00b in one weekend. I know there's no way I could have done it (this only applies to those of us who have never installed/used a programmable ECU/Fuel controller). I'd be even more wary of using it on a boosted application. If I over-lean, I backfire. If you overlean, you detonate.

Maybe SAFC II is a better choice?

Tofuball

He has an S4 (87) Therefore he doesnt have the extra wide-range TPS (Used on the S5 to control the OMP), he only has a single narrow range.

Node

iTrader: (1)

rotarygod runs a megasquirt, may want to ask him

also there is a megasquirt message board on groups.yahoo.com

muythaibxr

I'm not sure how many people still post there, the main megasquirt forum is:

megasquirt forum

CrazyDude

OK, so this is something I have been wondering about for a little while now: running a megasquirt and stock ECU together, with the stock ECU doing ignition.

So the MS needs coolant temp, air temp, MAP, TPS, and RPM, yes?
So coolant and air temp can be read from the stock sensors by modifying the circuit that reads their resistance, and I think you just assume that the stock ECU uses the same reference voltage

And now some folks here say saying that I can use the full-range part of my S5 TPS to give the MS a signal. Sweet.

RPM should be easy (just 1 wire from one of the coils, right?)

So then, with that in place, should you just be able to cut the wires going from the stock ECU to the injectors, and then run them with the MS?
I am guessing that even if that setup would work, I still can't ditch my AFM, as it affects 6port, vdi, timing, etc? yes?

Someone smarter than me should validate this plan!

edmcguirk

Yes, it's a little tricky but you can tap into the sensors that are still feeding the stock ECU and run just the injectors while the ECU controls everything else. However GM sensors are cheap enough to just add in extra sensors. Temperature sensors and TPS can be added or carefully biased to split their signals between both, Oxygen sensor can be spliced between both without any tricks, RPM can be taken off the spark or possibly the ignitor trigger, tach, or CAS signal.

You will lose the stock rev limiter and I don't know what would happen to the ignition if you go too far past the stock rev limit but you can program MegaSquirt to limit at about the same RPM.

And then swap out the other controls as you figure them out. If you like.

ed

CrazyDude

well, I wanted to try and make an minimally invasive install as possible... I got some samples of the connectors on the mazda ECU, and I hope to make up a simple PCB that'll pass through most of the pins, but allow breakout of the the important ones (maybe 10 or so).
The idea being that I can plug my wiring harness into it, it into my stock ECU, and use that to get all the sensor signals and such into my MS, tap power from a fuse, and then the only thing I'll need to route from the engine bay through my firewall is the teeniest little vacuum tube I can find!

Yes, I realize that a bit involved, considering I am trying to use the MS piggybacked for an S5 NA->turbo conversion, but I just really don't want to start cutting up parts of my car....
I'd really like to get rid of the AFM, and should buy a Haltech, but then the car will >never< be "right" again....

And I was going to use a Crane Cams MSD box w/ rev limiter and boost retard to help with the ignition once I add the turbo, BUT now that I think about it, that'll only retard the leading plugs won'it it? and the trailing's will probably start firing way too early.
Maybe this would be easier if I just made up my mind to butcher this car or not....

Tofuball

Sounds like too much trouble to me. Scrap your stock engine wiring harness and sensors. Do it right the first time

CrazyDude

Can't do that until I raise the $1000 to buy a haltech I don't understand how to do ignition on the MS at all!

Any chance you could give instructions on how to go about using the full range part of the S5 TPS with the MS? here or via PM.... please?

Also, for the injector hookups out of the stock ECU, should I just leave them hanging? or do they needs to be run into a resistor or to ground somewhere?

Tofuball

Its not that complex, you just plug in the TPS the the TPS input on the megasquirt and calibrate it. Use TPSdot

I'm using the stock injector wiring and everything.

WonkoTheSane

iTrader: (2)

short version: Right now ignition doesn't fully work with the MS unit, and the stock CAS and coils.

Long version: There are quite a few people (some on this forum), that are hacking at it to try to get the MS to deal with the stock systems, and it sounds like its close to be solved.

Longer: They're coming out with the Megasquirt Revision II (MS2), that will allow stock timing equipment to be used. The first production batch has been released. The next batch won't go out until the end of july-ish.

You could always do what I'm doing: Use a distributor from a 12a to control your ignition. Not as cool as having control over it, but it will free you from the burden of having to rely ont he stock ECU and wiring to get it up and running, and you can rid of your AFM

I plan on switching back to tstock equipment as soon as the code is stabilized.. I dont' have the time right now to play with it, or else i'd try to figure out how to do it...

Tofuball

Hey, It runs leading fine, trailing isnt exactly nessisary you know :p

The code is being developed still for trailing . . .