FB II

this is going on my turbo 12a setup. currently i'm running a stock nikki boost prepped carb and it's bad ***. the fuggin thing is very fast but i think i'm almost maxed out for the turbo setup i'm trying to go with here soon. this goes on the RB holley intake manifold and comes with a harness already setup for megasuirt. it utilizes 4 top feed bosch injectors and of course i want to stage them like a TII's injection setup. what i want to know is... should i go with the v2.2 or v3.0 or what. i'm using fuel only. my locked dizzy works beautifully for my ignition as of now.. even up to 20psi ohhh yes. thanks in advance guys!


edit:: i almost forgot, it has a ford tps.

Rex4Life

Hey that looks like a nice setup.

Very few FI options for a 12a, that's the way to go.

Scott

FB II

thanks REX; if you don't mind... which ms unit are you using? my problem now is do i really need to go with the v3 board? or will the msII work just fine for my fuel setup. you know with the staging of the injectors and all that. i'm still researching alot on this, as i'm a big carb guy and this ms stuff is greek.

muythaibxr

I think you're confused a bit (no offense). When I get around to writing up an FAQ, I'll definitely include this info:

There are several megasquirt options available right now:

Megasquirt v2.2 board with megasquirt 1 chip
Megasquirt v2.2 board with megasquirt 2 daughtercard
Megasquirt v3 board with megasquirt 1 chip
Megasquirt v3 board with megasquirt 2 daughtercard.

The megasquirt 1 chip is what most rotary users will want right now as once upgrade to the msns-extra firmware, it supports rotary ignition, staged injection, and all the other little goodies people want for rotary engines (except maybe S5 OMP control).

the megasquirt 2 daughtercard has a faster chip, with a stepper motor controller, and CAN bus capability... but at this moment, the code for it is pretty limited. I plan on (sometime soon probably) porting over a lot of features from msns-extra to the MS2, but it could be a while before there's something usable, so most people would be better off getting the ms1 chip now, and then upgrading later if needed.

Ken

jayroc

That's exactly the TB I wanted to get for mine. (after I bought the setup I have now, of course..) Let me know how well it works.
I'd use the MS1 v2.2 board with the MSnS-E firmware upgrade. It seems to be getting a lot of development attention these days, especially on the rotary side, and it works quite well.

muythaibxr

The v3 board with the ms1 chip and msns-extra chip should work fine too... and could be done with no extra connectors or boards... just an extra circuit in the proto area.

It just hasn't been done yet that's all. I'm going to be buying another msv3 kit with an ms1 chip to test out that configuration soon.

I'm going to be trying an EFI conversion on a 12a soon, so this info about the throttlebody and such is useful for me too I guess I'll have some research to do in the 1st gen forum when I'm ready for that.

FB II

nice, thank you muythai! i'm lookin in to getting something pretty soon 'cause i want this setup before winter gotta let the turbo setup take advantage of the cold weather hahaha. so i guess i'll just go with the MS1 v2.2 board. i'm looking for someone who builds these too, i dont have time to get this and do the ecu build process. i'm not a wiring guy. just an engine tech.

muythaibxr

If you are dead-set on the v2.2 board... I have someone that could probably build it for you, but I'd need to buy the 2.2 kit as I just sold my last one, and don't plan on buying anything but v3 boards from this point on.

If you plan on running low impedance injectors, I'd recommend using the v3 board though, since it has the flyback board's components built in.

Ken

renns

I'd recommend just using the stock resistor pack (or a similar Honda part) to make the low impedance injectors look like high impedance to the ecu. That simplifies the build, and eliminates the flyback issues that are one of the more problematic areas of the MS hardware.

bill Shurvinton

that's the autonomics TB. Very nice piece for the money. Got a few in for some V8 friends and was sorely tempted to build a turbo 12A using one for a hoot.

Only drawback is that they are not very progressive in stock form, but you can change this with an hour and a dremel.

Rex4Life

Roger,

Could you fill me in on the problems with the flyback part? Is that with v3.0 board also?

I currently have HI 550 primarys, and LI 720 secondaries with the resistor pack--so I really don't need it but thought since it's in the kit I'd build it in. Perhaps that's not such a good idea.

Thanks,

Scott

muythaibxr

I've never heard of any flyback problems once the flyback board is in, and the v3 board just has the flyback board circuitry and components built into the board.

I'm not sure that the staged code supports running pwm on just one set of injectors and not the other though..

Ken

renns

Doing a search on flyback problems will reveal a multitude of hits on the msefi forum. Most have had success with the flyback board, but there are still quite a few with issues. I'm sure the V3 board will help, but trying to drive low-z injector directly still puts you in a position where flyback and/or injector driver hardware can be smoked by incorrect software setup. Resistor packs solve that issue with very little downside.

Roger.

pmrobert

I have used low impedance injectors w/ resistors for quite some time - this scheme works very well and is dead easy reliable.

-Mike

muythaibxr

I wasn't saying that the resistor packs don't work... Just saying that the v3 board is more robust and while no piece of circuitry on any piece of electronics is completly immune to failure, the msv3 board is probably much closer than the 2.2 board.

The issues with the flyback board however, as far as I can tell from searching msefi, have been mostly miswiring and bad flyback board installation. The msv3 will protect against miswiring better than the 2.2 circuit, but I suppose nothing is foolproof (the current limiting resistors help, allowing you to basically short the injector driving circuits straight to +12v without frying anything). As for bad installation, as long as the builder builds the v3 board correctly, there won't be any issues with installing the "flyback board" wrong, because all the circuitry is now on the main pcb.

So I agree that there are issues with flyback, but not so much with the circuit design as much as with users misusing it or installing it wrong.

Directly driving low-z injectors ( with properly tuned pwm times and such) does shorten the injector opening time, potentially giving users of large injectors slightly more control over their light-load tuning as well; that's pretty much the only benefit I see to using low-z injectors

Anyway, not trying to argue, just trying to make all the options clear. I don't want to scare people away from driving low-z injectors directly because there are plenty of people who have done it, and have had no problems with it. (I'd venture to say that people have had all kinds of problems with megasquirts, but wired/tuned right, I'd say that the flyback circuitry is no less reliable than any other part of the megasquirt, but maybe harder to tune initially). Any megasquirt (or any other ECU) installation is only as reliable as the installer/tuner makes it.

To get back to the subject of this thread, I'd recommend the v3 board if you can afford it, it's much more robust and has many more options. If money is tight and you plan on having someone else build the board, then the 2.2 board will do fine, and will cost a lot less in pre-built form. (If you build it yourself, the 2.2 kit costs around $140, and the v3 kit around $180, but in pre-built form, I've seen the v3 board go for $90 more than the 2.2 board)

FB II

well, money is kinda tight after getting all the main pieces "minus the MS unit", and i will be using 4 top feed injectors, most likely high imp. so that doesn't really bother me. i just want a unit i can very accuratley tune my afr's with and have good dialy drivability. oh and i can't stress enough...... booooost. does the ms unit use a 3 bar map sensor or anything?

muythaibxr

the MS's stock sensor goes to 250 kPa or about 20 psi. You can get a 300 kPa or 400 kPa MAP sensor that works with it, but I'm not sure where.

FB II

well, i'll be staying put at 16psi on this turbo. i can always upgrade to a high map sensor later then. AWESOME!

FB II

alright, time to get this thread back up now, i realize i actually won't be using "staged injection". all the barrells on this throttle body open simultaneously, is this ok? i know it's great for smooth powerband, just need to know the MS unit is cool with this.

renns

It might work without staging. The potential problem is a lack of tuning resolution at idle when simultaneously squirting 4 injectors rather than just 2. One method to overcome this is a setup scheme known as 'Kurt Staging'. Do a search on megasquirt.info, or msefi.com, and you'll find more info.

FB II

well, i figured out how to make the throttle plates open sequentially. now i need to know, does the megasquirt have throttle enrichment? if so i'm set. because i need it to compensate for when the secondaries open up; kind of like a holley double pumper

muythaibxr

yes it has TPSdot acceleration enrichment, and MAPdot based acceleration enrichment.

Adam R.

wher`s the CAN BUS output in ms2/3 ? Should I search in bd37 ?

SirCygnus

iTrader: (1)

JS6 is CANH, and JS8 is CANL, and to get can but out to the harness, you need to use a jumper to get to SPR2 and SPR1. They are located right behind the db39 connector.

This is for version 3.0 and 3.57 boards.

Adam R.

thanks