Newbie -- help me get un-confused please

A general forum and a place for initial or prospective users. See MSExtra Documentation
Click here to enter
Contact a Forum Administrator
If unsure where to post, post in this sub-forum.

Moderators: muythaibxr, jsmcortina

Newbie -- help me get un-confused please

Postby msdude » Sun Dec 25, 2011 7:42 am

Hi all,

I have decided to Megasquirt a built & supercharged 5.0. Conservative calcs say that I should be getting 530 hp (running 14lbs boost), but I'd be lucky if I were getting half-that currently with the stock A9L processor. My goal for this car is not to squeeze every last drop of power out of it, but rather to get it to idle and run cleanly. The motor is in a kitcar, so don't know what I'd do with that much power in a 2400-lb car anyway.

Been reading and reading, and the folks at diyautotune have been quite helpful, but not sure they have exactly what I want. I want to do this as a project with some high-schoolers I mentor. I've taught them to solder (thru-hole and SMD), do CNC machining, CAD, etc, so ideally we want to do as much as possible. Cost is a factor, and the more I think about it, the more I realize I have most of the parts, except for perhaps the processor and MOSFET drivers. Even have the pressure sensor already. We can layout and order a PCB, but considering what I've read about support etc, it seems smarter to go with the standard bare PCB and build it. Seems the SMD version is only available already-built, so it'll prob have to be thru-hole... bummer.

But version should I be running? One of my first confusions is if I really need sequential fuel. I have a medium cam in the motor and 42-lb injectors, and a lopey idle is fine (and somewhat cool :), but I want it to idle at a decently low rpm, say 700-800 rpm. Would batch get me that? Or would I need sequential? The car is emissions exempt with side exhausts, so a rich and high idle is nasty while sitting at a light. And I'm still a bit confused by the PCB versions. Is the latest MS-II main board v3.0? Where can I get the bare PCB? Any other advice that can steer me in the right direction?

Thanks,
-Neil.
msdude
MS/Extra Newbie
 
Posts: 5
Joined: Sat Dec 24, 2011 7:43 am

Re: Newbie -- help me get un-confused please

Postby dontz125 » Sun Dec 25, 2011 8:47 am

Hi, Neil.

From a student-project standpoint, the V3.0 board is definitely the way to go. This version also includes a 'proto' area for adding customizing circuits, making life a little easier when deviating from the 'standard.' Although, the inveterate smart-ass in me says that for a CHALLENGING project, get a V3.57 board, strip it, then re-install the SMD pieces ... :? :lol:

You don't NEED full-seq, although it does make a noticeable difference to the idle for many engines. Semi-seq will help, and even batch (IIRC) is now able to be 'timed' for better idle and efficiency.

The folks you were dealing with at DIY will quite happily sell you a bare-bones kit consisting of a PCB, processor card, and pressure sensor.
dontz125
Super MS/Extra'er
 
Posts: 1649
Joined: Mon May 11, 2009 7:14 pm
Location: Scarborough, ON

Re: Newbie -- help me get un-confused please

Postby msdude » Sun Dec 25, 2011 3:09 pm

Didn't see the individual parts on their website, but sent them an email earlier today, so I'll find out for sure in a couple days.

In the meanwhile, as I continue reading, I was thinking 3.57 was necessary for sequential, but it seems I should be able to get sequential with an add-on or mod to v3.0. Is this the MS-II daughterboard, or MS-Extra, or...???
msdude
MS/Extra Newbie
 
Posts: 5
Joined: Sat Dec 24, 2011 7:43 am

Re: Newbie -- help me get un-confused please

Postby dontz125 » Sun Dec 25, 2011 3:35 pm

http://www.diyautotune.com/catalog/pkit-megasquirtii-pcbv30-partial-kit-p-93.html

The requirements for sequential include both hardware and firmware aspects. Out of the box, the MS2 (V3.0 or V3.57) with standard B&G code has 2 untimed injection channels and can control one coil driver. The current MS2/Extra code allows for 4 injection channels and 6 coil drivers, with the proviso that you have to modify the hardware yourself. Note that this does NOT include sufficient injector or coil drivers for full-sequential fuel or spark on a V-8; you are limited to wasted spark and semi-sequential injection.

Conceding that I have never so much as laid hands on a V3.57 board, I would suggest that it is likely HARDER to mod for the extra channels. If you are starting with a bare V3.0 board and a selection of parts in your wokbench, I would recommend you investigate the 4-channel driver board by Jean Belanger; http://jbperf.com/quad_ign_inj/index.html. Note that you will also need to make a minor mod to the MS2 card to use the additional injector channels; http://jbperf.com/sequential/index.html#ms2mods

The other option is of course to install a MS3 processor with a MS3X expander card, which will allow you full sequential injection and spark control for all 8 cylinders. It is however more expensive, and rather less of a DIY project.
dontz125
Super MS/Extra'er
 
Posts: 1649
Joined: Mon May 11, 2009 7:14 pm
Location: Scarborough, ON

Re: Newbie -- help me get un-confused please

Postby msdude » Sun Dec 25, 2011 10:03 pm

This is actually nicer, so I can deal with this later if I need it. Agreed with the MS3/3x... price is considerably different now. Still have much to read, and I'm in the middle of Matt/Jerry's book also, but getting anxious now since my high-schoolers have much spare time currently, and the 3D printer project is almost done. Thanks for all the info ... so far :)
msdude
MS/Extra Newbie
 
Posts: 5
Joined: Sat Dec 24, 2011 7:43 am

Re: Newbie -- help me get un-confused please

Postby aarc240 » Tue Dec 27, 2011 6:06 pm

I'd suggest doing a full cost analysis of the whole project before deciding on the base EMC board version.
This is a time when a spreadsheet is your friend so do a complete-in-every-detail theoretical build each way and see where you're at.
Without doing that, you may well assume that the MS3+MS3X is an expensive option but there are the external systems to consider.
Assuming you opt for 3X and full sequential spark, you can get GM LS2 truck coil packs new for surprisingly little ( <$150 for 8 ) on the Internet whereas if you go another route you may well spend $300 or more just on a decent ignitor and coil combination.
The v3.0 board is decidedly more flexible and user friendly in customising to suit the target vehicle than the v3.57 SMD board.
Art,
Datsun 260z 2/2 with 280z/MS3+/5spd for the road
Datsun 240z with 280z. nearing the road again
Nissan E24 Urvan with 260z/Megajolt/5spd parts hauler - sold
aarc240
Helpful MS/Extra'er
 
Posts: 111
Joined: Wed Jun 01, 2005 3:11 am
Location: Australia

Re: Newbie -- help me get un-confused please

Postby Ollie8974 » Sat Dec 31, 2011 6:10 am

Some thing to remember, The 3.57 board is fully assembled.
I would recommend the following components to give the students the most experience with the assembly process.
These components are available in kit form.
MegaSquirt - III with PCB v 3.0 unassembled.
Daughter card kit MS - III MS 3X expansion card
Either the MegaSquirt Stimulator 2.2 kit, or
The Jim Stim 1.5 MegaSquirt Stimulator with wheel stimulator kit.
MegaSquirt Relay Board, kit.
Ollie8974
Helpful MS/Extra'er
 
Posts: 121
Joined: Tue Aug 05, 2008 8:47 am


Return to General, New users, Purchasing

Who is online

Users browsing this forum: Google [Bot], Yahoo [Bot] and 1 guest