Megasquirt users thread to discuss all things Squirty

[The Witzl]

i tend to recycle old looms Chuck.... i have a few shelves in a cupboard in the garage of wiring looms pulled from various front cuts and stuff, and just pick suitably sized wires with enough uncut length.

Never really bought many regular wires, other than specific use stuff like VR signal wires, or heavy gauge stuff.

[MWP]

Ill be buying one or two lots of the loom wire from diyautotune when i buy the MS3 stuffs.
http://www.diyautotune.com/catalog/m...ong-p-452.html
Should make building a loom quite a bit easier, and also easier to work with & modify in the future.

There are other companies in the US that sell loom wire bundles with assorted colors/stripe patterns at reasonable prices.

[oldcorollas]

Thanks Roger,
I might just use the toyota igniter... vibration resistant, already connected, no need for extra wires...
the MS1 tach sense line is single core sielded, with mono audio plugs in it with resistor needed to damp the coil spikes... if ya know what i mean, so it can be easily switched out.
actually thats how i had MS2 running before..
actually the tach sense line goes to the ignitor, with a wire between that and coil, so is easy to take off coil. tacho sense is at the coil, so that doesn't need to change either....

i will go the BIP as well, as i have a single wire running to coil, that was an ignitor trigger before, so should be easy to swap it around for the BIP duties.

Karl, JBperf would be good, but adds $. will prolly get one of his dual boards for next build (when i don't want to think abotu $ spent )
I'd still be tempted to have the VR conditioning closer to the VR, as it's signal out is more robust..
yup, aware of ground loops, all good.

is weird, it used to be really straightforward and easy to read up on, but now there is sort of too much info. then again, i started by back reading 20,000 yahoo mailing group posts before the first US GB for MS1
i think just sticking to one version, and reading itS' manual all the way thru helps. start from MS1, then move to the others.
the MS is all abotu understanding what ti does and why and how.

new car looms look really good, although they are all going to thinner and thinner gauges these days.
yup, i'll grab one of those MS looms for next build, makes it too easy.

chuck, other way is to have relays just behind the headlights, so you just need one bigger power wire to each corner, then signal wire to the headlight relays. 4 relays, but less wiring in total.

[MWP]

Talking about looms... is there any reason the MS ECU couldnt be located further back in the car?
Im considering mounting mine behind the passenger seat next to the battery (and possibly relocated fuse box).
I guess that will add an extra ~1.2m in loom length from the standard firewall positions.

[oldcorollas]

no, not that i can think of.
the MAP line can be quite long and have little effect, but if you were ultra worried, you could remote mount the MAP sensor..

wires should be no probs at all.

[thechuckster]

agreed, the MAP line can be quite long. Some of the early Megasquirt guys did a test with (i think) an 8 foot long house and found no appreciable delay with the MAP air 'signal'.

Stu: I think I'll have to go that route (remote-mounted relays with a single power line) - will help eliminate some of the in-cabin wiring mass.

[3jcelica]

MWP,

basically the closer to the battery the better (reduces noise)

Oldcorollas,

Forgot to mention you need a pull up resistor to 12v on the tach signal when comming out of the toyota ignitor.

Roger

[MWP]

MWP,
basically the closer to the battery the better (reduces noise)

It also increases the length of the signal lines (VR sensors, map, etc) which increases noise
Im sure i can work around any problems though.

[oldcorollas]

if they are shielded, and not running near noise generating things, it should be ok no?

fwiw, i run signal on one side of engine bay, and injectors (and coil) on other side, to reduce possible issues.

thanks Roger.. i think i must have had one in there before when testing the MS2... easy to put one between + and - ont he ignitor anyway (is mounted to side of dizzy). I hoep i remember to fit one again

[oldcorollas]

ordered.. 1MS2 board, 2 BIPs, couple of weatherproof connectors... $40 postage fee
oh well, is only money

was going to get LC-1 but they are out of stock atm? hmmm

[thechuckster]

Who did you order thru?

edit - just read the DiY autotune site, you could just get a MTX-L as they're basically a gauge with the controller stuffed inside it (just check that it does the free-air-calibration thing).

On the subject of wideband sensors, I grabbed a PDF of a review of sensors done by the FordMuscle website that was linked to on PF. Is a 596Kb PDF so can email to anyone interested (or put up online somewhere).

[oldcorollas]

DIY. (tbh, i didn't look for any others... next time would be nie to have JBperf VR at same site as a daughterboard )
yeah, looked at the MTX-L.. do they have a plug between the sensor and the long cable? no plug= annoying to drop exhaust
i won't be running it as a permanent sensor, so was a little put off by having to have the gauge there.. i suppose you can pretend it is not a gauge tho
maybe in next round of splurge..

review of sensors? ie bosch vs NTK? or of wideband controllers?
this one? http://3000gt.com.au/car/Emanage/Wid...20Shootout.pdf

[old_mr2]

Hi squirters,

What is good desktop power supply for powering up one of these away from the car? Jaycar/ebay link would be appreciated.

[knightrous]

Hi squirters,

What is good desktop power supply for powering up one of these away from the car? Jaycar/ebay link would be appreciated.

I use a PC power supply with a 1amp fuse in the output.

[oldcorollas]

i use an old computer power supply.. yaknow, the ones where you could turn it on with a button
can you mod the newer ones that have the "soft" on switching?
you want it to be a regulated supply (iirc) so it actually stays at the voltage it is meant to.

1A fuse is a good idea!