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Megasquirt: group buy / assemble ?



I would like to add a couple thoughts since I've built, installed and tuned
a 'Squirt.

> Issues.
> sensor layouts and wiring lengths
> metal fabrication of the enclosure boxes. purchase is easily avail, but
> faceplate cutout is the issue.
> electronic parts assembly and test.
> They use some basic non weather/harsh environment connectors we might want
> to upgrade, cause well - A1's leak.... alot... often ... right on fuse
> boxes..

The Megasquirt cannot be installed in the engine compartment. It's not
sealed in any way and some components are not rated for underhood temps. So,
the "D" connector is no real downside. All connectors in the engine
compartment should be sealed, either stock VW/Bosch connectors or the
appropriate connector for the GM sensors if you go that way (which isn't a
bad thought since it eliminates the need to recalibrate the 'Squirt for the
VW
sensors).

> This only supplies the electronics. we need to find an easy and cheap
> solution for mountable fuel rails for the stock 8v head, stock 16v head,
> the xflow, g60, 20v all have one already. The best solution IMHO would be
> a stock VW part like the late model cabby digi2 fuel rail, but pressure
> issues may be a problem for really high boost apps.

Some data from the Megasquirt list is that the air shroud 8V head can use
injector inserts, fuel rail and rail brackets from the G60 (and this is
exactly what I have on my Scirocco). Apparently, non-air shroud heads have a
different thread for the injector insert and do not have the tapped holes
for the fuel rail brackets. The Megasquirt list may have a solution for
this.
16V rail needs to be aftermarket AFAIK.
I personally don't see any pressure issues. A "normal" fuel pressure
regulator is 3 bar. Running 1.5 bar boost fuel pressure would be 65 psi.
Easily in the range of the CIS fuel pump and not that high in overall terms.
No need to crank up fuel pressure to get adequate fueling since you can
install a large an injector as you need.

> A starting/default map for each of these motors.

Megasquirt comes with a default map that worked fine for starting my
nephew's ABA. The big challenge is getting it started. Once it's started you
can immediately adjust the map based on O2 output.
I don't want to rain on anybody's parade, but sharing maps will never get
you an optimized map for your car. Different cams, different cam timing,
different exhausts, different turbochargers and intercoolers.....all change
the map to some extent. Changing cams can effect the map significantly.Using
different sized injectors will change the map alot.
So, I think everybody contemplating this should be willing to learn how to
use the tuning software to tune their own car. With the Megasquirt it just
isn't that difficult although alot of care will be needed if you're running
a boosted application. NA engine tuning is  simple even using a narrow band
O2. Getting the basic fuel map to a 90% level can be done in ~45 minutes. It
will take time to get the various enrichments right. After all you can only
get one good cold start per day.

just my .02
Dan