Waterproofing Megasquirt?
 

As winter approaches, I'm getting ready to officially start installing my turbo build parts. I want to start with installing MegaSquirt; I know the OEM ECU is fairly protected by an elevated brace + carpeting and soundproofing, but the MegaSquirt mounts a little differently. I'm concerned about water getting to it; I've already had one A/C hose clog that resulted in water spilling into the passenger footwell.

I'm from Montreal and we get a fair amount of rain as well. Am I being paranoid about wanting to waterproof the MS? If not, what have some of you done to ensure your $1000 ECU stays dry and safe ;p ?

Where are you mounting it that you're worried about water? I can't think of a single OEM location that wouldn't involve the car being under 2' of water to actually touch the ecu.
the ms-pro is also waterproof

You can use a Singular (or homemade) bracket to mount your MS in the OEM style, slightly elevated from the sheetmetal and protected by the cover and carpet.

Singular Motorsports Miata ECU Bracket for Miata 1990-1993

OEM location, just worried about my AC getting clogged and sprayed out on top of the MS from under the glove box.

IIRC, in a 1.6 the ECU is under the passenger-side carpet, I could see it getting damp there in the event of a leak.

To waterproof a non-pro megasquirt you basically need to encase it in a waterproof container and then seal the hole where the wires come in somehow. Theoretically you could do with a gasketed box and a bunch of hot glue around the wires, but it's really not practical. If you really care, you'll have to buy an the pro and put the waterproof connector onto the factory harness.

You're being paranoid. If you were building a Locost/Exocet/Catfish/etc style of kit car, then this might be a real concern when driving the car in the rain. A race car that has compromised waterproofing and needs to be reliable in the rain might also be a concern.

--Ian

Thanks for the advice Ian. I think I'll put my mind at ease with a very basic plastic covering over the ECU itself, just just just in case. Cheers

Ms3-pro is the solution. Plastic cover will get you some of the way. If I ever build an exocet in Oregon it will get an ms3-pro

Just put a plastic bag/box over it with the opening pointing down. Unless the footwell somehow fills all the way to the dashboard, this will be enough waterproofing in the event of a clogged AC drain hose or something.

Zip-loc. Stop over-engineering things.

my car would leak water directly to the passenger foot-well when it would rain...

And a bag or something over the ECY would be enough to keep it dry unless the footwell filled up.

I don't think I've ever seen a Miata MSPNP sent back for repairs with water damage, and we've been selling them for nine years now. Almost all ECUs I have seen sent back with water issues were either installed in the engine compartment, or the victim of a boating accident.

your Miata was a heap that had many other issues too, so..........

:D

I would consider dipping the whole unit in hot wax to seal it.

Flex Seal from a home improvement store. It's how I waterproofed the ECU for my 1990 way back when it would always leak water into the car after a storm.

Waterproofing a MS thread and nobody has mentioned duct tape yet?! Blasphemy!