Homebrewed MS3-Pro DIY BOB
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From: Meridian, ID
I picked up an MS3-Pro on Black Friday and am building a short PNP harness rather than cut up the 8’ long generic harness that came with it.
Following are the TE Connectivity part numbers for the connector housings and terminals as well as current pricing from Onlinecomponents.com.
- AMPSEAL white 35 position connector housing – part number 776164-2 / $8.12 each
- AMPSEAL gray 35 position connector housing – part number 776164-4 / $8.14 each
- AMPSEAL tin contact – part number 770854-1 / $0.09 each
$23.01 in total for the two connector housings and 75 contacts. Onlinecomponents.com has a $30 minimum order, so I added a 64 pin ECU connector for $11.96 (part number 174518-7).
I also found a breakout board for $10 shipped here ecu-64p-connector-bare-pcb.
Following are the TE Connectivity part numbers for the connector housings and terminals as well as current pricing from Onlinecomponents.com.
- AMPSEAL white 35 position connector housing – part number 776164-2 / $8.12 each
- AMPSEAL gray 35 position connector housing – part number 776164-4 / $8.14 each
- AMPSEAL tin contact – part number 770854-1 / $0.09 each
$23.01 in total for the two connector housings and 75 contacts. Onlinecomponents.com has a $30 minimum order, so I added a 64 pin ECU connector for $11.96 (part number 174518-7).
I also found a breakout board for $10 shipped here ecu-64p-connector-bare-pcb.
Over head of having a building and staff, getting metal cases made, keeping capital tied up in having inventory, R&D costs. DIY charges what they do because that is what the market will pay for. You are paying more for the convenience of getting it all from 1 spot already done for you.
I'd be super down to buy this if I could find a decent enclosure for it, and if I could figure out how i'm going to mount the megasquirt that close to the ECU cable. I wasn't able to find a spot when I originally put it there... ('00)
Haha, I took advantage of BF to buy a MS3pro module, two map sensors and four bip373s. Im mounting it inside the original Mazda ecu case. I thought about getting Franks adapter boards which are awesome but it wouldnt work with my extra uotputs.
Anyhow, havent done much but preliminary mounting of the boards and placement of the bips. Did snap a pic of it though.
Anyhow, havent done much but preliminary mounting of the boards and placement of the bips. Did snap a pic of it though.
Thread Starter
Junior Member
iTrader: (42)
Joined: Dec 2010
Posts: 278
Total Cats: 21
From: Meridian, ID


Maybe DIY uses the $.63 each gold pins because we care more about doing this the best way possible instead of the cheap $.09 each tin pins.
Maybe next time thank companies like DIY for providing all of the R&D, tech support, and forum sponsorship before bad mouthing. Last I checked, online components doesn't help pay for the sandbox you enjoy playing in.
Maybe next time thank companies like DIY for providing all of the R&D, tech support, and forum sponsorship before bad mouthing. Last I checked, online components doesn't help pay for the sandbox you enjoy playing in.
this is confusing to me. where would those connectors connect to? the ms3pro? why not put that pro inside that case then and not use the two connectors?
Thread Starter
Junior Member
iTrader: (42)
Joined: Dec 2010
Posts: 278
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From: Meridian, ID
No reason really other than that I've got the standalone version of the MS3-Pro and would need a bigger case. Don't know yet if I'll have sufficient space under the dash where the ECU goes. At 2 am last night it seemed logical to put the MAP sensor, USB port and whatever else in the space provided for in the case and just run an extension harness between the case and the MS3-Pro, wherever that ends up.
Thread Starter
Junior Member
iTrader: (42)
Joined: Dec 2010
Posts: 278
Total Cats: 21
From: Meridian, ID
Maybe DIY uses the $.63 each gold pins because we care more about doing this the best way possible instead of the cheap $.09 each tin pins.
Maybe next time thank companies like DIY for providing all of the R&D, tech support, and forum sponsorship before bad mouthing. Last I checked, online components doesn't help pay for the sandbox you enjoy playing in.
Maybe next time thank companies like DIY for providing all of the R&D, tech support, and forum sponsorship before bad mouthing. Last I checked, online components doesn't help pay for the sandbox you enjoy playing in.










