Speeduino ECU's in Buicks?


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Anyone looking lately at using Speeduino ECU devices with our Buicks? I've seen these a bit over the past few years running far newer/more complicated vehicles. As an open-source Linux-y computer guy now with some motorhead roots, seems an eventual evolution vs. the Holley and Haltech ECU's. I'm all for these open solutions like these vs. proprietary.

Really I'm wondering if anyone like Caspers or Bob Bailey have looked into a platform around them. I'm more of a tech guy than car guy anymore, I was looking at putting LCD displays in my GN and things like a Speeduino with TunerStudio if I really bothered with the original v6 at this stage vs just buying a wrecked ZL1 power plant to drop in with more modern conveniences and better support in things like a speeduino.

If there was one thing that pissed me off in more active wrenching days was the janky GM quality of everything on the Regal, particularly the wiring of these, and would feel better off replacing most of the old electronics in a rebuild. I don't want my GN to self-drive like a Tesla, but would be nice to have a modern graphical LCD display and electronics not hamstrung from the 80's.
So there are a few options these days.

Similar to Speeduino is the MS3 Plug n Play. It does hook up to a factory wiring harness but a stock harness is 30 years old and has more hacks in it than you can shake a stick at. Caspers is making a harness to work with the MS3 directly. There have been issues with the 5v fuse popping in the ECM due to grounds I am told but the harness SHOULD fix that. That is the cheapest option out there right now. ECM $1500, Wideband O2 $200, new harness (estimated) $1500.

The ECU GN is next in price and it is a true plug and play deal. You get a tune for your combo from Eric when you buy it. The wide band is built into the system and digital. The software is the same as MS3. It has a scanmaster/Scanmaster G datastream. It comes with a license for TunerStudio Ultra. Caspers has a harness for that as well making it a better deal all the way around. ECM$1900 and that includes the wideband sensor, harness $1500.

Either one of those units will run the DD-EFI dash with a 12.3 inch display off the CAN bus from MS3 or ECU GN giving you a cool digital dash and access to the ECM right on the screen. Comes with a 3D printed bezel so it is a nice fit. Price is $1000

Holley has three ECMs to choose from now based on what you want it to do and Hartline has harnesses made for the Buick to make it all hook right up. Cal is still one of the best in the business and he won't disappoint you. Prices will vary on the ECMs and harness but a ballpark guess starts them at $2500 to $4000 for the ECM, harness $1500 and the digital dashes from Holley will run you $2500 for the 12 inch version.

Don Cruz and Jeremy Oliver both sell and support the Holley system as well and they tune what they sell. They have been using the Holley system for five years or more for sure.

Those are your options.
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^Note the ECUGN includes an integrated wideband O2.
@WIKEDV6 just picked up one of the above mentioned dashboards for his car. I expect we will be installing it in his car in a month or so.