@Bjorn Nilson , after further research I completely agree. The MegaSquirt info says the same; you need a decent computer to do tuning, settings, etc. But for just gauge display a Android will work. I don't recall seeing any specific MegaSquirt requirements for computing power - although I'm sure there is somewhere. But they do talk about issues when trying to do more with less (so to speak).
From what I've read the whole CANBUS thing seems rather complicated, at least for someone like me that isn't knowledgeable with such things. And the CANBUS gauges tend to be very modern "digital" numeric displays, not old school looking analog sweeping needles like I want. Not to mention they are rather costly. So I might as well use the tablet approach.
There are a couple of specific brand/model of some gauges/senders that will feed both the ECU and the matching dash gauge. However none of them appeal to me for various reasons; modern numeric display, poor reputation for reliability/issues, incompatibility with the rest of the system I'm using, overly expensive, etc. And they are only available for certain functions, not necessarily the ones I'm interested in.
As I said previously I'm going to use standard style gauges for most functions (as part of the whole build esthetic). Really the only extra displays I might want to add are the AFR, boost level, and IAT. However I'm not even decided on some of those. The IAT would only be to see how the engine is managing thermal load with the turbo system. Other ways to look at this might be EGT, or multiple sensors for temp differentials in particular spots, etc. But once everything is properly tuned safely this really isn't needed. So I might just use datalogging reviews to check it until I'm comfortable things are under control. And not worry about a gauge for it. Same for boost level. I really just want to make sure the boost controller can prevent creep and maintain a safe level of pressure under most conditions. So once things are looking consistently good then I won't worry about it much and a gauge is no longer needed. Keep in mind I am not building a "performance" engine or race vehicle as much as supplementing the stock SOHC with a little extra "drivability" for regular street use; low boost, small turbo, lots of thermal management, conservative tune. Therefore once I know things are not detonating or overheating then I just want to drive it like a normal car and don't really need a ton of gauges to look at. The AFR might be one exception, because of its criticality and variables that may not be easy to always control (fuel quality, ambient temp, component failure).
I'm also thinking rather than mount a tablet into the dash, I may temporarily use my phone to read a couple of functions during the set up and sorting stages. It could be held with one of the common phone holders that are easily removed.
Another thought is to set some warning levels in the ECU to trigger a light and/or buzzer in lieu of gauges. It would be nice to combine all of the warnings to feed one red light right in the middle of the dash's field of view. I saw a small surface mounted warning light and buzzer combination that might be used. They are available in various sizes:
Really when you think about it gauges are only good when you are looking at them. And it's when you are driving silly - a time when you will be focused on the road and not the gauges - that things tend to go wrong. So 'displays' are not necessarily the best failsafe.
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