Simplest EFI setup

[Fred]

Check these out: http://14point7.com/SLC-OEM.php

They don't come much more compact, cheap and accurate than that :-)

[nimblemotors]

that is a good point about the oil-based air filter, which I'd like to continue to use on the tractor.
So sounds like a MAF isn't going to be reliable, then I guess I must do MAP.
Yeah, the wideband for tuning it up would be good, that link looks like what I need, a simple 0-5v output that I can use.
thanks

As I said above, you will want to use a wideband to set it up in the first place. After that, though, you don't need it. Without it, you're almost doing as badly as the old carby days, possibly worse as EFI, especially with custom code that's untested, has the ability to do wild extreme things that a physical carby that's roughly the right size and jetting simply can not do. Size the MAF to match the power for best accuracy and finesse of control. So, likely quite small for that engine with its poor flow, I guess. Choose carefully, though, MAFs can be pretty unreliable if not treated right.

Also, hot wire/film MAFs can't be used with K&N style oil based filters and are VERY sensitive to oil residue and FLAP meters have issues with not being horizontal, etc.

If you're taking TBI from an engine, and it's suitable, then the MAF is likely to be well matched too. If one also isn't, the other probably isn't.

Fred.

[Fred]

Another thing is that MAF is not tolerant of air leaks, and MAP is. I may have mentioned that above. Flap MAFs tend to wear out their pots too. I should have that wideband in my hands very soon, so I'll let you know what I think :-)

Most are 0-5, some have digital options. This has I2C and it's well documented and, Alan, very kindly, is about to make it MUCH easier for us to interface with! :-)