The 1268 kit lacks a fuel pump, also not sure you get the wideband with it either, guessing not or it’d be mentioned.
I had an early Holley projection system on a 440. It worked well enough, but didn’t have the o2 and the mpg wasn’t good. I had a truck with a TQ that ran every bit as good as that system did. Only way I’d consider efi now is with a sensor. I think the options now are cool, but being older and wiser I see them all as being more complication and small improvement for an occasional use car. Occams Razor.
Haven’t seen a throttle body efi that doesn’t have an o2 sensor yet. Most don’t come with a fuel pump. If the do it’s us external. They really should have an in tank pump. External pumps work but I wouldn’t recommend using one. I seen a huge fuel mileage increase when I put the FASt 2000 on my 512 stroker. Having better control of the air fuel ratio helped but I believe having the ability to program the timing curve has the most influence on MPG.
