7747 on a Ford 400 - still not getting a backfire issue sorted

[Dr_Grip]

hy, this may not be a problem or it may be the way it works on a conversion. to me it looks like the tps and map voltage don't corrusponed to each other as on a stock chevy. seams the tps is reading a little low or the map is reading a little high. if you use the digiatal dash you can put them side buy side and watch. it may not be anything wrong but one of the sensors may be lazy. I don't know if this will help or hurt, if you are running lets say 10 btdc at idle try setting inicale timming in your bin to what it is set with a timming light at the crank pully. I think it not only affects the spark but also when the injectors fire.

MAP values definitly are different from a Chevy engine (and even from a Ford Windsor). The Cleveland/M-Block is an... interesting engine, to say the least (some people claim the M-Block plainly sucks). You can see how I had to change MAP values for DFCO to get it to work, for example.
Timing's set to 0° on the engine and in the bin. I've checked multiple times, spark advance according to hack in the log file matches what I see on the pulley +/- 1°.