Any opinions about this AFR table for my EFI system?
351C, 4V heads (unknown type of chamber), Torker manifold modified for port injection, 3/4 race cam, GTS headers and mufflers.
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Overall the chart is not too bad. Here is my take.
Idle may be a little rich depending on the cam. 14 might be better.
The cruise range is a little lean at part throttle. 15 is too lean for the power range. You will need to determine the MAP range you will run at cruise. Set your 15 at that range and just above. Then taper to the power ratio. For starters until you see how it will run and perform, I suggest no less than 14.7, even though 15 is really close enough.
I dont suggest the 16 at the bottom of the chart. Unless your engine is designed for lean ratios, you can cause stumble when you return throttle.
The other thing I notice is you only go to 50 kpa on the bottom of the chart. This is 15in hg. You should get better than that running. You need your chart to go to at least 30kpa on the bottom.
Idle may be a little rich depending on the cam. 14 might be better.
The cruise range is a little lean at part throttle. 15 is too lean for the power range. You will need to determine the MAP range you will run at cruise. Set your 15 at that range and just above. Then taper to the power ratio. For starters until you see how it will run and perform, I suggest no less than 14.7, even though 15 is really close enough.
I dont suggest the 16 at the bottom of the chart. Unless your engine is designed for lean ratios, you can cause stumble when you return throttle.
The other thing I notice is you only go to 50 kpa on the bottom of the chart. This is 15in hg. You should get better than that running. You need your chart to go to at least 30kpa on the bottom.
Your first table was really better than the second. Just need to change the Map values on the left like the second table, and bring the ratio a little richer where the 15s are.
Here is the fuel map. Notice that the really rich region is quite small. The 15:1 is set for typical cruise. The idle is a little rich because of your cam. If you have stumble off idle, you might need to richen it up a little. The map looks lean but with EFI you can do that. Most carb engines are rich because you have to due to carb limitations.
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