EFI Systems

[Bobby Fazio]

Excited about my new FAST system and still reading instructions while my car is still in Virginia! How does load index differ from traditional speed density? Every track I race puts me at 97.5-99.5 kpa going downtrack so I figured I would change my y-axis to include a row for 97.5, 98.5, 99.5 kpa so I would have a row for any track I race at. When I first started I had a 95kpa row and the next row was 101kpa, so I could never get it exactly right going from a 97.5 track to 99.5 track. It would work for one track then have to be fixed for the next track. The differences between my three new rows are very minimal, just a little bit in the peak torque area just to keep the AF ratio consistent at all the northeast tracks.

Sounds like load index speed density calculates a load percentage based on the difference between Baro and manifold pressure, so does that mean I need an accurate row for (for example) 96%, 98%, 100%, etc.? I'm not yet understanding how the two types are different or how load indexed is the "easier" one to use. I'm guessing at Atco it would be close to 100% while in Norwalk it would be down to 90% or so?