Thread: IDF Tuning Help
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Old 09-09-2012, 12:34 AM
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Quote:
Originally Posted by jabbott View Post
Couldn't I just keep the same tubes and lower the air jet (same thing as a high speed air bleed on a holey) which would also richen up top, then lower the main jets to get the afr I want.
Yes, you can do that. Main jet ( and to a certain extent, the emulsion tube ) determines A/F ratio at low rpm, air corrector at high rpm.

Emulsion tube affects the "curve" of the A/F ratio between low and high rpm during acceleration.

Theoretically you could nearly obtain the the correct A/F ratio throughout the throttle range with the correct main/emulsion tube/air jet, and then less accelerator pump shot required.

One book of mine states to run air jets in the 60-80 range, then pick the main jet, then choose the emulsion tube. This is all after the correct venturi is chosen for the application.
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Last edited by Gaz64; 09-09-2012 at 12:48 AM..
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