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LS1_Dragster
June 15th, 2008, 09:00 AM
In a drag race only vehicle and you hit 100% duty cycle can you raise the fuel pressure 20% (60psi to 72psi) then reduce your MAP VE 20% accross the board and come out the same AFR? Or is their a different formula to use without starting over on the VE tables?

Thanks,

Lee

ChipsByAl
June 15th, 2008, 09:28 AM
Sorry Lee but it does not work like that. Fuel pressure rise vs. delivered fuel through the injectors is not a linear equation. Check out Russ Collins' web page for an online formula.
http://www.rceng.com/technical.aspx#Find_Fuel_Flow_After_Pressure_Chang e
To be accurate after any fuel changes you should put a wide band AFM to verify the change.
Al

Ritch
June 15th, 2008, 02:22 PM
any concerns about increasing pressure to 70+ lbs? I am considering this.

johnv
June 15th, 2008, 03:39 PM
If your VE table is dialed in you should be able to raise fuel pressure, then rescale injector flow rate table useing one of the spread sheets floating around (do a search)

then you should be good to go :)