how much fuel does a chip pull out for acoh
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typically 10-15% pulled out , but if working with an existing chip or program it depends on what new expected boost level you plan to run vs what the old chip/program was set for
typically a street chip burned for 93 octane(no alky) will have fuel to support 17ps
the alky chip to run 21-23psi will have similar fuel levels as the street chip but with more timing and depending on your kit (progressive or not) it may be tweaked further at the bottom
tt chips let you tweak the timing and the fueling if still within the 100% duty limit of your injectors and the limits of your fuel pump
AF is a better way to determine fuel needs . i like 10.9-11:2 AF with enough alky to not knock ,tuning for mph
typically a street chip burned for 93 octane(no alky) will have fuel to support 17ps
the alky chip to run 21-23psi will have similar fuel levels as the street chip but with more timing and depending on your kit (progressive or not) it may be tweaked further at the bottom
tt chips let you tweak the timing and the fueling if still within the 100% duty limit of your injectors and the limits of your fuel pump
AF is a better way to determine fuel needs . i like 10.9-11:2 AF with enough alky to not knock ,tuning for mph
Actually.. the question cannot be answered the way it was asked. The reason is that chips dont pull out fuel.
If your tuning using a DFI and have the car tuned at 25 boost.. then you put the alky on that car staying at 25 PSI.. the amount of fuel that will need to be pulled will be depending on the octane used. A car runnng 93 octane will need to be on a heavier diet of alcohol vs a car being run on 110 will need less.
Rule of thumb is 15% as starters. Meaning if your injectors are at 80% DC then you typically can put them to 68-70% DC and be close to start.
Now as to chips.. a 16 PSI street chip will support 25 PSI with alky.
Once a MAF hits 255, the computer no longer knows how much air is going through it. So if it hits 255 at 16 PSI.. then the computer at that point just opens the injectors to what ever target was set on the chip when it was made.
HTH
If your tuning using a DFI and have the car tuned at 25 boost.. then you put the alky on that car staying at 25 PSI.. the amount of fuel that will need to be pulled will be depending on the octane used. A car runnng 93 octane will need to be on a heavier diet of alcohol vs a car being run on 110 will need less.
Rule of thumb is 15% as starters. Meaning if your injectors are at 80% DC then you typically can put them to 68-70% DC and be close to start.
Now as to chips.. a 16 PSI street chip will support 25 PSI with alky.
Once a MAF hits 255, the computer no longer knows how much air is going through it. So if it hits 255 at 16 PSI.. then the computer at that point just opens the injectors to what ever target was set on the chip when it was made.
HTH
Now I'm confused. 
And trust me, I'm a total rooky when talking "alkyspeak".
In the limited knowledge I have it's been conveyed to me that if a car likes 11.5:1 at a given boost and given octane.
Shooting alky, one should shoot for a 10.8:1 or richer mixture, all things being equal.
That sounds like adding fuel, not lessening. What am I missing?
And trust me, I'm a total rooky when talking "alkyspeak".
In the limited knowledge I have it's been conveyed to me that if a car likes 11.5:1 at a given boost and given octane.
Shooting alky, one should shoot for a 10.8:1 or richer mixture, all things being equal.
That sounds like adding fuel, not lessening. What am I missing?
Typically when you have an engine tuned to 11.5:1 and you switch on an alky kit, the air fuel will drop to like 10.0:1. So you reduce injector DC and lean it out to 10.7. Makes sense.
To only make a .7 drop in air fuel takes very little fuel.
Remember its all about how much alcohol is needed to support the goals.
A motor trying to run 2-3 PSI over stock doesnt need as much as a motor running twice the stock boost level.
Now the higher the amount of alcohol used, the lower the target will move. As methanol has a lower stoich.
In the end one tunes for maximum HP. And one tunes fat to lean. So starting a tuneup at 10.0:1 isnt an issue.
To only make a .7 drop in air fuel takes very little fuel.
Remember its all about how much alcohol is needed to support the goals.
A motor trying to run 2-3 PSI over stock doesnt need as much as a motor running twice the stock boost level.
Now the higher the amount of alcohol used, the lower the target will move. As methanol has a lower stoich.
In the end one tunes for maximum HP. And one tunes fat to lean. So starting a tuneup at 10.0:1 isnt an issue.
