Printable View
I see people all the time say add 10, 20, 30 percent more fuel. How do you do that in Hp Tuners? Like how would I add 10, 20 or 30 percent to fueling with the ve table? I normally just log and tune, never added a percentage of fuel before logging.
I have never had to do this but I want to understand how to.
You chose the area that you want to ad the fue(ex so many grams of air and the rpm area) you highlight the area and you multiply it by 1.1 that's 10% 1.2 would be 20%so on
Adding a precentage is as easy as multiplying by 1.xx where xx is the percent you want to add. 1.10 will add 10%. 1.20 will add 20% and 1.30 will add 30%. this can be used for any percentage you want. for example, adding 24% is as easy as multiplying the current value by 1.24.
Why would you want to add to the VE like that? Just creat a graph and it will add the presise amount to the exact place it needs it!
For some situations, like getting the engine to simply idle when the tune is known to be way off after heavy modifications. It can be necessary to "ballpark" the numbers enough with this method and then use the power of the scanner to bring the numbers where they really need to be.Quote:
Originally Posted by JIC_Bro
Thats what I was going for. I am going to be doing my e85 tune and would like to start in the ballpark. I also wanted the knowledge in general.Quote:
Originally Posted by Calnom
Should I start by adding 30 percent to the PE table if trying out E85?
I am not an expert on e-85 by any means, but if i understand the system properly, this will depend on which OS you are using. if all you are doing is switching to E85, your airflow numbers will be the same. Early OSs like the one i used in my truck (an 01 silverado OS on an 0411 PCM) SHOULD only require changing your base stoich AFR value to the target fuel. (you can find this value in some tunes or even on wikipedia) More recent systems have a scale that expects input from a sensor or calculates based on your fuel tank refill and how the change in fuel trims indicate which fuel you put in. i recommend against adjusting airflow numbers to compensate for a change in fuel.
It is on a 00 Sierra. I wasn't sure if changing stoich to 9.7 would ballpark proper fuel or not. Not like it's hard to add 30 percent know that I know how.
It should. The stoichiometric value is really a descriptor of the fuel and all the other calculations are based off of it. Theoretically, you can put any fuel through the engine and adjust the one value and the system will scale to the run the same. Of course the capabilities of the fuel system would be limiting factors.