Rotate86

as everyone knows injector characterziation has been a new buzz word going around for awhile now.it seems to go hand in hand with ecus that are using VE like the megasquirt.

my question is can someone please show/explain how to set it up in the ms3/ms3x .the only thing i dont understand and its because im not the greatest at maths is how to convert the injector dead times to a % value @ the volts that the megasquirt wants to see.

i know if i was running different primary/secondary injectors i will end up with 2 curves but i am running 4x 2200cc so that makes it easier.
a few model ecus are now including drop down menus to pre select common ID injectors and loads all the data for them.
thanks in advance

Aaron Cake

iTrader: (1)

Which MS version? MS3X allows entering of dead times directly. MS1...that's stretching my memory but I think it's tuned with PWM time.

ID injectors are common so dead times should be available as a starting point but the exact dead time depends on the hardware driving it. So you can start with a known dead time and go from there. Note dead times are only really going to matter at low pulsewidths so you'd be tuning them at idle.

Measuring exact dead times requires some equipment:
Megasquirt-3 MS3 Injector Dead Time Measurement

Rotate86

sorry should try re word this.
i have ms3/ms3x
i know where the data for dead time is entered and how it works.my problem is im not great at maths and have to work out % values from decimals.as the supplied injector dead time is a decimal ms value @ certain voltages.easy to understand, but then the MegaSquirt wants that same data as % values not so easy to me lol.
if you or someone could please show me a example of how the equation is worked out then i can go through and convert my values and know how to do it from here on out.hope this makes bit more sense

Aaron Cake

iTrader: (1)

What data in % are you referring to? Looking at the injector dead times screen, all injectors are entered in mS.

Rotate86

ms3/ms3x tunerstudio 2.6.04

injector deadtime/PWM ,deadtime voltage % curve.

wanted to know the formula to turn the values from decimals to these values but have since had them calculated for me.
if there was a formula to follow others could utilise this with there inj manufactures values.i can follow a formula just didnt know how to get to answers needed.

muythaibxr

The voltage % curve modifies the dead times you enter based on voltage. To get these numbers you either have to ask the manufacturer of the injectors for the data, or get a variable voltage power supply, a graduated cylinder, etc... and measure how much the change in the amount of injected fuel is as voltage changes, and convert that change to a percent.

If you have the ability to take the measurements, post them here and I'll help you convert them to %s.

Ken

arran

If you look at the voltage tables provided by the injector manufacturer you can work out the 13.2V crossing point using the general equation of a straight line:

y=mx+b

I am using XSPERT injectors and my dead time info look like this: