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I have a set of stock ls1 injectors in my motor. It has a return style fuel system whee the ls1 was returnless. I know the flow rate needs to be set the same across the board, but what part of the injector flow rate table do i use. My google search is failing me.
Attachment 68351
Doesn't matter if it has a return or not.
The thing that does matter is if it's vacuum referenced or not.
Mine is vacuum referenced
Take the number on the injectors and look up the flow rate at 58 psi.
A quick search tells me theres four different factory LS1 injectors.
I look up the year of one of my factory LS1 vehicles and find 30 lbs at 58 psi.
I look at the tune file and the closest number I see is 30.1344354623955. So if I put LS1 injectors off my car on my 5.3 truck, I'd start by adding that number all the way across the IFR vs VAC table.
Then see how it runs.
These are the ones I have. 0280155890 26.8@58
So i would use the 26.8 across the table.
Yes.
injector volts offset table needs to be flat lined to suit also
Really?Quote:
Originally Posted by 07GTS
yea because the reg now changes the pressure to suit vac/boost the volts offset/vacuum dosnt have to change to suit either(like the ifr table), the zero column which should be atmospheric pressure just use that column in all columns
Makes sense. Even pulled up a file for a stock vortec and that is the way they are.Quote:
Originally Posted by 07GTS
My understanding tha if the rail is return style it references manifold vacuum and the IFR is flat due to FPR on rail. On the return less rail the IFR table increases.
I have done my own searching and this is what I found. I'm okay being wrong if someone chimes in.
Much appreciated
For referenced always use the 0kpa table
Or 400 for delta
This is an old post.
When tuning in an advanced sense, such as when scaling a tune. Th e injector flow rate table can be used to help 'clean up' areas of the VE map.
For example in my application, even though using referenced regulator, my table is not 'flat'. Instead, I tell it that the injectors are 'larger' in areas of high vacuum, so that it will naturally wander lean when vacuum goes high, like when in decel. This because even DFCO deceleration fuel cut is not 100% effective and "zeroing out" the VE map is only partially effective in regions approaching a full vacuum (which cammed engine in mid-range RPM have trouble reaching) since sometimes you nearly cruise in those areas.
Next, I don't actually put the real value of the injector in the table either. Larger? Smaller? Which way depends on the setup and how much 'tweaking' will be necessary. For example lets say I put the exact injector value in, and everything is a little too 'rich' You can either:
A: re-tune the entire VE map to compensate ("tuning" the engine over time) which will affect transmission shifting behavior thus require even more tuning in other maps once the VE is adjusted,
or
B: Increase the injector flow rate table.
This tells the ecu to inject less fuel, thus it cleans up the VE portions of the map for you (globally reducing fueling). And now because the engine thinks its using the same amount of fuel as before (same airflow from the VE table) the transmission shift wont be affected.
Just depends what you are starting from.