Injector offsets

[Frosty]

So in the hopes of being able to install my 60lb siemens injectors without massive maf changes iv spent the last 5 hours trying to figure out the proper settings for these injectors. I have found numerous pdfs and whatnot that supposidly have the info to properly tune my offset vs volts and offset vs pw vs map tables. I cant for the life of me find out how to convert these numbers into something to fill my tables with. I already am setting my FPR at 43.5 so I have the flow rate set to a flat 60 across the table. I have managed to find some decent info on the voltage offsets...

6 - 2.59
8 - 1.441
10 - .921
11 - .758
12 - .636
13 - .518
14 - .409
15 - .312

For the life of me I cant figure out the Offset vs pulsewidth vs map. The most useful info I have found is that similar injector styles are much closer in offsets vs pw and therefor I currently plan of running a 2001 GT offset vs pw vs map table because it has the very light and fast multec injectors in it which are very similar to the siemens 60lbers.

• Coil Resistance: 12.5 Ohms / High Impedance / High-Z (No ECM driver modifications required)
• Static Flow Rate @ 43.5PSI ( 300kPa ) w/Gas: 60 lb/hr = 630 cc/min = 453 g/min
• Static Flow Rate @ 87PSI ( 600kPa ) w/Gas: 85.7 lb/hr = 900 cc/min = 648 g/min
• Gain: 0.11ms/mg
• Offset: 0.055ms
• Turn on time @ 14VDC: 1.14ms
• Turn off time: 0.85ms @ 600KPa
• Series: DEKA 4 ( DEKA IV )
• Orifice Type: Multi-orifice
• Spray Pattern: 30 Degree Spray Cone
• Factory fitted with Viton upper and lower o-rings

Has anyone actually gotten the real info for these or know how to take this spec sheet and turn it into these tables? I feel like im really not asking that much to be able to install these without having 10 - 20% fuel trims.

:th_angry-teeth:

 

[moddman]

Look for injector.xls online. Use Google.

 

[darkhorizon]

I have found numerous pdfs and whatnot that supposidly have the info to properly tune my offset vs volts and offset vs pw vs map tables

These will be misleading because the offsets in our PCM's are not "typical", as the minimum injector time is used in combonation with the offset.

That being said... #60s/80s/100s I have tuned in 20+ cars have never required maf tuning or injector offset changes.

Also,

You posted all the information you needed.. it has base injector time in the listing (1.14 ms @ 14v) so if you scale the offset table (use the stock curve) to match based on the minimum pulsewidth you will be fine. Depending on what file you have, the min pulsewidth will be different, most of them are 1.3ms... so your current base injector pulsewidth is 1.7 at 14v.

The basic math for figuring IPW is based on something like base MS (1.3) + offset(.4) + magical fuel number (???). The magical fuel number uses the calculated base MS to some degree, but it uses it from another location in the pcm... so it makes tuning base injector data in a fwd v6 pcm more or less impossible.