Offset Voltage data

A1C calibration can be modified and configured to operate all EFI-SD4x ECUs in 4 cylinder, 6 cylinder and 8 cylinder configurations.
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Offset Voltage data

Unread post by efloth »

Trying to get the injectors dialed in perfectly. Is this accurate? I am currently running 8% higher than this for 52PSI

http://www.usa.vdo.com/media/747302/fi1 ... ksheet.pdf

Should these numbers be different when using speed density/batch fire?
dleach1407
Posts: 468
Joined: 2021 Mar 21, 15:17
Location: Colorado Springs, CO
Vehicle Information: 95 Mustang GT, CBAZA Quarterhorse
331, 190 11R heads, Edelbrock Victor 50 manifold, F303, T5, 76mm Turbo, 91 octane, Returnless dual pump 03 cobra tank, Behind bars rails, 80# siemens injectors
wbo2_030MtxL

57 F100, RZASA, 04 Crown Vic ecu and harness, 302, GT40 heads, 4r70w, 80# deka5 shorties, Holley carb style throttle body, Speedmaster high rise intake manifold

Re: Offset Voltage data

Unread post by dleach1407 »

If you are running Siemens 80s, the best info is the ford info found below

https://performanceparts.ford.com/parts ... 3-lu80.pdf

They have data for 50, 55 and 60psi. If you go to 55psi you can calculate everything using the multiplier for 54.98 lbs.
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: Offset Voltage data

Unread post by efloth »

You the man! Thanks
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: Offset Voltage data

Unread post by efloth »

Diving into this today: How do we explain this discrepancy? First chart is Decipha's listed offsets for Speed Density @ 30PSI. .8722 is the multiplier for 30 PSI in the document you linked. @ 15v take .454/.8722 = .5205 != .721

Should I just take .5205 * 1.1883 to get speed density offset for 15v @ 55PSI? Hope this makes sense.

Code: Select all

FRPP 80 lb/hr @ 30psi
LU80
Siemens Deka 80 lb/hr @ 30psi BASE
K-Constant	30.00
High Slope	65.552
Breakpoint	0.00002119
Low Slope	65.400

VOLTAGE OFFSET
voltage	ms
16.00	0.454
15.00	0.454
14.00	0.505
13.00	0.569
12.00	0.641
11.00	0.720
10.00	0.812
8.00	1.120
6.00	1.772
0.00	1.772
0.00	1.772
0.00	1.772

Code: Select all

FRPP 80 lb/hr @ 39.15psi
LU80
Siemens Deka 80 lb/hr
K-Constant	30.00
High Slope	75.157
Breakpoint	0.00002421
Low Slope	101.459

VOLTAGE OFFSET
voltage	ms
16.00	0.721
15.00	0.721
14.00	0.801
13.00	0.903
12.00	1.017
11.00	1.142
10.00	1.288
8.00	1.777
6.00	2.811
0.00	2.811
0.00	2.811
0.00	2.811
dleach1407
Posts: 468
Joined: 2021 Mar 21, 15:17
Location: Colorado Springs, CO
Vehicle Information: 95 Mustang GT, CBAZA Quarterhorse
331, 190 11R heads, Edelbrock Victor 50 manifold, F303, T5, 76mm Turbo, 91 octane, Returnless dual pump 03 cobra tank, Behind bars rails, 80# siemens injectors
wbo2_030MtxL

57 F100, RZASA, 04 Crown Vic ecu and harness, 302, GT40 heads, 4r70w, 80# deka5 shorties, Holley carb style throttle body, Speedmaster high rise intake manifold

Re: Offset Voltage data

Unread post by dleach1407 »

You don't use your offsets in the ecu, you would use the data in the voltage offset column on the .pdf and then multiply it by .6303 which is the offset compensator for 30psi

You do the same thing for high slope, low slope, and breakpoint using the corresponding compensator for each. If the info is already on the home page i would just use that.
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: Offset Voltage data

Unread post by efloth »

I don't think you understood. The offsets I posted for 30 psi (speed density) were from here: http://efidynotuning.com/injdata.htm

if I take the high slope numbers in the pdf you linked * .8722 they don't match with decipha's. Trying to figure out what gives. Speed density is single slope so the other info is irrelevant in this case.
decipha
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'19 F-150 3.3L

Re: Offset Voltage data

Unread post by decipha »

it matches perfectly

.8722 is for the high slope only

The offset gets multiplied by .6306
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: Offset Voltage data

Unread post by efloth »

Ok so use low slope numbers for AHISL?
decipha
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'19 F-150 3.3L

Re: Offset Voltage data

Unread post by decipha »

No, why would you do that?

Use the actual numbers they give you.
efloth
Posts: 319
Joined: 2021 Feb 15, 22:12
Location: Sacramento CA
Vehicle Information: 1991 F150 4.9L J1X 80lb Injectors E85
1995 F150 5.8L MOB1

Re: Offset Voltage data

Unread post by efloth »

decipha wrote: 2021 Jul 21, 19:42 it matches perfectly

.8722 is for the high slope only

The offset gets multiplied by .6306
That's what you are telling me .6306 is low slope

EDIT: offcomp not low slope. I'm with you now. Thanks for the help guys.
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