Injector Battery offsets
 

Does anyone have injector offset compensation vs battery voltage tables for Bosch Design III #280-155-811 injectors?

I use Tuner Pro and their injector correction tables are 17 steps, 0 thru 25.5 volts.
Found a good price for them from E-bay - contacted the seller and he said that information was readily available on the net - haven't found any yet but that's no surprise.
I appears that no one has a good data base for battery voltage offsets from any injector manufacturer.
Be great to have but just finding the information is frustrating.

Re: Injector Battery offsets
 

This is the biggest problem with aftermarket injectors. I'm finding this out the hard way.

I'm seriously considering the Accel/Holley injectors. They are the Bosch EV1 style similar to stock, and they come with and publish the offsets. The offsets are listed right on their web site, etc.

Also the Bosch design III's are very LOUD. They tick and it's made worse because the TPI is bank fired and pulses 4 injector simultaneously making the noise sound a lot like an annoying lifter tick.

There are more characteristics about injectors than just the voltage offset also. Some of which are hard coded, ignored, or implied in the way the TPI was designed and coded. Thus using the EV1 style injector, which dates back to the late 70's and was pretty much what GM used for the TPI when it was designed, all that stuff the you can't easily modify in the code becomes a non issue.

GD

Re: Injector Battery offsets
 

You're not alone - several members have ran into the same problem.
I don't post often but this is the forum I follow most of the time.
I bought a set of 32# Bosch III injectors a few years ago from a vendor who later went out of business.
The injectors had the Bosch numbers removed but the vendor did supply the flow numbers - unfortunately little else.
I was just staring tuning at the time and I've learned quite a bit since then.
I have a "Saturday Nite Cruiser" so idle stability and drive-ability is important to me.
It's a shame that few injector manufactures provide much real useful data about their injectors and the internet vendors provide almost nothing.
Oh Well!

Re: Injector Battery offsets
 

I have blue top 24# hr ones from South Bay. I am still working on the tune however I think I have found the solution to the stumbling that I was having at 25-30 MPH at about 12-1300 RPM. It has been a process of elimination you might want to try the setting I have as a place to start. The Small PW correction was the key issue on mine. The
https://cimg2.ibsrv.net/gimg/www.thi...a3089e5f5e.png
https://cimg8.ibsrv.net/gimg/www.thi...9347e68865.png



This is what has worked for me if I 0 out the table it stumbles bad

For 0 volts use the 12.8 value

Re: Injector Battery offsets
 

This may be them. My understanding is that the 280-155-868 and the 280-155-811 are nearly the same injector. Can't hurt to try them:

Injector Data Sheet: 280-155-868 : LU34, 34 #/hr Skinny

Fuel Pressure: 44

Minimum PW @ 44 psi: 729 usec

Offset Compensation versus Battery Voltage:
6.4 Volts: 3105 usec
8.0 Volts: 2046 usec
9.6 Volts: 1521 usec
11.2 Volts: 1204 usec
12.8 Volts: 970 usec
14.4 Volts: 785 usec
15.0 Volts: 752 usec

Flow rate: 35.5 #/hr

Short PW Compensation versus Pulse Width:
0.015 msec: -192 usec
0.244 msec: -152 usec
0.488 msec: -109 usec
0.732 msec: -67 usec
0.976 msec: -24 usec
1.220 msec: 0 usec
1.460 msec: 0 usec
1.708 msec: 0 usec
1.950 msec: 0 usec
2.197 msec: 0 usec
2.440 msec: 0 usec
2.685 msec: 0 usec
2.929 msec: 0 usec
3.170 msec: 0 usec
3.410 msec: 0 usec
3.660 msec: 0 usec
3.900 msec: 0 usec

RBob.

Re: Injector Battery offsets
 

TPI is batch fire, all eight fire together. The '7165 & 7730 ECMs only have a single injector driver.

RBob.

Re: Injector Battery offsets
 

Interesting, that short PW table is adding quite a lot once at/under 1.2 msec PW. Which does make sense as the minimum PW at 44 psi fuel pressure is 1.07 msec.

RBob.