devilfish

Hi all

In the works of puttin on the edelbrock TPI intake .
1991 vette 730 ecm.
Planing to swap out those stock multecs to Bosh III #24 from southbay Fuel Injectors.


https://www.southbayfuelinjectors.co...fuel-injectors

Im doing some dektive work now, so I know what to change in the 730 code.

I stumbled across this thread here, where Rbob talked about Offset Compensation etc.

I wounder if this info Rbob posted is also vaild for my planed #24 injectors, and the 730:

quote:

"
Fuel Pressure: 44 psi
Flow rate: 20.5 #/hr
Minimum PW @ 44 psi: 904 usec


Offset Compensation versus Battery Voltage:
6.4 Volts: 3264 usec
8.0 Volts: 1965 usec
9.6 Volts: 1386 usec
11.2 Volts: 1051 usec
12.8 Volts: 811 usec
14.4 Volts: 646 usec
15.0 Volts: 586 usec
Put zero's in this table:
Short PW Compensation versus Pulse Width:
0.015 msec: -162 usec
0.244 msec: -143 usec
0.488 msec: -122 usec
0.732 msec: -102 usec
0.976 msec: -81 usec
1.220 msec: -61 usec
1.460 msec: -40 usec
1.708 msec: -19 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."


Thanks for your feedback .

Regards
Anders

RBob

iTrader: (1)

The above data is for a different injector. I don't know how close or how far the values are from the injectors you are using.

RBob.

TylerSteez

iTrader: (3)

Wish I could tune, I have the 19lb bosch III's from southbay and after installing them, it doesn't run quite right. the thread you pulled that quote from has been on my mind a lot lately as the cause

devilfish

Thanks..

Back to the drawing board I guess.
Or just re-use my old multecs, whas nothing wrong with them, just thought about doing a litte upgrade.
I know from experince that try to tune without those numbers can be a pita.

Regards

RBob

iTrader: (1)

Since you have a tune that works, all is not lost. I've done the following along with others. It does depend upon having a good tune to start. And only changing the injectors.

Data log with the new injectors. Adjust the BIN flow rate to get the BLM somewhat centered at 128.

The next step is to work the injector offset PW compensation to get the BLM even closer to 128.

RBob.

The_Punisher454

What is the Bosch part number for your design III injectors you want to run?
it is located on the side, it will be;
0-280-155-xxx

We might be able to just look them up.

devilfish

True RBob, I just tried to cut some corners , if anyone perhaps hade those offset numbers