I'm finishing up a turbo kit on a 350tpi. Ive gon through the motions of the 749 swap. Im confused as to the bpc formula.

BPC = 730.75 * (VOL / RATE)

; VOL = Vol of 1 Cylinder in liters
; RATE = Injector flow in gms/sec
;
; gms/sec = (lbs/hr / 3600) * 453.6

the 4.3 and 5.7 are close in cyl displacment and it is my understanding that the 4.3 comes with 30#/hr injectors

by that math, a stock bin would have a value of 137, not the 89 that it has.

Im running 42# in this car and my numbers come out to 98.5, wouldnt this mean more pw than the stock value?

Or is the cyl number factored into the ecu's equation? Im using promgrammer.

I also noticed that the 42# are a pain to idle. Any min pw numbers and timing suggestions to help there would also be appreciated.

Sorry if this has been asked before I try to read archives best I can before posting.

Joel

 

My stock $58 bin had a value of 135 for BPC.... fyi

By my calcs, you should be running a BPC of 94

You'll probably need to adjust your VE tables, as well.

 

Off topic.......How did you make out with the IAC?

 

all of the bins I tried had a bpc of 89. Ive used tuner pro and promgrammer. Asfor IAC, i hooked t up according to the swap documentation.

 

Do you know where the bins you looked at came from? Could they have possibly been modified?

I checked a stock BBZB and AYBN and they both have a BPC of 130. For all EGR entries. These are turbo 4.3l bins.

RBob.

 

If you connected the IAC wires as stated in the $58 freq. ask question stickie......then you did not need to swap any wires.

When I grab bins from the internet, I usually do an MS-DOS fc /b (file compare) to get a feel how they differ in terms of code and data. It kind of forces you to look into things more.

I use a value of 99 for BPC for a 355ci with 42#/hr injectors.

 

I have bbzb bins from moates site and the diyefi ftp. I have downloaded all I can find and all show .089 in promgrammer and .0889 in tunerpro. I also got the bins from the speedtoys bort page, they are running 30# and both the stock bin he provides and the one they had running in the car have the values I have. WTF mate?

 

IAC works great now, thank YOU!!! LOL

I seem to recall mine would go all the way to zero, then back out as *parking steps* - the '749 doesn't, and that was what was throwing me off.

 

I think you got confused with the different ways that the BPC value is acalculated. I think some tools interpret the hex number differently.
Also, your initial post says 89 and not .89 so it confuses the issue even more.

 

The .0889 is not an actual BPC value. I have no idea what kind of math they use to create that value, or what that value represents. The BPC as calculated by the equation in the first post creates a decimal value. That value is what is to be used in the BPC vs EGR table. As far as I know the BPC is a unit less value.

If you use the 58RR_V14.ECU file it accepts and displays the actual BPC value.

RBob.

 

Thank you much. I just went to the table in the hex editor and it all makes sense. does tunercat use the .0xxvalue or the xx value? I know a lot of people use promgrammer, and I assumed it would display the values commonly used, but it displays the .089 instead of 130

 

Are you using the correct TDF for a $58 mask in TC?

 

didnt use tc, only used tunerpro and promgrammer

 

Then change ? to xdf & TP.
Lots of people use the wrong xdf or find one with an error.
The RR_v14.ecu on moates should be the most correct.
Just import it to TP.

 

FWIW, the writer of Promgrammer claims that the injector size term actually works in it, and actually somewhat went off when he noticed my modified BPC and non modified pulse width. He claimed to have either 55 or 60pph injectors running with just changing the injector constant and some minor programming.

I never did get a chance to really experiment with it, since I blew up the tranny right after I got mine running the first time I took it to the track and that turned into a 4L80e/9” ford swap that probably won’t be done till this spring.