B4005 Small Pulse Adjust How does GM create this table?

[onfire]

Red,

Here's the lastest 86lb low imp tune.

[SSpdDmon]

It's been a while since I tuned my SVO 42's, but I was getting stuck on the 1.8 ms PW as well. I was eventually able to get the commanded PW down to 1.5, but then I discovered that anything less than a 1.78ms PW and the injector wouldn't fire (AFR's in the 20's).

I ended up tweaking the tune so I would see no less than a 1.79ms PW and made my DFCO a bit more agressive.

I found this out tonight as well. I got the PW's down to 1.5mS and saw high teens and low twenties on the WB for decel. I bumped it back up to the mid 1.7's now and it's better. Going to target a 1.7ms PW and see what that does.

[redhardsupra]

http://www.picotech.com/auto/tutoria...injection.html

take a look at this. injector voltage and current graphed as a function of time on a working injector. this would give us the offset/open/close times, and probably gives us an idea on the shape of the IFR curve for the closing phase.
anyone's got a scope to try this out?

oh this is even better, they actually chop up the fueling stages just like I did, maybe I'm onto something here:
http://www.lindertech.com/newsletters/nwk7~03.pdf


and another one:
http://www.automotivetestsolutions.c...rWaveforms.htm

[Ira]

anyone's got a scope to try this out?

I have a scope and if anyone want's to show up at my place in West LA, we can have a look and post the results.

Ira

[redhardsupra]

can't you just hook it up to your car and see what the waveforms look like? it would be really nice to have few different kinds to compare, like lucas, ford/bosch, gm stockers, holly...

[redhardsupra]

Red,

Here's the lastest 86lb low imp tune.

do you have some 'official' data on the injectors? are they the racetronix ones or something else (rceng?)

[onfire]

http://www.racetronix.com/3105FM.html

[redhardsupra]

what fuel pressure do you run them at? do you have a manifold referenced regulator? does your fuel pressure drop off at higher boost/rpm?

[onfire]

48 base psi. Boost referenced only 1:1 . Twin Bosch 044's so there's zero fuel pressure drop...when I was running Mototron 60's I had the base pressure at 74psi ramping up to 91psi....the pumps are now laughing at a base pressure of 48...

[Chalky]

I found this out tonight as well. I got the PW's down to 1.5mS and saw high teens and low twenties on the WB for decel. I bumped it back up to the mid 1.7's now and it's better. Going to target a 1.7ms PW and see what that does.

Jeff:

Any update? For those of us running the SVO 30's, I wonder if another injector would not work better to address idle issues. Maybe something with lighter internal parts that would respond quicker to minimum IPW's.