Rich Idle after injector upgrade

[sd99ss]

I know... another noob with a rich injector story.

99 Camaro SS M6 - Stock LS1
SLP Longtube headers and loudmouth exhaust
Racetronix 255LPH in-tank fuel pump & harness
DeatschWerks 60lb injectors 18U-01-0060-8
NGK TR6 plugs .035 gap
MSD plug wires
MTI Cold Air

I went with the DW injectors because they have tuning data (http://www.deatschwerks.com/images/s...a%2018u-60.xls), flow matched and more reasonably priced than some.

I was expecting that I could just load the data into the Flow Rate vs KPA, Offset vs Volts vs VAC, Short Pulse Limit, Short Pulse Adder, Min Injector Pulse, and Default Injector Pulse - and have it run fairly well with an otherwise stock tune on a stock engine? For some reason, it's dumping way too much gas, starting off ~3ms pulse width, which is about what my 26lb injectors did, despite changing all of the injector tables? Once it gets past open loop, it pulls up to 30% from both banks, getting down to just under 2ms pulse. I assume that it should be 1.5ms or less? What's keeping it so high?

newfi3.PNG

I don't have a WB yet, working on it.

The 60lb injectors are getting ready for the ProCharger. (;

Logs attached? What's the deal? I wouldn't expect to have to play with the VE or other air tables?

Thanks.

[5FDP]

Gotta re-tune the airflow tables for the larger injectors. The MAF and VE basically determine how much fuel to give it.

They always have to be adjusted.

[sd99ss]

Gotta re-tune the airflow tables for the larger injectors. The MAF and VE basically determine how much fuel to give it.

They always have to be adjusted.

Thanks 5FDP. Looks like I have some more reading to do, as I'm not understanding how the volume/mass of air would change as a result of larger injectors and stock air system. I did look at all of the tunes specific to my car in the repo. A few on them made minor tweaks to MAF Airflow vs Output Freq or in some cases large changes in Cranking VE vs MAF vs RPM, but Primary / Secondary VE were untouched - yet all of the injector tables had been changed. I've watch videos on injector change and I believe that they also only pointed to fuel tables. The VE tuning articles that I've read seem focused on refinement with a functional car versus the course level of correction that I seem to need. My car is drowning right now.

Suggestions on where I start? Can I simply scale the entire primary/secondary VE tables (up/down) by some percentage? Is there a rule of thumb based on the relative change in injector size? Does anyone have a sample tune file that I could use as a baseline?

Thanks.

[sd99ss]

I went ahead and scaled down the primary/secondary VE tables by 30%, then the cranking VE, then copied the MAF calibration tweaks from one of the repo tunes, then started trying to defeat DE, prime fuel, pulse correction, and anything else that looked like it might be adding fuel - with no results. (yes, I know... don't screw with stuff you don't really understand... ). I had also previously adjusted the Flow Rate Mult vs Volts, which I assume would scale flow rate - it did change the injector flow rate reported in the scanner, but didn't change the pulse width. I'm assuming (and maybe I'm wrong) that the pulse width is the key in knowing if I'm actually dumping more or less fuel into the cylinders, regardless of what the car thinks the flow rate or air mass is. Injectors are either open or closed, and flow at a static-ish rate based on fuel pressure and are only slightly affected by MAP? Right? My minimum pulse width is 0.729. How do I get my startup idle down from 2.5?