Z06 running stupid rich, Vortech SQ supercharged

[natels1]

We have a 2004 Zo6 running a Vortech SQ Trim supercharger system with gaseous intercooling.

It is running 5 - 6 lbs. boost
When it was dynoed it hit 428WHP at below 10.1 AFR... it was off the chart so I dont know the exact number. It smells like gas and blows black smoke, so its purrty fat. Before now all of our tuning was done by sending out the program, having it edited and sent back. Now we will try to do this ourselves.

We have 42lb injectors, and the Fuel pressure is at 60 PSI. The injector rated fuel pressure is, as I was told, 90 PSI.

Stoich AFR is set to 14.57

Right now the the PE table is as follows -

0 = 1.203
400 = 1.203
800 = 1.203
1200 = 1.197
1600 = 1.192
2000 = 1.226
2400 = 1.226
2800 = 1.218
3200 = 1.229
3600 = 1.229
4000 = 1.254
4400 = 1.277
4800 = 1.294
5200 = 1.292
5600 = 1.292
6000 = 1.292
6400 = 1.292
6800 = 1.292
7200 = 1.292

Injector Flow Rate vs. KPA VAC -

0 = 39.44
5 = 39.62
10= 39.81
15 = 39.99
20 = 40.18
25 = 40.30
30 = 40.49
35 = 40.68
40 = 40.86
45 = 41.05
50 = 41.23
55 = 41.36
60 = 41.54
65 = 41.73
70 = 41.85
75 = 42.04
80 = 42.23

I plugged our numbers in to a Spreadsheet on RedHardSupras site, and it wanted us to change the IFR table and put lower numbers than what is above, ranging from 34.29 - 35.31. I found that odd it was lower than 42, but I tried it anyways. Well it smelled like a boat and the O2's were reading 1200!! so I put that back to normal.

Any ideas on how to get the PE AFR to around 12.8 ?? While cruising around we get about 27 MPG on the highway closed loop.. it runs pretty good. Not sure if I should mess with the VE table or not.. or if I have something set wrong with the injectors since they are larger and the fuel pressure is at 60 PSI not 90 PSI.

Any thoughts?

BTW I dont have the .bin saved on this computer that's why I had to type the numbers in. When I get home I will fix it so you can actually see the file itself.

[30thta436]

What 42lb injectors are they? I don't know of any injectors that are flow tested at 90 PSI. Their are 3 types of 42lb injectors I know of. SVO, Bosch, and Delphi. The SVO injectors are flow tested at 39.5 PSI. The Bosch and Delphi are flow tested at 43.5 PSI.

What are your long term fuel trims doing? Your injector flow rate table looks a little low. If you are rich in the PE mode and in closed loop then I would look at correcting your injector flow rate table. Are your ltft's really rich as in really - .

[natels1]

I was thinking the 90 PSI thing was off. Im not sure what injectors they are to be honest, I didn't put them in.

Ill use 40 PSI as a base and tune from there. Thanks!

[slow]

I would first datalog and see what "commanded air fuel ratio" is.

Based on simple math, and I hope i do this correct, as the gm stuff is backwards from my normal thinking.

stoich /PE = commanded 14.64/1.29 = 11.34

I would get the commanded air fuel to be what you are requesting, then adjust the other parameters to get the fuel correct.

Ryan

[redhardsupra]

what 42# injectors do you have? if they're svo42s, then at 60psi their config should be:
49.32736833 49.6245747 49.92001164 50.21371037 50.50570123 50.79601367 51.08467629 51.37171692 51.65716259 51.9410396 52.22337353 52.50418926 52.78351104 53.06136245 53.33776648 53.6127455 53.88632135

if they're something else, then you gotta figure out their data and insert proper numbers into the spreadsheet.

i don't know how you got your numbers, but that would be a reason to run rich.
Marcin

[natels1]

Bosch Injectors. The car was running way rich before I changed anything, I dont know why the person who was doing the calibrations before didn't have the right information.

I plugged in pretty similar numbers to the ones you posted RedHardSupra, and she runs a lot better now. Unfortunately I haven't been able to log any data with the new settings, which bothers me truthfully because I have no idea what's going on.

The person in charge is not me, and he seems to believe the car is fine just from taking it home for the night. So if it blows up before we get it on the dyno to tune it next week its not on me :

[natels1]

Another question... before I get this thing strapped to the dyno and tune it.. what do you think my commanded AFR should be (PE)? right now it is 13 flat straight across, but maybe it should get richer as the boost rises, so start at 13 and maybe drop to 12.5 or something?

I know I'll play with it on the dyno, but I was just wondering what a good base to start at would be. Ive haven't done any tuning until about 2 weeks ago, let alone a supercharged car, so some guideline would be very much appreciated.

[tici]

You talk about "gaseous intercooling": is it a Blowerworks kit (Carrol Superchargers)? He uses this name, that's why I ask.
For tuning he told me to go this way:
use water alone and low timing (for this level of boost 13 -15).
Adjust AFR 12.8 - 13.0
Use 50% ethanol instead of water (for this level of boost about 4-8 GPH)
AFR will change but don't bother (goes rich)
increase timing until power remains constant
run the lowest timing with max power (dyno)
If it pings try increasing the alcohol % and / or GPH liquid.
Mine is set this way and works fine: 5PSI boost, AFR with water 12.7, 6GPH 50% ethanol, 17* WOT timing.

FOr the rest: where are your LTFT? If 0 +/- 4 it's ok.
Have you disabled the COT? You should, at least for tuning or the car may run RICH.

[natels1]

yes it is a blower works kit. Thanks for the advice/info!!

[brianw21]

See my recent post on forced induction tuning. Walks you through doing a good tune.