I have a 93 SD Z28 with a pcmforless tune currently to just get things in the ball park. I'm going to send this to them tomorrow as well.

Thanks in advance...

Oh and my general complaint is that the car is very rich IMO. No crazy smoking but after warm it will puff a bit which I believe is fuel. It is much richer on open loop. Notice how the o2's don't seem to switch much, is this normal?

http://www.fileden.com/files/2007/12...irst%20Run.csv

 

Oh yeah man you are running way rich at idle to 1800 rpm and are bottom'd out at 108 (lowest measurable BLM). What injectors are u running? Might wanna call Bryan again at PCMforless and send him your log as he can tweak your tune and send you a new chip.

 

I'm running stock Ls1 injectors for now and I actually Alvin did this chip. I let him know what injectors I was running and I noticed the he did adjust the flow rate per hour to about what these things would be in my Lt1. My Lt1 injectors were shot and 3 of them were stuck wide open spraying so my buddy let me borrow his ls1 injectors for the time being. I made a large log file today from cold start in the morning all the way through closed loop for like 5 minutes and then closed loop with a/c for like 5 minutes. Hopefully they can tweak here and there. Don't know if anyone noticed but from about 2,500rpm to around 4,000rpm I'm pulling up to 7 degrees retard with an average of about 3 degrees retard. The is a 12:1 DCR and 9:1 SCR motor so I'm thinking the advance in the tune may be a bit more than what the pump guess can handle. What do you think Dave? Thanks so much for your help on everything thus far...

 

I just emailed pcmforless with any issues. I'm very impressed with their ability to make large changes simply over mail to where the car actually can drive at this point.

Dave on an honest opinion do my logs indicate a car that you would feel safe driving? Would you put a brand new 383 or and motor for that motor through this tune right now?

 

Replied to your PM. Running rich aitn't gonna hurt too much other than plugs and maybe O2s (if for a while), unless you are washing your cylinders with gas and have gas in the oil (could damage your rings). Check my PM for some tips and let me know what you find.

 

Thanks alot Dave I got the pm...

 

Its probably running rich enough to do damage. At idle, the pulse widths are about 5.5mSec. Thats at least twice what you would normally expect to see. The long terms are pulling out the maximum of 15% of the normal fuel, and the short terms are pulling out another 32%. In effect, the PCM is pulling out almost 1/2 of the normal fuel, but you still have 5.5mSec pulse widths. Seems like the injector constant may be way off.

 

Ok man that's about all the convincing I need then. I'm not going to run it anymore. It currently has 60 miles on this tune and oil so to hell with ruining my fresh build. For the record though the torque is absolutely sick from 3,000rpm pulls...



Thanks to everyone who has commented thus far and please keep the advice coming on these logs if you feel you have an opinion. I was also told about the injector pulse from a friend as well.

 

Ok hey I looked at my tune in a program and the injector flow rate is set at 23.5 which is way high in my opinion. I'm using stock ls1 injectors (the 26lb set from 99-00) I know, I know they suck but my stocker were what trashed the other motor from fuel fouling and my friend had these for free to get my by and they should be fine as long as I don't spin it out above 5,000rpm which I haven't. Anyways from my calculations these flow roughly 20lbs on my stock lt1 3 bar system. Is that flow rate set to high in the tune do you think giving me richness all over? Please answer...

 

The flow rate is 22.5 #/Hr

(3/4)^0.5 = 0.866

0.866 x 26 = 22.5

I thought the 98/99's used 28# injectors? Not sure, but might want to check.

That's not enough of an error to cause the problem you are having.

 

Ok. I used to have an ls car. The 98 fbodies got 28's the 99-00's got 26's then 01-02 got 28's again. Well this sucks. I suppose I need to get my flash n burn module so I can start tweaking myself...