First log.....questions...

[spac3y]

Here is a spreadsheet of my logged values (2nd gear->3rd gear-cruise)

Excel Spreadsheet

I have a 1g/2g swap, 14b(@12psi), dsmlink, 450's,no fuel mods, stock boost....rest of mods are in the profile.

I'm not sure what to make of my log. From my log I think that my car is running rich (.98 @ wot), and that I'm maxing out my injectors (100% @ wot7k). My timing seems to be all over the place for the most part, but does flatten out @17deg @7kwot. My cruise timing is really really high - 30+ deg! My ltft is stuck at -12.5.

Calculated a/f ratio average for the log is off because I have the wrong settings in the program... @7k it calculates 9.07:1

? I had some boost leak issues that were fixed earlier today and since then I've drove 20min+ highway and 5+ idle. I've also noticed that I almost never show knock. Could my sensor be shot?

Let me know if this looks safe/ok/should I lean it out some?

 

[1LE]

Cruise timing is fine. I sit at 35 most times cruising. With such minimal mods and the LTFT at -12.5 it looks like you may still be kinda rich. However, the timing curve is just plain ugly. As if too rich in some areas and a little lean in others.

 

[spac3y]

Does my cruise o2 look ok? @wot I start off rich (.98) and my timing goes down till I'm really rich (1v), then I go back to rich (.98) and my timing starts climing up to peak at 18deg. Do you think it would be safe to adjust my global fuel settings, or should I adjust using the rpm based settings?

 

[1LE]

I'm not really sure the best way for you since I have a VPC/GCC and not a dsmlink. In general when tuning, you need to get the global so it's right most of the time, then fine tune with the rpm based adjustments. But, be careful to not let any one point get lean on you... IMHO, ignore the O2 sensor and tune by timing. Every car is different. MY O2 reads .85-.87 and I'm still a little on the rich side (if I don't stay a little rich, timing flatlines on the top. I think it's due to me still having a SMIC)

 

[spac3y]

I just did some more runs after finding out my injector dead time was way off I also leaned it out globally 7%.

Now... @wot
my o2's are down to .94v
my injector duty cycle is down to 94% peak
my new timing curve starts @ 18deg, goes down to 8.6 with one count of knock, and then climbs back up to 17deg at the end of 2nd gear.

And at idle my fuel trims are balancing eachother now.
At cruise my ltft is still -12.5, but I was only cruising for about 5 minutes. I'm going to take it out now and do some more.

And the final question. Do I have a bigger problem with my car, or is this where I should be? Should I go ahead and lean it out to .92v and see if my timing curve gets any better?

 

[1LE]

If you don't ever lean it out until the timing holds, you'll never know exactly where that point is That would be the hard part about tuning I have forged pistons so I don't get too concerned about a *little* knock. How much knock is "bad", I dunno... I just keep leaning the thing out until the timing holds, then undo the last thing I did Then, I finetune the the curve (usually holds a little at the top end, probly due to my 264/264 cams) Then I make a whole bunch of runs in a row like that to see if it stays happy (get everything nice and hot). After that, I usually find I have to add a little back in globally, I find that to keep it happy when hot, I'm 2% richer globally than it's happiest with when everythings at "normal" temps... YMMV, FWIW, you blow it up it's not my fault, etc. Good luck, take things in small steps, and be careful

 

[spac3y]

Well, I ended up running -5% globally, 0 idt, and from 3.5k on -5%

This seems to work pretty good. I hesitate to tune by knock as my sensor has never reported over one count so far and I'm not sure it's any good. (the back isn't mushy though..). Also since I can only tune by 2nd gear runs my ecu never actually gets to use the max airflow map, almost all my tuning is done on the mid airflow map. Oddly enough my timing curve fits the max airflow timing map perfectly. Just to make sure I'm not pushing it too hard I've been checking the plugs throughout the day and the don't show any signs of detonation. Also my egt gauge never goes above 1400degF @7k wot.

What is a good a/f ratio to tune for? right now at wot I'm getting about 10.95:1, however at cruise I get about 14.5-15:1 (calculated by dsmlink)

Should I have to pull as much fuel out as I have been? I know the 2g ecu runs rich, but does it really run THAT rich? I want to lean it out more so that my wot a/f ratio runs closer to stoich, but I guess I just don't have the balls right now

Heh...one more question.... Since I'm running the max airflow timing map that tops out @ 17deg should I try adding some?

Thanks for the help

 

[1LE]

Originally posted by spac3y
What is a good a/f ratio to tune for? right now at wot I'm getting about 10.95:1, however at cruise I get about 14.5-15:1 (calculated by dsmlink)

Should I have to pull as much fuel out as I have been? I know the 2g ecu runs rich, but does it really run THAT rich? I want to lean it out more so that my wot a/f ratio runs closer to stoich, but I guess I just don't have the balls right now

Heh...one more question.... Since I'm running the max airflow timing map that tops out @ 17deg should I try adding some?

Well, what I've heard is that 12.5:1 is a safe a/f to tune for. Supposedly you can go leaner, however that should leave you some margin for error. However, my concern is that since you're only tuning in 2nd, you may already be at 12.5:1 if you were in 4th... There's no substitute for some 3rd and 4th gear pulls. 3rd gear is probly good enough unless you're gonna use the car for trackdays. 2nd gear isn't good enough for much more than getting it close enough to try 3rd
2g's do run awful rich, I guess I'm not too shocked that you're at -5%, but I'd be very reluctant to take any more out than that without some higher gear pulls.
Adding more timing? I dunno. I'd be careful there. I kinda wonder how mine decides exactly where to max out. When the car is hot, it maxes at 17, but when the car is just warm, I've seen as high as 22 degrees timing advance at 7k... Must be some higher math thing goin' on in the ecu