I have a 1995 Corvette LT1 383 with LongTubes and LT4 hotcam. I have all software and hardware required to tune and have began doing so. So far i have switched to speed density to begin tuning the ve tables. At first it ran really rich 108 blm LTFT after lower the ve tables i have got it to come up to 115 but after running for awhile it went back to 108. Looking for some advice?
i can probably help you if you show me your bin
also you should just rough out your VE and then throw a maf back on there..
i just viewed your log. your coolant temp sensor in the waterpump is **screwed** (or the wiring)
that needs to be resolved before anything will line up in your tune
it keeps jumping from closed loop to open loop, then it throws a code and defaults to -40c which certainly will screw your trims (and much more)
Yes I noticed those whacky coolant temp sensor readings and i wasnt sure if it was an indication of failure or if it was pertaining to forcing the car into speed density mode. I will inspect and try to resolve this.
Here is my .bin
P.s. THANKS for the quick reply steveo, I have closely studied your work involving the EE mask and tuning the LT1.
you'll need to pretty much go back to the start once you've fixed the sensor, but that's ok, since it doesn't seem you've tuned much yet.I will inspect and try to resolve this.
Understood.
After I get back to square one I am unsure of what i should be changing first. Should it be closed TPS timing? The spark table in general? or Scaling the VE table?
I have resolved the coolant temp sensor issue. I flashed to a stock .bin and adjusted the cylinder volume. After switching to CL the BLM quickly headed to 108.
Here is the scan and the bin
decreased the VE tables for the idling range by 20%. This scan is alot longer, as i was able to drive around a little bit. Also it runs really rough around 1500-2000 rpm. Timing maybe? it pulls around 41* @50-60kpa.
Last edited by johnny_b; 05-16-2015 at 02:57 PM.
does it have high and low octane tables like ls1 ecu and default to low octane table while maf unplugged ??
it's going to run rough until you get your VE tables dialed in, which takes a little while to work out, but it could be timing too. you could try dropping 3 degrees or so from the affected areas and see if it gets better.
i'd highly reccommend (in my XDF which i hope you're using) doubling the values in 'o2 int delay - airflow' to account for the increased o2 distance of your longtubes, and reduce 'CORRCL airflow%' by about 20% so the o2 sensors aren't fighting with your cam. it'll really clean up closed loop stability at low airflows. i'd also set 'o2 swing voltage' to 450mv in all cells. it does want a hair more fuel at idle, it'll help.
you will need way more than a couple of parking lot maneuvers and idling to adjust your ve tables properly. you need a ton of logs, generally exported as flat data so you can paste stuff into a spreadsheet so you can run averages. thing is, as you drive it around, it should self-adjust to a point. the amount of those adjustments are how you can ballpark your VE table.
there's actually an old tool called 've master' that works with datamaster EE logs, you might feed it a fairly long driving log just so it can ballpark your VE tables for you as a starting point.
for idle, you should set your closed tps spark advance to 28 degrees from 0 to 1200 rpm. right now it drops off below 800, the drop in advance decreases rpm further. maybe turn your idle speed up slightly so it idles better for you until you figure your VE tables out.
are you eventually going to put a maf back on this thing or are you dead set on running speed density?
are you running stock injectors? stock fuel pressure? stock stall?
if you just unplug the maf, yes. if you set the speed density enable bit, no.Originally Posted by delcowizzid
Yes I am using your XDF. I will adjust these setting closed loop settings that you have mentioned. I will turn up the idle table and the spark advance.
I am using VE Master to help dial in my tables.
I plan on going back to MAF. I was only running speed density to get my VE tables dialed in since my engine has had lots of changes.
Injectors, Fuel Pressure are both stock. The stall I'm unsure, but id guess stock or close too it.
At what point should I go back to the MAF tune??
Last edited by johnny_b; 05-16-2015 at 06:18 PM.
Steveo,
I have changed the O2 sensor settings exactly as you indicated. Raised the idle and the closed tps spark to 28*.
I have also lowered the spark table in some areas, the "running rough" in the 1500-2000rpm range has decreased but did not disappear.
The fuel trim has gotten a lot better, and I can tell the car is driving better.
Here is the latest Datamaster file, as well as the .bin used to generate it.
Also here is a change log for the bin:
Edit Log for JB '95 Corvette v1.0.bin created by TunerPro.
************************************************** ************************
05/16/2015 02:43:18 Scalar: Cylinder Volume changed from 717.25 ml/Cyl (0x50) to 780.01 ml/Cyl (0x57).
05/16/2015 02:43:24 Flag: Speed Density Enable changed from Not Set to Set..
05/16/2015 02:44:46 Table: * Idle Speed Target RPM changed.
05/16/2015 02:45:30 Table: * Idle Speed Error Timing Correction changed.
05/16/2015 02:47:08 Table: * Closed TPS Spark Advance changed.
05/16/2015 04:44:47 Table: * VE Table - Primary (400-2000RPM) changed.
05/16/2015 04:49:25 Table: * VE Table - Primary (400-2000RPM) changed.
05/16/2015 04:54:38 Table: * VE Table - Primary (400-2000RPM) changed.
05/16/2015 06:49:47 Table: * VE Table - Primary (400-2000RPM) changed.
05/16/2015 06:59:08 Table: * Main Spark Advance (400-4000RPM) changed.
05/16/2015 07:03:01 Table: * Idle Speed Error Timing Correction changed.
05/16/2015 07:31:36 Table: * Main Spark Advance (400-4000RPM) changed.
05/16/2015 07:58:09 Table: * Main Spark Advance (400-4000RPM) changed.
05/16/2015 10:12:52 Table: O2 INT Delay - Airflow changed.
05/16/2015 10:13:36 Table: CORRCL Airflow% changed.
05/16/2015 10:14:18 Table: O2 Swing Voltage changed.
05/16/2015 10:14:55 Table: * Closed TPS Spark Advance changed.
05/16/2015 10:16:32 Table: * Idle Speed Target RPM changed.
glad its improving, i'll have a look at your log tonight! could you point out a particular area where the 'rough running' is really bad?
im working on this beta of a tool which will be able to adjust timing on the fly in cruise ranges, so you could find the rough spot, then screw around with timing advance (as a passenger while someone drives your car, of course), and when you find a sweet spot (if it even helps) you could snapshot it and then you'd know how much timing to add.
are you interested in testing it for me sometime? it's not working yet (the linux version is, im porting it to windows as we speak)
one thing i do notice is that you aren't even driving the car. you need a more diverse log to do any useful tuning.
your entire tune is a hair too lean for my liking, you should always shoot for 'slightly rich' and let the o2 sensors lean it out a bit, not the other way around.. the engine will be way more responsive and healthy that way.
this cam doesn't even really kick in until 1500rpm+ and you barely take it over 2000. i hope you have a tall enough torque converter for that cam.
regardless im sure that we can fix up that roughness.
are you eventually going to put a maf back in this car?
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