cobalt ss/sc lsj questions....help please

ok first off I am a hobby tuner not a professional. however I have successfully tuned several cars/ trucks. my questions are NOT about the tuning process itself, mainly engine management strategies. I have searched and searched and my questions are not being answered, maybe im not searching right, maybe I am.... either way any help would be appreciated. im just curious. I am not struggling in any part of the tuning process at this point. the concept is the same. the more details the better. thanks in advance. note. I have the latest and greatest non-beta version in both hp tuners and scanner.

1. in hp tuners, the open loop a/f table is coolant temp by another temp that says "none". my question is what is the vertical coolant value? why not coolant vs map like any any normal v8? seems usless

2. why are the values in the ve table 4 digits? is this for better resolution? usually ve is a percent. although greater than 100% is possible on paper in the higher rpm/ high load, or "boost" areas. still why is the lsj ve 4 digits?

3.why are there hardly any tables for lsj. ls1 has tons and tons of sometimes usless tables but still you have options. lsj has no throttle follower or cracker tables. I know there are others but thats off the top of my head. it just seems like the lsj is kinda a step child compared to other pcms.

4. I also noticed in my scanner seems to be off at times. I can log ltft on table, but will not show up on graph portion. stft work on both table and graph. also I noticed every once in a while after starting another log session that my histogram data will add on top of the previous recording session. I have to "x" the hist and restart for values to seem legit. I know most people that read this are going to want a log file and a tune file but im at work and don't have laptop. so if no one has had a similar experience im not too worried about posting log/tune im just probing around.

5. once again I know I did not post log/tune but I also have notice that I have set EVERY timing table including modifiers and multipliers to achieve a certain wot timing number. my logged timing numbers are about 3-4 deg higher than what im commanding. my theory is there are other tables that gm uses, but hp tuners did not incorporate this into their software. it is easy to fix there are plenty other areas to compensate I just would like to know if other people notice similar stuff.

6. there are other small weird things that happen that im forgetting right now, but it ALMOST seems like I had better luck w the beta versions. that does not seem right to me. I tend to chase "perfect" numbers which I know always makes me chase my tail but I cant help to always think I can just get it a little better you know.

sorry for the long post. hope someone can shed some light. thank you

Bump..... someone has to know

Quote:

---

Originally Posted by cobrataz28

ok first off I am a hobby tuner not a professional. however I have successfully tuned several cars/ trucks. my questions are NOT about the tuning process itself, mainly engine management strategies. I have searched and searched and my questions are not being answered, maybe im not searching right, maybe I am.... either way any help would be appreciated. im just curious. I am not struggling in any part of the tuning process at this point. the concept is the same. the more details the better. thanks in advance. note. I have the latest and greatest non-beta version in both hp tuners and scanner.

1. in hp tuners, the open loop a/f table is coolant temp by another temp that says "none". my question is what is the vertical coolant value? why not coolant vs map like any any normal v8? seems usless ive never touched it, but maybe someone else can chime in

2. why are the values in the ve table 4 digits? is this for better resolution? usually ve is a percent. although greater than 100% is possible on paper in the higher rpm/ high load, or "boost" areas. still why is the lsj ve 4 digits? im fairly sure its in grams of airmass. lsj is run primarily off of maf though, so dont forget about tuning it as well

3.why are there hardly any tables for lsj. ls1 has tons and tons of sometimes usless tables but still you have options. lsj has no throttle follower or cracker tables. I know there are others but thats off the top of my head. it just seems like the lsj is kinda a step child compared to other pcms.never tuned any others, but the 2.2 and v6's have even less tables from what ive heard

4. I also noticed in my scanner seems to be off at times. I can log ltft on table, but will not show up on graph portion. stft work on both table and graph. also I noticed every once in a while after starting another log session that my histogram data will add on top of the previous recording session. I have to "x" the hist and restart for values to seem legit. I know most people that read this are going to want a log file and a tune file but im at work and don't have laptop. so if no one has had a similar experience im not too worried about posting log/tune im just probing around.never seen such a thing. maybe you can load log file if you have access or someone else can chime in. maybe you need to create a new config. for histos and custom pids, you are gonna want to use "parameters" as opposed to "sensors". this is opposite of what it says on the scanner, but the lsj is not a v8 and it has 1 bank instead of 2. thats why sensors will not work as well for the most part because they are designed for 2 banks.

5. once again I know I did not post log/tune but I also have notice that I have set EVERY timing table including modifiers and multipliers to achieve a certain wot timing number. my logged timing numbers are about 3-4 deg higher than what im commanding. my theory is there are other tables that gm uses, but hp tuners did not incorporate this into their software. it is easy to fix there are plenty other areas to compensate I just would like to know if other people notice similar stuff. you can zero out the other timing tables (iat spark, the positive values, ect spark, and youll see what you are commanding.

6. there are other small weird things that happen that im forgetting right now, but it ALMOST seems like I had better luck w the beta versions. that does not seem right to me. I tend to chase "perfect" numbers which I know always makes me chase my tail but I cant help to always think I can just get it a little better you know.

sorry for the long post. hope someone can shed some light. thank you

---

hopefully that helps out a little

#3) ecotec ecu's only have X amount of space for data storage. they got the car to run really good off a minimum amount of ve/sd required tables and said well that's enough storage. so yes the ecu doesn't really have a ton of space left over for more tables or cool extras like programming for live efi tuning.

#4) if your having issues with the software the forum will not be able to help. you must save an info log and describe your problem to hpt through a technical assistance message. use the message center on your hpt account main page.
reporting issues and providing info logs is the only way all the issues will get fixed. If the issue you are seeing is designed that way for a reason then hpt will explain why right after they tell you that the issue is not actually a problem. (this has happened to me before a couple times so i know they will treat you right)

#5) as stated if you are trying to set a base requirement (not just for timing but all other tables) you must first make all the base tables the same if there are more than 1 base table.then secondly you must neutralize the multipliers/modifiers. if you dont do those two steps then you will for sure chase your tail around.
with the lsj i highly recommend making a complete tune using the highest octane gas you wish to run consistently. once complete and satisfied lower the entire timing table by 5*. now fill your tank wil the cheapest gas and remove and modify the timing as required for the bad gas. once done leave this advance setup only on the low octane table then copy and past your previous high octane table into the high octane spark table. this way there is a fall back when times get tough and you dont have time to fiddle with a completely redone tune. *Most people don't think that far in advance and leave them the same. If you do tune like that then disregard my safety message.)

thank you gm cobalt and overbooster for your replies, I know my post was lengthy. airflow makes sense to me too on the ve table, however ve by definition is an efficiency percent so the table title is misleading. it should be airmass vs rpm vs airflow in my opinion but I know it doesn't matter. tomato tamato. I was just curious. I left my open loop table alone too for now but there are benefits of an open loop table that is referenced by ect and map so once again I was just curious. good point about 2 banks vs 1. I thought about that as well but the only concern that I saw was if you had a hist set up w a bank avg. then it would avg "0" w bank 1 and who knows what would happen then. I corrected that and so far don't really have much trouble getting computer to do what I want. my issue w my skewed log only happened that one time, my laptop battery was low and it was extremely hot. (I also started another log on top of an existing log, this has never been a prob before but just something I noticed). no big deal really on the log part ill get past that. thanks again though. I understand there are different modifiers and multipliers and offsets but I went through those already. ive logged since then and I am unable to get log problem to occur again so im just going to blame that on that one time event and be done w it...... overbooster I am still having a hard time w your "pcm doesn't have a lot of room" comment. that may be true to some extent. however I know for sure there are other strategies that an lsj pcm controls that is unchangeable w hp tuners (that should be in my opinion). a big one for me is the throttle cracker/ follower and rolling idle tables. for example: if your cruising down the road and you see a stop light. I press in clutch and coast. the rpms will hang at about 2k rpm until you basically are at a stand still. EVERY car has similar strategy. some have etc some have cable and an iac. but the pcm is doing this on purpose. other vehicles I have tuned have numerous idle airflow and other airflow tables. it still seems that maybe since lsj is less popular and a little older that some things were left out. maybe someone thought they are un necessary who knows. I still appreciate your input. keep it coming