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I did go with the jam cam. I started it up and everything seems good. Idle is really rough at the moment though and I've been chasing my tail trying to get it smoothed out. Increasing the base rpm doesn't seem to do much, it still manages to idle at around 600 on average even though it's set at 1000. Increasing the airflow final minimum tables doesn't seem to help much either. I feel like I'm missing something to help get this sorted out. I've looked at idle cam tuning guides but they have different/more parameters than the Gto and the guides are never specific enough for my ECU.
Any tips or useful links? I really want to drive my car to work tomorrow morning and start logging data for the VE table but I'm worried about how it's gonna idle in traffic, not to mention I need to replace my battery so if it happens to stall multiple times then I might be stuck with a dead battery.
Yea, I would not drive it to work acting like that. No way. add some timing at idle. it'll increase the rpm. use your scanner to change it and see what it likes. Sometimes you gotta add alot of idle air. A gto I tuned not long ago wanted double the air that the factory numbers were. I'd set the idle at 850 to begin with. Idle tuning with a drive by wire car is a piece of cake. You have to pay attention to cells in the idle rpm area, higher and lower than your idle rpm...the fueling can not make a huge change from one rpm range to the next. 3-5 numbers at the most. Sometimes less...depends on if it surges or not. Follow the same idea with the timing at idle. You have to under a few things:

-large fuel swings from cell to cell is a no no
-large timing changes from cell to cell is a no no...its really sensitive with timing
-if you have too much timing at idle, you will get a dip in rpm as you stop..if may even stall. So basically if the rpm gets the highest with 25 degree, shoot for about 18 at idle and let teh over/under idle timing correct. its gives you timing leeway to catch a dip in idle....timing reacts faster than air
 

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Discussion Starter · #42 · (Edited)
Yea, I would not drive it to work acting like that. No way. add some timing at idle. it'll increase the rpm. use your scanner to change it and see what it likes. Sometimes you gotta add alot of idle air. A gto I tuned not long ago wanted double the air that the factory numbers were. I'd set the idle at 850 to begin with. Idle tuning with a drive by wire car is a piece of cake. You have to pay attention to cells in the idle rpm area, higher and lower than your idle rpm...the fueling can not make a huge change from one rpm range to the next. 3-5 numbers at the most. Sometimes less...depends on if it surges or not. Follow the same idea with the timing at idle. You have to under a few things:

-large fuel swings from cell to cell is a no no
-large timing changes from cell to cell is a no no...its really sensitive with timing
-if you have too much timing at idle, you will get a dip in rpm as you stop..if may even stall. So basically if the rpm gets the highest with 25 degree, shoot for about 18 at idle and let teh over/under idle timing correct. its gives you timing leeway to catch a dip in idle....timing reacts faster than air
Yeah, I went for a quick test drive around the block last night, and it kept on dying while coasting and sometimes when I stopped. Also, didn't want to start warm.
I just went and bought a Optima yellow top, it's nice having a job again. I figured a AGM battery well end up paying for itself the next time I leave an accessory powered on without driving the car for a week.
I noticed my dynamic airflow listed on the scanner during my drive was around 200lb at 1000 rpm and 180lb at 800rpm, seems a bit high compared to the suggestions you and someone else on another forum is giving me. I'm gonna give it a shot anyway and see what happens. Increased my base idle spark advance some along with coastdown idle spark advance, increased startup airflow under warmer coolant cells, decreased cranking ve, Reduced main ve in the idle/cruising cells that I hit during my drive yesterday and smoothed the table once. Gonna give it a shot and report back.
I tried posting the tune I'm about to try out but it won't let me attach it here, I'm posting it here in case anyone wants to take a peak.
HP forum Link here

Edit: uploaded the tune, it was much better than before, idle was really strong. I lowered the idle airflow quite a bit until spark advance correction went from high negatives to very low negatives. I set the idle at 800 and have been driving it around tuning the VE table. Idle almost perfect now, I still had an issue with warm starts, I added some more cranking airflow and I am waiting to see if that helps.
I'll post a log later in case there is anything I can improve upon.

Does anyone have any suggestions on how I should modify my spark tables (for cruising and wot) for a cam of this size?
 

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Discussion Starter · #43 ·
I'm still working on the VE table, there has been a lot of rain here lately which has been slowing me down.
My idle is pretty good and it's drivable but I know it can be better. I remember reading that when tuning idle with a cam to try and get the vacuum to be as high as possible. My vacuum is about -4.8psi at idle which is pretty low compared to before the cam, I'm guessing this is an indication of room to improve.

my most recent log file and tune are listed in the most recent post(#6) at this Link.
 

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Discussion Starter · #44 ·
I finally had a chance to start tuning WOT and was able to get all the way up to 6,000rpm. I didn't really think the cam would be that noticeable, I've already did some partial pulls in the past to around 4,000rpm and didn't think much about it, but during a full WOT pass, the cam must have woke up the engine and it was really surprising, it feels mean. I even pulled a few degrees of spark in advance for extra safety before hand.

Here is my spark table from my log, does anybody have any idea what a safe spark range may be for my setup at WOT? Looks like 14-15 is what I hit at max boost(so far).
509497

Some other variables like intake temp. might have pulled timing. I plan on finding a shop to do a dyno run when I'm done with everything.
Here is my spark table in hptuners, thanks.
509498
 
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