Hey guys, I've had HPT for a couple years now and have really just used it to load tunes in and change very minor stuff. I bought the wife a '09 Cobalt SS/TC and would like to do some basic tuning right now before I get it dyno tuned next spring. I was wondering what are some basic fields that are a "must" for starting with the LNF (i.e. more boost!)? thanks
Last edited by SS#8788; 05-26-2009 at 10:32 PM.
max airload torque table - increase values above 2500rpm to 99%, keeping a slight taper down to ~ 90% at redline for turbo longevity (my preference, some run 99% to redline). Log after this, if you see abundant knock, DECREASE the value in the PE lambda table, this richens the mixture (lambda * 14.68 = commanded AFR). I keep it above 13:1 in the 90% load column, and no richer than 12.5:1 in the 100% column.
Thats the basics. If you want more boost, you can increase values in the desired airload table. If you still want more after that, you'll have to research cam and spark timing or consider hardware upgrades
2013 Cruze Eco - CAI, Catless DP, Catless MP, ZZP FMIC, Ported Intake Manifold, Mild tune (17psi), best 43.5mpg, 175ftlbs (pid)
2008 Solstice GXP - ZFR 6758, catless, AEM stage 1 water/methanol injection, Hahn Racecraft Intercooler, solo street race cat back, LE5 throttle body - 307whp on a dyno dynamics (stock turbo numbers), 100 octane EFR6758 numbers - 463whp/454wtq
cool, thanks. anyone else with more inputs?
I was reading into the DALs and was wondering how do you know how much to increase them by, just a couple at a time and go test? I saw terminator was saying from 3k and 30% you can start to ramp it up, in another post. but how much is that, 5, 10 or ...? thanks in advance
I would multiply the last three columns (80, 90, 100% load) by a fixed amount, such as 1.05 (5%) or 1.08(8%) and then smooth the whole table two or three times. Log and add more if you are not yet happy.
The key is adding a little at a time in fixed increments so you can tell when its too much boost, and to keep everything smooth.
2013 Cruze Eco - CAI, Catless DP, Catless MP, ZZP FMIC, Ported Intake Manifold, Mild tune (17psi), best 43.5mpg, 175ftlbs (pid)
2008 Solstice GXP - ZFR 6758, catless, AEM stage 1 water/methanol injection, Hahn Racecraft Intercooler, solo street race cat back, LE5 throttle body - 307whp on a dyno dynamics (stock turbo numbers), 100 octane EFR6758 numbers - 463whp/454wtq
thanks alot, I'm going to mess with it more tonight. I'm doing a little and then go testing. I'm going to redo the DALs like you suggested. When I smooth, you said the whole table, including the 80%+ I changed, or just from 70 down?
The whole table
2013 Cruze Eco - CAI, Catless DP, Catless MP, ZZP FMIC, Ported Intake Manifold, Mild tune (17psi), best 43.5mpg, 175ftlbs (pid)
2008 Solstice GXP - ZFR 6758, catless, AEM stage 1 water/methanol injection, Hahn Racecraft Intercooler, solo street race cat back, LE5 throttle body - 307whp on a dyno dynamics (stock turbo numbers), 100 octane EFR6758 numbers - 463whp/454wtq
You can start ramping them up slowly from 2700-3000 and up and starting at 30% load just multiply by 1.04-1.05 down there then by 1.07-1.10 in the higher loads and rpms then smooth it and slowly increase from there until you get to the pressure level you want. Make sure you are commanding 99-100% in the max airload torque table from 2700 and up. That way you actually see the full airload you are inputing into your DALs. I have seen many post on various forums concerning the car holding only 20 - 21 psi even in the midrange even though there was 22.5 psi commanded, and 9 times out of ten it is because their max airload torque table was not maxed out from 3k to redline.Originally Posted by SS#8788
This may be slightly off topic, but I always wondered why the DAL table has the shape that it does. Why is there a higher airload requested at 400 rpm, and it ramps down as revs increase? The 100% load column goes from 263 @ 400rpm and ramps smoothly down to 204 @ 6320rpm.
Given the characteristics of the turbo and the whole system, it makes more sense to have the boost ramp up to peak @ about 3000 rpm, hold through 5500 rpm and drop off after that.
Is this some trickery to try to spool up the turbo if you floor it off the line (which I do not believe is good for it)?
2013 Cruze Eco - CAI, Catless DP, Catless MP, ZZP FMIC, Ported Intake Manifold, Mild tune (17psi), best 43.5mpg, 175ftlbs (pid)
2008 Solstice GXP - ZFR 6758, catless, AEM stage 1 water/methanol injection, Hahn Racecraft Intercooler, solo street race cat back, LE5 throttle body - 307whp on a dyno dynamics (stock turbo numbers), 100 octane EFR6758 numbers - 463whp/454wtq
Good thought.I too wonder the same thing I bet it will increase driveability some if you decrease those less than 2000 rpms and high load DALs some it would take some of the strain off the turbo and the engine would be choked down less IMHO. I think I will try lowering the DALs some in the lower RPMs and high loads.
I redid the DALs like you suggested. In the other post you made about DALs to someone else, you said they should be around 250 in the 80%+ range? I'm looking at ~180-190 in the 80%, ~210 in the 90% and ~230 in the 100%. I'm about to go load this and go test. If i'm not seeing what I want, I can come back and multiply them by a little more, correct? My max airload torque is 99.9% too.
2002 Camaro SS - 556whp
2009 Cobalt SS/TC - ???whp
My DAL
As for why the stock table ramps up at the end - it does that for all loads. I think partially it's because it's an electronic throttle body. So, if your right foot is not giving it enough, it'll try to prevent a stall at lower RPMs.
Last edited by SSpdDmon; 05-30-2009 at 01:28 PM.
2013 Mustang GT
ok, so why did you change it by a set number compared to a percentage and why didn't you smooth it? I was also wondering, the % field is the load, is that like the throttle %, or am I way off?
2002 Camaro SS - 556whp
2009 Cobalt SS/TC - ???whp
The percent rows across the top are throttle position if I read it right. If you alter left of the 50% columns, it'll start to affect the way your car peforms in normal, daily driving scenarios. About 50% throttle is where you'll start to get into boost. As for why I did what I did, I only wanted to affect the heavy throttle stuff. So, I made the 90% column somewhat similar to what was in the 100% column stock and then upped the 100% column to where it's at for max boost. This helped because then I copied what was in the 100% column of the stock PE table over to the 90% column and set the 100% column to where I wanted it.
Last edited by SSpdDmon; 05-30-2009 at 04:38 PM.
2013 Mustang GT
Man... I am still having trouble with my DAL's... I am maxing at 312 in the 100% column, and still only seeing 20 psi. The max airload torque tables are set to 100% in all fields, so I know thats not the issue. I do see a very steady 20 psi, and am not really getting any compressor surge or anything.
Any more ideas? Should I keep raising them til I see what I want to see? I am seeing more in my MAF lbs through every increase i make though... so I know I am getting more air, I am just not seeing the increases in boost.
Dont worry about an increase in boost, as long as the lbs/min is going up you're flowing more air and that's what counts.
Well, when do I stop then? I mean, can I max the turbo out if I am not pushing more boost? I really don't wanna mess anything up, but the extra air is nice.
Every time i take the DAL's up, I add fuel to make it safe, so i know thats good. But I just don't wanna ruin the turbo.
Is your boost gauge in the car reading 20psi or is your scanner logging only 20psi too? What rpm range is it sitting at 20psi? mine spikes to 23-24 psi or split second then falls to 21-22 psi then to 19 or so at 6700 rpms. Turbo runs out of steam up there.
I'm running 20psi pretty consistently, maybe 21 peak. But I only have the Dejon SRI and spring. I plan on adding a 3" turbo-back in the near future. When I get that, will that free up a couple pounds of boost?
Last edited by SS#8788; 05-31-2009 at 09:29 PM.
2002 Camaro SS - 556whp
2009 Cobalt SS/TC - ???whp
SS#8788,
At what RPM cell do you have 312 in the DAL table? In my opinion, the cells in the 90 and 100 % column below 2000 rpm are kind of meaningless - you are "usually" not going to floor it at 800rpm right? That's what I was alluding to before.
If you don't mind uploading a tune file, we can make suggestions to get you running where you how you want to.
2013 Cruze Eco - CAI, Catless DP, Catless MP, ZZP FMIC, Ported Intake Manifold, Mild tune (17psi), best 43.5mpg, 175ftlbs (pid)
2008 Solstice GXP - ZFR 6758, catless, AEM stage 1 water/methanol injection, Hahn Racecraft Intercooler, solo street race cat back, LE5 throttle body - 307whp on a dyno dynamics (stock turbo numbers), 100 octane EFR6758 numbers - 463whp/454wtq
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