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The Official HPtuners TBSS thread

54K views 200 replies 40 participants last post by  Bigtuna13 
#1 ·
As discussed with a couple of you, this is the start of a thread to discuss self tuning using HPtuners on the TBSS.

I know there are a few of us on here and this will give us a chance to compare notes and test theories.

My mods are on my signature. I am also running a LC-1 wideband and the enhanced I/O version of HPT.

I took a shot at it last fall and worked over my timing tables, reduced a little TM and had pretty decent results. Right now, I am starting over from scratch after running a ADM, Westers and Vector "canned tune" Just want to do it myself.

I have added a LS7 P&P TB on now and I think the AF needs a little work now.

So chime in !
 
#39 ·
92 is the best I can get.

But, if I get a bad tank of fuel or my MAF fails, I dont have anything to fall back on. I just dont know for sure what the criteria is to knock it into the lower table.

I guess I could set the low octane to about -5 degrees across the board so I would know when I hit it !!

There is sooo much stuff that can pull timing. I see HPT has some new PIDs for IAT timing reduction, etc. I just started logging ETC and TPS which could prove to be interesting.
 
#40 ·
It interpolates. When MAF fails it falls to low octane table and enters SD. Low octane is favored in the event that you have repetitive KR. You definately want to keep that in the event that you get bad gas. Especially with 10%eth blends. Water in the gas tank would separate the ethanol from the gasoline...
 
#47 ·
So you've got yours set up for Stoichiometric conditions at cruise, but 12.5 with throttle. Is there an AE table that you set to 12.5 or is there a tablet that references throttle position. Don't have HPtuners yet, so I'm trying to prepare.
 
#48 ·
Its kinda wierd. I dont understand what Chevy has done. They have their PE all over the place is if to compensate for a messed up MAF or VE table. I dont know.

I am going to reset my PE table flat and retune my MAF so commanded AFR matches actual AFR. See how that works for me.
 
#49 ·
That is what I had originally done with mine, but I was dialing in using LTFT's (NOT the correct method), and never got the wideband installed before going back to stock (the welder put the bung in the wrong place).

Be careful disabling DFCO and Trims when you are tuning with the stock Lingenfelter Hz values...they cause it to run VERY lean at idle and low throttle. At least, this was my experience.
 
#50 ·
Also make sure your voltage offsets and exhaust leaks are all in check or you will be seriously fuckin rich.. Set the wideband to report 10-18afr over 0-5v.. or an even smaller window if you still have problems there.

I have my tune all dialed in like you are trying to do. Well, I guess you could say I had my tune all dialed in. My wideband started acting up and I thought it was the change in gas quality from FL to CT. Part of it was, part of it wasn't.

They might have the PE table set like that because the MAF table is 'mathematically' pretty. This probably makes for smoother transitions in fueling. who knows. Just make sure you follow the same curve.. I usually compare my new file to stock and make sure everything is lookin good.. No peaks or valleys.. everything 'flows'.. I've also noticed big changes in the way the tune responds to adjustments to the cai tubing.. smallest thing and its all messed up.. So when you remove the airbox for misc maintenance.. remember that.
 
#51 ·
I am having a hard time staying out of PE trying to get through all the cells when tuning VE.

I was just thinking about changing PE tables to zero for the test. I would think a guy would want to make sure he is not going lean but seems like a logical way to run about 50 miles and propagate all the cells without getting some rich readings at the higher map cells??
 
#52 ·
Some people say the dead pedal spot is tuned out with a filter table correction to the .16g/sec cell, just bumping it a little in trial and error removed the lean/rich overshoot.

Personally, I have had good luck with reducing the transient fuel limit from 2048 to 1024 and reducing the delay to 30-40 pulses from the 56 or so.

I may try the correctin filter table method as well, but I'll be tuning by sotp instead of with a wideband.

Oh, and my PE is set to 2300 RPM from the superchips tune, with 85kpa setpoint. This keeps me out of PE unless I lean on teh gas. My normal cruise is around 53-60 kpa, so I have no worries about entering PE while cruise.

It's funny because the factory setting is 53 kpa and delay til 5000 RPM. Heck, I moved it to 2500 RPM just to see and I could tell under medium cruise accelleration it would feel like power rush once I hit 2500 RPM, now it's nice and smooth power and still gets good mileage (comparatively that is)
 
#55 ·
My bad, stock is 55 kpa on mine too. My current settings are:
MAP 85
MAP Hyst 3 (stock is 6)
Delay RPM 2300 (stock is 5000 RPM)
Enrichment rate .500 (stock is .200)
PE enable is 80 %TPS across the board.

The settings here are from the Superchips tune. They also modified the PE EQ ratio vs rpm table, but since I upgraded to 2.19beta, I can not open that table at all to see the differences.

So, I will probably end up reinstalling the 2.18 version. Looks like HPT screwed this beta up for the 2007 year.
 
#54 ·
My map pressure only changes with throttle change, if I'm at a steady cruise, could be 45 MPH or could be 80 MPH, map is between 53-60 kpa. If I even apply light accelleration it will go near 80 kpa, and a little heavier accel it goes way up to about 90-100 kpa, and the power is definite and smooth and positive.

With stock tuning, I almost have to lean on it to get any power, so I am happy that problem is gone, especially while getting better mileage.

The best part is not having to wait until 3500 RPM to feel power, I get it right off at any RPM.

I guess it's just a difference in all the items combined in the tune. I just wanted it to feel like a V8 instead of a turbo lagged 4 banger...if you know what I mean.

Oh, the transient changes got rid of the puff of smoke when revving up that all stock TBSS's do (thanks blaze for the tip). Must be a good thing, since it's like having too much accellerator pump shot and actually hurting power.
 
#56 ·
I have my pe delay set to 3600.. MAP 65....You will enter PE according to PE hot tps.. it is the *minimum* tps required to enter PE mode.. If you are running open loop you may just be seeing the rediculously rich stock OL values.. These are made even richer when A/C is on.
 
#58 ·
I have it set at that because of my stall speed. BTW: I temporarily disabled maf.. and wow.. car was 12:1 AFR at idle. well, idle-ish.. It could barely idle. I got it to idle at 14.5-14.7 in about 5 mins of tuning.. Could get it to stay at 14.7 with more time. Kinda nice.. but damn, it shifts like a mean-bitch... I wonder what tables don't work when in this mode. As in. PE/COT AFR Spark adder, adaptive idle airflow stuff too.. Idle was oscilating on coastdown like scary. I had to raise it to 1000rpm temporarily.
 
#59 ·
^^^ That's odd...mine didn't act like that at all when I ran in speed density. It did shift like it was trying to adjust my spine to look like the seat, but the idle was fairly smooth, and the AFR's stayed around 14.4-14.7. Mine was not tuned completely stock at this time, either, but I hadn't adjusted any fuel ratios...
 
#60 ·
Were you running open loop?.. Do you have a cam as well?
 
#61 ·
I think I was in closed loop at the time (don't remember for sure when I made the switch to ol). I am back to stock right now.

Never got the cam installed, though. And now it's for sale :(
 
#62 ·
I tried logging today. I am trying to tune VE and am confused :confused1:


In my attempt to get PURE air calibration I shut off fuel trims, locked it into open loop and zeroed out my PE table. I thought doing the latter would make it add zero fuel when it was calling for enrichment.

Its hard not to get into PE driving these things and I dont want to be leaning my VE tables to compensation for normal rich VE.

After logging my AFR looks like this.

It sure looks like PE !


 
#64 ·
Just use the filters to filter out cells that are in PE mode.. [sens.121]>13.5 or perhaps [pid.2112]<80 (thats etc is less than 80%)

Also, log AFR error and make sure you are logging afr commanded high res.. Plot the histogram values with 2 decimals and a min cell count of 50.. If its a small log, then.. lower. Smooth when viewing values under the highest precision.
 
#65 ·
Just use the filters to filter out cells that are in PE mode.. [sens.121]>13.5 or perhaps [pid.2112]<80 (thats etc is less than 80%)

Also, log AFR error and make sure you are logging afr commanded high res.. Plot the histogram values with 2 decimals and a min cell count of 50.. If its a small log, then.. lower. Smooth when viewing values under the highest precision.
You really dont have to filter them. Just "swipe over the cells up to a point and past into the ve table.

But there should be an easy way to inhibit PE??

I have AFR error logged too. Up top there is not much error.That is close to commanded AFR. I just expected commanded PE to be 14.7 with that PE table zeroed.

Did not know you could set decimals and I forgot about the min count last time. Normall have it set to 25.
 
#67 ·
Inhibit PE by setting the hot tables to 100%TPS, which you will never ever ever reach.

I still think turning off PE is the wrong way to tune.
I have been logging all morning. I ended up turning PE start point up to 7000 RPM. But the truck still drops 2% at heavy throttle. So the enrichment is coming from somewhere else.

Why do you think its the wrong way to tune? Keep in mind this is the start of a tune..

I am trying to set up the VE table so commanded = actual AFR. Stock PE comes in all over the place depending on load. I am just trying to rough in my basic AFR.

I am running a MAF that I have yet to find decent MAF/hz tables for. So I want to get it close without dealing with random PE.

I dont know for sure. This is just a test :)
 
#69 ·
Yeah, refer to Marcin's post on the hpt forums. As long as you are near 0% afr error, you are good to go. The extra enrichment may be coming from COT or something in the OL tables.
 
#70 ·
Well I am getting closer to little AFR error. Went out and logged today and made some VE adjustments and then did a brief scan.

One thing I am concerned about is I only did one WOT run and I am going lean for a brief moment on tip on. I had not let trims learn or anything yet. Gonna watch it.

Stock PE is 5000 RPM. I think I will bring that down just about cruise RPM.
 
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