Just dont try it at redline for very long, ever see a turbo overspeed and G-out? If im not mistaken that is getting to the top of it's pressure map. You gotta give the little turbo some credit. For it's physical size it sure can move some lbs/min.
Lyndon, if the tables are written for a 3 bar map, is the t-map a 3bar?
Have any input on the Coding question above?
Last edited by Baldturbofreak.com; 02-18-2008 at 08:12 AM.
Patiently awaiting useful maps! Ready to tune some turbo fun.
I wonder if we are going to be in the upcoming public release?
Id like to go wild with RPM but Im beginning to fear for the connecting rods.
If they exit- stage left I might not be able to re-use the crank.
Anywho, not having the ETC spoil all my fun when the needle pushes north of 20 will be nice. I hate "runnin blind" with clamped MAP's.
Noone has any input on the Map sensor swappage? Or how and where the ADC value is turned into a MAP #?
mts here, adding my 2 cents as another waiting for boost control, rev limiter changes that work, and torque/power/throttle management removal.
Oh and a Blitz EBC i-d boost controller was one of the first mods I did. Been dealing with limps for quite some time.
No I am not privey to the inner workings here at HPT HQ....I am just a pawn in the ocean of ...Originally Posted by shabby
At any rate, yes...I have to use something else to get work done.
So add me to the list as well ... not gonna fork over the cash till there is access to the full suite ...
Also, where's my GM Mode 0x22 Extended PIDS!?!?!?!I need my AFR!
I beleive that the PCM Might possibly be dialing in more overlap flow in the cams to reduce the amount of torque I'm making.
I wish I could see what the camphase is to confirm this. I know the throttle will dial back a few % as you head up to redline.
But I believe that over time the PCM will slowly dial back the torque using the bumpsticks. I have formed this hyposthesis from the ever increasing discrepency between MAF and VE airflow, and a corresponding decrease in output (I have a boost controller so it cant reduce torque via boost)
Soooo from all that I have read about the bosch PCM it's focused on output torque. It doesnt make dramatic changes to reduce torque back to desired levels. It seems to start with boost, then throttle, then cam overlap. A few % here, a few % there and before you know it- soggy cornflakes.
So when the whole schpiele is unfolded, will there be a master torque limit? It seems like the small TM table is under use in the HHR's and I imagine all fwd cars, but not the soltices.
Could it be that bosch put a subsystem & tables for GM cal engineers to use to tweak to each platform, but the master OP system for the LNF package is hidden and unchanged?
Is this why the initial Def file showed up quickly and the rest of the goodies are soo buried that it has caused the year+ delay?
Sneaky bastards!lol
Here is an interesting one - as soon as I installed the IAT2 regulator, the ecu no longer pulled the throttle back.
I'll keep checking up on this thread. I play in the 4th Gen forum, but i'll be here pretty soon once I can get my "mini c6" (solstice gxp coupe).
Take your time. From what weve been told were not on the back burner. We're not even on a burner. We are wrapped in tin foil and tossed into the back of the fridge. With like 4-5 leftovers in front.
ROFLMAO, after a long day that made me crack a smile
It doesn't have to be perfect, it just needs to be done in two weeks...
A wise man once said "google it"
[QUOTE=Baldturbofreak.com]Soooo from all that I have read about the bosch PCM it's focused on output torque. It doesnt make dramatic changes to reduce torque back to desired levels. It seems to start with boost, then throttle, then cam overlap. A few % here, a few % there and before you know it- soggy cornflakes.
I am in a similar state as the Solstice/GXP users here as I have a 2.8 turbo alloytec with Bosch ME9, no direct injection; I have some ideas I would like to throw out for discussion...
The torque structure/cylinder air charge tables (not accessible) appear to have several checks in place to prevent modification, such as a limit of ~12 seconds of overboost or if expected cylinder charge is significantly different that actual. I am working on an approach to circumvent this that I have not seen attempted yet. If I begin to scale the MAF (by adjusting the MAF calibrations to appear to flow less air at a given voltage and also change injector constants to appear to flow less by same percentage) I can see that the output absolute load is fooled. This does nothing by itself, in fact the car still runs perfect, but no more power...Now, what if we combine this change with a modified signal from the intake boost sensor? This might foil the reference checks as the reduced apparent loads and reduced apparent boost pressure would not exceed limits in reference tables?
This is not the same as manual boost control. I am proposing to modify the output voltage of the existing pressure transducer, perhaps by inserting a fixed resistor? (unless the signal is PWM, which I have not confirmed). Comments? Out in left field?
we've already done it bud. I can show you how to build a 3.8V zener clamp for both pressure transducers. The IAT2/map and the actual intake manifolp MAP.
Thing is it sends the VE lbs/min wacky. In fact it maxes out, i believe in an effort to prevent engine damage.
It seems like a bandaid, since it causes unpredictable behaivior from time to time.
I just want it done right. The programming way. Too bad I majored in hardware instead of programming.
I like leftovers. I have till late this year or early next for the coupe to come out anyways so back to playing with big brother (that's the one with tables
Just a suggestion - the more you talkto the head kahuna, the more likely you'll be sitting in the corner on time out. Try cookies or hj's instead.
I would also prefer er to work through the software as it provides a higher level of control, but must electronic or mechanical interventions equal the wrong way? I probably have a lot of catching up to do to get to where you are currently in understanding what does not work, but I would like to learn a bit more by trying myself.
I would be interested in understanding the zener clamp method you mentioned. From what I can find on this it is discussed in relation to AC environments and restricts output on one phase to a maximum voltage. Would this result in a steady state signal from the pressure transducer as pressure exceeded the upper voltage limit of the zener clamp? I was thinking of an offset to the out put voltage, but still linear with pressure increases. If the vcm thinks pressure is steady when it is really still increasing, then it makes sense that the VEs would max out as the AFRs go much leaner than expected.
If we have some time to waste while waiting for software updates, how about passing the time scrutinizing our other options again.
Cheers
C
All our sensors are 0-5v dc. They are of either the reference variety or pulldown/pullup.
The MAp and MAf's are reference voltage based.
You use a 1K resistor in the Map sensor wire (there are 3, ground, 5v reference and sensor) coming back from the sensor. on the ther side of it you reverse Bias a 3.8V zener diode to ground. The resistor is to limit current and prevent the dissipation of too much power by the diode.(burnout) It's about $1 in parts. I reccommend making a pigtail and putting them on a piece of protoboard. Then make a mold in clay and pot it in epoxy.
It will allow anything up to rated voltage to pass thru unmolested. Anything above is shunted to ground so the PCM never sees more than 3.8V (+/- .1v)
When it stays above 23psi for long enough with the T-map clamped the VE lbs min goes from 45-47 to 68 and stays there flatlined. It does maintain AFR and KR resitance But over a long enough period of time it gets mad..
Clamp both and its flying blind above 20.5psi. I can only speculate on the cam timings role as we don't have a means of monitoring it, but I beleive it it's still looks at the MAF lbs/min + AFR/dutycycle and goes- hey WTF? I'm not fooled.
If you want to do a pressure offset you can use a voltage divider. Or just smack a 3bar MAP in there in place of the 2.5. Not a very good solution, IMO. Math will be incorrect.
Billdoe-I spent my whole life in the corner, Why change now?
Fact is we've been told it will be some time before we get revisited, whats wrong with a lighthearted joke about it?
Would I be happier if it were sooner than later? sure! Id also be happier if the were boobies on cable too. But Im not angry about it. lol
+1 for boobies on cable to pass the time
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