255 limit NOT present on 2009 Cobalt SS?

[GTPprix]

The GMPP flash has always been editable, this thread is about the stock 2009 LNF OS.

[Chris@HPTuners]

the limit looks higher on 07 & 08 as well.

[GTPprix]

Interesting, now find COT so I can shut it off for banzai pulls hehehe

[BennyHHR]

Just my limited input...

I've only tuned 1 ea. of '08 and '09 Cobalt LNFs. When comparing the stock cals, I noticed that the GM OS cal# differed, yet a HPT compare show NO differences. Anyone seen this??

[GTPprix]

HPT can compare almost anything

[rommer]

From a previous post I made...

"I did a compare of a stock 2008 HHR SS file and GM Stage 1 file and the first thing I noticed is that The HPT software is only looking at 69 of 114 parameters. Of the 69 it looks at there are only 15 differences with 54 similarities.

I'm guessing there are a lot more than 15 parameters that have changed.

I wonder if the 2 sensors and harness are available without buying the entire kit."

So I found a lot more no "No" differences Benny.

[sky888]

CHRIS/BILL, do you think I need to buy the GM Stage 2 kit that includes 3 bar sensors, in order to to exceed the 255kpa by using HPtuners and download the beta that Chris will soon develop?


or with this new 512kpa discovery, will I just need my HPtuner and wait for the beta that will later be developed, and just purchase 3 bar sensors (without buying the gm stage 2 kit)? so I can boost around 25-26psi without worrying about the limp mode?


In other words, do I need this GM Stage 2 kit or not to boost higher?

thanks!

[XXL]

CHRIS/BILL, do you think I need to buy the GM Stage 2 kit that includes 3 bar sensors, in order to to exceed the 255kpa by using HPtuners and download the beta that Chris will soon develop?


or with this new 512kpa discovery, will I just need my HPtuner and wait for the beta that will later be developed, and just purchase 3 bar sensors (without buying the gm stage 2 kit)? so I can boost around 25-26psi without worrying about the limp mode?


In other words, do I need this GM Stage 2 kit or not to boost higher?

thanks!

The stock LNF sensors are 2.7 bar. The Stage kit includes 3 bar sensors. According to Bill Duncan, there is a necessary headroom on the sensors... but I'm not sure how much headroom is needed. If it's more than 0.15 bar (2.7 - 2.55), then yes, you'll want bigger sensors.

The limp mode comes in from several angles, however, not just blasting over the MAP sensor range... so more will be needed to avoid limp (see GTPprix's request above).

[sky888]

The stock LNF sensors are 2.7 bar. The Stage kit includes 3 bar sensors. According to Bill Duncan, there is a necessary headroom on the sensors... but I'm not sure how much headroom is needed. If it's more than 0.15 bar (2.7 - 2.55), then yes, you'll want bigger sensors.

The limp mode comes in from several angles, however, not just blasting over the MAP sensor range... so more will be needed to avoid limp (see GTPprix's request above).

yup, I know that the stock sensors are only 2.7 bar, and the stage 2 kit is 3 bar.

but I want to know if I need to pay $600++ for a couple of sensors and a re-flash tune (plus use my HPtuner and get the latest beta that chris will soon develop).........in order to boost higher without going into limp mode?

or I can just wait for the new beta that HPT is developing (512 kpa max for the ecm), and just buy a couple of aftermarket sensors (4 bar), to enjoy the power of my GT3076 turbo, and boost higher without worying about the limp mode?

[shabby]

I suggest you wait till Chris is finished with the code, he did mention he found the overboost part in the ecm.

[GTPprix]

I suggest you wait till Chris is finished with the code, he did mention he found the overboost part in the ecm.

Now if I could just get more than like 19 PSI at 6500 RPM LOL Lots o' volume but man it would be cool to hold 23 at redline hehe

[cobaltssoverbooster]

Now if I could just get more than like 19 PSI at 6500 RPM LOL Lots o' volume but man it would be cool to hold 23 at redline hehe

i think you should run 28 up to 7k way way way better!!!! btf i believe is doing a gt4088r to 34psi with additional fuel injection hahaha crazy mf!!

[shabby]

Now if I could just get more than like 19 PSI at 6500 RPM LOL Lots o' volume but man it would be cool to hold 23 at redline hehe

Im at 32lbs/min past 6000rpm at 18-19psi, i doubt our turbo can reach 23psi at that rpm. If it would it would probably be at a much lower efficiency, time to upgrade

[GTPprix]

Im at 32lbs/min past 6000rpm at 18-19psi, i doubt our turbo can reach 23psi at that rpm. If it would it would probably be at a much lower efficiency, time to upgrade

Agreed, with the cold temps assuming my MAF cal is pretty close I'm showing ~36 (just barely cresting 37 sometimes) lbs/min of air at the top of third at 19 PSI I'm just flat out of turbo LOL DOH!

[Baldturbofreak.com]

Ko4+'s show around 38lbs/min at those kpa's.
At the bottom is forum member Hiltu's CBSS with KO4+. I'm helping him reduce midrange compressor surge, and the occasional rich pop.
If we get overboost control, I belive he will have swallowed this turbo whole by 25psi. (~40.7lbs/min)

Antonio,
wait unil CHris is done with the next beta. Dont buy the GM kit right now.
If we get the overboost/underboost tables along with perhaps the MAP/TMAP constant + adder's the need for the gmpp kit will be nil. (at least for guys like us, IE big snails- Dont give a hoot about warrantee)

If we're given access to at least those, I already have MAP,TMAP and pigtails worked out for 350kpa. If I wanna do some surgery we can rock 4bar.


Cobalt overbooster- Yup Gt4094R feeding into a KO4+. Compound setup. INsta-torque, rediculous boost capability, reduced turbo wear,makes women &fanboi's faint at the sight of it, with just a small penalty(5-8%) in top end compared to a big single. THis is from the increase in TIP.

[sky888]

Antonio,
wait unil CHris is done with the next beta. Dont buy the GM kit right now.
If we get the overboost/underboost tables along with perhaps the MAP/TMAP constant + adder's the need for the gmpp kit will be nil. (at least for guys like us, IE big snails- Dont give a hoot about warrantee)

If we're given access to at least those, I already have MAP,TMAP and pigtails worked out for 350kpa. If I wanna do some surgery we can rock 4bar.
.

Yo rick, thanks!

with this plan of yours, do we still need to buy an aftermarket 4 bar sensors and ditch the 2.7 stock sensors?

[cobaltssoverbooster]

yea shabby i had the wrong turbo in mind haha i was thinking gt3076r since it was on my second screen haha our turbos are pinched up top it sucks. i was maping cams found some problems and moved toward turbo upgrade and clutch haha.

btf- going to be sick i want to see a pic of that beast just fabbed up in place going to be sick!!

[Baldturbofreak.com]

So lets see.

she understands
MAP 512kpa = 59.76psi
MAF 912 g/sec = 120lbs/hr 1200-1300hp pending on bsfc.
IFR At least = 122lbs/hr (Chris any ideas about max injector size?)
IFP 2800psi Im told. (Same here Chris)

It's going to be redonkulous!

[XXL]

MAP 512kpa = 59.76psi

Rats! I'm not going to be able to run 80psi like Rod Millen's Pike's Peak Tacoma.

[Baldturbofreak.com]

Good thing they make 1/2 studs for our motors that go from the head to the main caps...