Dbeluscak

Okay, that sounds like a silly problem to have, but it’s a problem. Here’s what’s up.. most of you followed along with us here https://www.chevyhhr.net/forums/hhr-...erboard-54048/

I’m still waiting for HP Tuners to properly improve the problems. I realize not seeing the tune doesn't help much. I also can't wait to get my wideband gauge installed and tune myself!

Because it’s still driving daily, I haven’t had the chance to send the DP out for ZZP to fix. Since I haven’t done that I haven’t got the replacement lower charge pipe, so I really can’t go over ¾ pedal. That being said, I realize, my knock sensors probably aren’t happy from the DP clunking the trans. And my intake charge is probably sub-par due to the lower charge/intercooler connection (no leaks though!)

I really don’t need more than ¾ pedal. The car will get 20-25lbs boost no problem. I’d rather be more in 22lb range because of the stock internals. The GEN3 block will hold up just fine, my HP will only be limited by the cast pistons/rods. The stage 3 turbo kit from ZZP included all bolt ons, with the tune and manual boost controller. I have MBC turned as low as it will go, wastegate spring pressure is set to 23.6lbs. I have checked with ZZP and insured my vacuum routing was correct. I never got a straight answer from ZZP on what my boost levels should be, if I go WOT I’ve seen the gauge peg itself at 30lbs. Way too much!

The real trouble is I can’t seem to hold much boost, ever! As soon as it spools, the wastegate will flutter and all is lost. Regardless of where my foot is on the pedal. Even while gently taking off from a light at 1/4 pedal. I’ll hit 5-10lbs and without lifting my foot, the wastegate opens. I’m really not sure if this is normal for this setup or not. I doubt it..

Now when I let off normally; the wastegate flutters and then the BOV opens, no problem.

Assumptions to follow; any knowledge here would be greatly appreciated.


I would assume that the larger turbo is making more air than desired at any given RPM. Since the turbo is no longer ECM controlled, the last resort it has is adjusting the throttle body to compensate the extra air-load. I’ve seen it do this by watching live data from the scanner while the wife drives. Aside from cranking the DAL tables to 100% across the board I'm not sure I'll get around ECM compensation...

Any thoughts? I’d be curious to see how MississippiSunburst’s SS behaved before and after having someone work over the ZZP tune. If I can’t tune the air in, I think I want to adapt a cable-style throttle body. Not sure how it’d react; but I’d be willing to figure it out if it puts me back in control of the throttle body.

The pulses of large amounts of boost are just not cutting it. The car has plenty of power, but the wastegate should not be opening as much as it is. If I'm WOT into 4th gear the wastegate finally shuts and the car pulls like it should, unfortunately by that time we're well above the posted speed limits. This is what has led me to believe my DAL table is to blame, that and Drive By Wire (not a fan!)

DrLoch

Information, which waste gate and BOV are you using?

Do you have a schematic of some sort for all the vacuum lines?

When you were seeing the spikes to 30 PSI which sensor were you monitoring, the one in the charge pipe ahead of the throttle body or the one in the manifold?

I do not recommend that you change to a DBC TB. Changing to a DBW throttle body will no doubt freak the ECM out and who knows what will happen. It uses the DBW TB to control, idle RPM, traction control, stability control, and the biggest, torque management which what everything on the LNF ECM is based on. You exceed the torque management parameters and it reacts in some strange ways, as you are seeing. It is trying to protect the motor, you force it and you will no doubt be testing the integrity of the oil pan.

While the live scanner you have may show some of the parameters you want to see, it may not be showing you all the parameters you need to see at one time.

The DAL (Desired Air Load) and MALT (Max Air Load Torque) have to work in harmony. If they aren't as a final resort the ECM will close the TB, which you are seeing. That is it's only remaining means to control torque, close the TB which will reduce the calculated torque.

What puzzles me is that ZZP hasn't seen this before, or maybe they have... Based on your combo you can't be the only person that has seen this anomaly before. I have seen posts on the HPT board about this in the past, cant remember if was LNF related or not. There are a number of very smart people that post in the LNF section, but the first things they are going to ask for is a log and the tune before they will even try to help.

All that being said, you need to bite the bullet and get HPT and log that thing. That may not be what you wanted to hear and by no means am I an expert when dealing with the LNF ECM controls, you asked for input, that's my 2 cents.

I can assure you that I've had more than my fair share of breaking very expensive parts and that is not what you want to do. Your wife will not be happy with you if she can examine a connecting rod or a piston by rolling down the drivers window or following the oil trail coming out from the back of her car.

Dbeluscak

I'm using a 38mm TiAl wastegate and ZZP BOV. I'm only watching the boost gauge. Changing TB's is a last resort. It isn't favorable to override the ECM. I'm positive that I can tune it out, only a matter of time.

I dont have a schematic for vacuum but its pretty simple. The boost control solenoids are connected electrically, that's it. No vacuum going to them.
Basically its this;

Intake Vac Port -> BOV -> DONE
Lower Charge Port -> T's to the MBC input and Wastegate, then the MBC output goes to the top of the wastegate.

I'm sure ZZP has dealt with this before. In fact, I'm hoping Mississippi Sunburst chimes in because we have the same Turbo 3 upgrade. Only difference is my block is Gen3. He said his car was much happier after someone over at CSS tuned it. I can wait for HPT, it will probably be the wifes Christmas present (if I can get away with it..lol) The car isnt going to get hurt, not being abused (yet). The plan is to garage it over the winter while I complete the Catch Can, Downpipe, and Lower charge pipe, some painting, on and on. Not to mention I have the 08 LT to spruce up with her old Gen2 motor!

So its my understanding that the Pro version of HPT is useless for the LNF because we cant use the Outputs or the Black box for Datalogging...any truth to this?

Thanks for your 2 cents sir, invaluable information here. At least I had the right idea, I cant wait to start tuning. I do some killer tuning with Electric motors and variable frequency drives, our largest machine has 16 motors @ 250HP a piece. Capable of generating 13.5 million ft/lbs of torque. Trying to get all that synced up is a lot of head scratching. No where near the same, but both put a smile on my face!

Danby

DrLoch

As far as what version of HPT to get. You are correct our motors use a wide band O2 sensor to control programmed lambda output. So with regards to the LNF you don't need the pro version, but, if you are going to use HPT to re-program anything else you are going to wish you did have the pro version, like I found out. I bought the std version and then up graded to the pro version. While piping the WB signal through another connection into the ECM does work in some cases it's a major PITA.

I believe it cost me $250 to upgrade to pro, so I spent 499 for the std version and 250 to upgrade... while the price for the pro version is 649.... I have some other things I want to monitor hence the need for the Analog I/O. BTW I just looked, the upgrade is now 289 plus shipping. If I were you I would be very very nice to your better half and persuade her to get the pro version. Tell her your worth it.

With regards to tuning and synchronizing multiple 250 HP drives... I know all about that, I'm a systems integrator. I'm electrical and mechanical, I do and/or have done electric drives, hydraulic integration with proportional valve, servo valve, etc. I have also designed and built some very elaborate test stands for the automotive industry as well as the military. So I am quite familiar with what you are doing. I believe you mentioned that you are involved with tunnel boring, do you work for Robbins? If so I may designed some systems that were used on one of your machines when I was working for another company.

Dbeluscak

Woah! What are the odds...small world. Yes, I work for Robbins and love every minute. I'm an electrical tech so I get to build and test machines all over the world. Do you know what project you were engineering for? Regardless, that's awesome.

In regards to HPT, I was planning on the full version anyway. I read there somewhere about a workaround for the LNF. I have no fear of electrical PITAs, sounds like fun trying to make it do what I want. As long as I'm tuning by spring I'll be happy. The SS, isn't going to get out much this winter. Bought her a "winter" HHR last week, 07 LT that jumped time and had a minor collision with the intake valves. Bent 3 but I'm going to swap them all with the 2.0 valves I had lying around.

The intention was to sell it come springtime. Now my mom saw it and HAS to have it. It's sunburst orange so she called dibs. There goes my profit! It will be cool taking grandma with us to the car shows, now we'll need 3 spaces.

Dbeluscak

So ZZP has failed me yet again. I have no idea why I didn't just Google my wastegate earlier. I guess I ASSumed ZZP knows how to plumb a MBC. Since the SS is still down I'm trying to line up all the work I've got left. Having too much boost is a major concern, since the wife wants to go racing.

Looked up the correct plumbing from Tial. I had a T on the IN side of the MBC that went to the bottom of the wastegate. The OUT of the MBC was tied to the top port. This was all wrong.

Well, I could never hold any boost and it comes on too strong. Turns out the wastegate wasn't able to do it job. Following the manufactures setup is probably a better bet. I'll be replumbing with my MBC tied only the the bottom port. The top is open, vent to air.

I only wish it was warmer! At least I have a few months to finish all the mods. I've got big plans for my LT,it will take the SS's place in the spring. More on that later!

JerseyJames

NEVER too much boost!!!

DrLoch

Are you using an electronic boost controller or a manual setup?

Dbeluscak

Manual for now. I'll go electric once I get all my other headaches hammered out. The only way to approach a custom vehicle...1 headache at a time

@James- it's great until you boost a hole through a cast piston. Been there, done that! We'll remain cast as long as everything holds out. Pistons are my only HP limiting factor. Everything else should hold 30lbs no problem

DrLoch

A vehicle that is too custom for anything to fit/work.



Know all about that. LT1 with a 24X conversion to a LS controller, than add some boost to complicate matters.