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Discussion Starter #1
I figured I'd break this out into it's own thread.

First, I can confirm that the current HP Tuners beta software works GREAT with my 2012 Impala LT. I can't comment on your results, but mine are wonderful. Both the editing and scanning software work perfectly for me.

Next, my observations while scanning the car. Using HPT's VCM Scanner software, I noticed a couple of things with the factory tune:
- The car has quite a bit of KR (knock retard) right from the factory.
- The car is quite obviously choked with severe torque management.
- Digging deeper into the KR, I found that my car was running quite lean based on reported fuel trims.

I started tuning by removing a bunch of torque management and messing with shift points a bit. Specifically, the following changes were very beneficial:
- Disabled 'Tip In' torque management in 1st gear
- Disabled 'Fast Torque' torque managment
- Removed 'Brake Torque' limit at 0 MPH
- Added considerable amounts of torque to 'Driver Demand' tables (ABOVE 4% TPS, doing this at 0% TPS = run away car)
- Changed ETC table to allow 100% throttle position at any RPM
- Raised WOT shift points in gears 1-4 to 6700 RPM
- Raised downshift speeds 2 MPH for gears 4-1 above 50% TPS
- Raise upshift speeds 2 MPH for gears 1-4 above 50%

The car way woke up! No more 'dead spot' from a stop in first- it shreds tire now with TCS off.

I then looked at the KR and lean fuel trims and made a few more changes:
- Added 3% fuel to the MAF curve above idle
- Threw 2* of added spark into it between 1000 and 3000 RPM (to help it feel 'snappier' - note that the KR I've been logging has been coming in above 3000 RPM)

I've still got a bit to go- I may lower PE fueling enable mode as it currently won't enter PE until 90% TPS at most RPMs. I might change the trans shift properties a bit too (to speed up the time taken by shifts). Not sure yet.

It's a HUGE improvement over stock. I'll probably leave it as-is for a bit as the weather isn't cooperating with me. When the weather clears up, I'll get it really dialed in.
 

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Back in Black
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Glad to see that you are getting some positive results. That bog out of the hole sucks at times, did that also fix the bog going around a turn and getting back on the gas as well.
Weather should be better this weekend so you can play some more. Your somewhere around Pittsburg?
 

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Glad to hear that you're having positive results tuning your 2012 Impala.:beer:
 

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Discussion Starter #4
Thanks guys!

That bog out of the hole sucks at times, did that also fix the bog going around a turn and getting back on the gas as well.
For the most part, yes...unless the car is in the middle of a shift during the turn. If it's in manual shift mode, there's no bog anywhere anymore. The gas pedal is very responsive now. I actually might turn it back a bit- I'm spinning tire a bit too easily at this point.

Weather should be better this weekend so you can play some more. Your somewhere around Pittsburg?
Yep, just East of Pittsburgh! Hopefully this weather clears up, if not, spring is almost here.
 

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I noticed if car is in manual mode my gas mileage is actually better mainly because I stay in the sweet spot works much better on the turns because you are in the right gear. Just wish that the paddle were in a fixed place instead of moving with the wheel.
Have to check on a mod come spring.
 

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Discussion Starter #6
Weather was nice here today...or at least nice enough for more tuning.

It's basically dialed in now. The car is an ANIMAL compared to how it was with the stock tune. It's overall tons more responsive and fun to drive.

I played with the shift tables a bit more to enable easier downshifting, sync'd PE enable with driver demand torque managment, added a splash of fuel to PE mode, got the MAF dialed in, and disabled 'Fast Exit' torque management.

The car is nasty now (for what it is). I'll probably track it in the spring. If it doesn't go 13.something I'd be shocked.
 

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Discussion Starter #9
Sent my file to 08boo...if others with HPT read this and want to share info, please post up.
 

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Just got done with the upload. I have my winter wheels on right now (stock 17's) and it is a different car. It will BURN the front tires off. I did everything to my file that is listed except I added some rpms to idle cutoff while in park or neutral. I have a magnaflow catback on (SS V8 model) it and it sounds great. The maganflow backhalf will fit, just cut the stock off after the third converter (which I hollowed out) and install. Fills out the rear valance perfectly.
 

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Discussion Starter #11
Awesome- great to hear your results are as good as mine! Thanks for the exhaust information too.

I really hope that these cars gain a big performance following...I kind of see this as the next GTP type ride. This 3.6L is a damn potent mill, and with HPT support I think there's a TON of potential.

I can't wait to get some ETs with mine. I think it's going to shock a lot of people. Tracks around here open in April.
 
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Apex Everything
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I'm glad somebody's finally tuning the 3.6 motors, sounds like a big improvement. It makes me wish I didn't have the 3.5L/4 speed even more
 

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Discussion Starter #13
I can't stop driving it. I guess in the summer when my Mustang is back on the road I'll give the Impala a break, but right now the urge to grab the keys and go for a spin (or 20) is overwhelming.

Even with the stock exhaust on it, allowing the engine to actually rev a bit has made the exhaust note quite nice. The car is a blast to drive right now.
 

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I'd like to see a dyno of a stock 3.6 Vs. your tune. It sounds like the mid range torque would be much-improved.
 

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This is a lot of info, I'm a novice and want to go step by step! What unit did you buy from HP Tuners and what are the final specs you modified to?
 

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This is a lot of info, I'm a novice and want to go step by step! What unit did you buy from HP Tuners and what are the final specs you modified to?
This is not a novice mod, you are changing parameters in the cars pcm and tcm, you need to know what you are doing or you can really mess your car up. Might want to look online and read up before placing an order for 500 dollars for a HP tuner. But then again you got to start somewhere. :eek:k3::eek:k3:

by the way Welcome
 

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Discussion Starter #17
Just a quick update- I turned 'Torque Shaping' back. The gas pedal just a little too 'twitchy' with it off, and I ended up chirping tire accidentily a few times.

With it back on, the pedal got to dull again, so I added more torque to the 'Driver Demand Torque' tables.

The pedal is now very responsive still, but smoother then my previous tune.

MRidall- I could send you a file to work off of. I'd read some HPT 'how to' guides and get an idea of what you'll be doing before ordering. If you have a pretty good grasp of how engines run/mechanics you'll be OK, if not, I'd probably not get into tuning with HPT right off the bat.

Maybe I'll make a guide to tuning with HPT for this platform....
 

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Discussion Starter #18
Another observation- there seems to be a 'dead spot' in the factory gas pedal assembly.

I can literally slowly apply the gas pedal in small increments and watch the TPS % gauge in HPT not change at all, until it all of a sudden begins reading quickly.

This has been an issue with all sorts of other ETC cars (including my Mustang). It can't be addressed with tuning, as the pedal assembly literally contains 'dead space' between the electronic contacts when the pedal is applied.

The solution with my Mustang (and other cars with this issue) is to shim the gas pedal so that the dead space is taken up. This can be a tricky proposition. I may look into doing this to my Impala.

I'm also noticing some annoyance when slightly hitting the gas from a 20-40 MPH roll- the car seems to stumble a bit at first, then start moving when I apply a little more gas. I think this is caused by the remaining negative torque numbers in the 'Driver Demand' torque tables. I'm going to tune these out and see if the issue persists.
 

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how long have you had your HP tuner?
 

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very interesting. keep us posted

I have thought about playing with mine but im not sure how the trans will live..
 
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