Anyone know about the SCR redline?

[RodKnock]

So I bought my RS recently, and it had one of these tuners in it. It uad some tunes preloaded and I really liked the 91 octane tune.

My problem is now that I updated the tuner. Since the update it says "product update required. programming is unrecognized for this vehicle". But I've called Superchips twice now, both times they just said to update it again, no luck.

Is there a way to down-date these? Or maybe send your tunes? Otherwise I'm going to tune it myself with HP tuners, just trying to figure it out before I shell out the cash to unlock the ECM in HPT.

I have searched, but the threads are really old and don't seem to answer my specific question

 

[skurtov]

So I bought my RS recently, and it had one of these tuners in it. It uad some tunes preloaded and I really liked the 91 octane tune.

My problem is now that I updated the tuner. Since the update it says "product update required. programming is unrecognized for this vehicle". But I've called Superchips twice now, both times they just said to update it again, no luck.

Is there a way to down-date these? Or maybe send your tunes? Otherwise I'm going to tune it myself with HP tuners, just trying to figure it out before I shell out the cash to unlock the ECM in HPT.

I have searched, but the threads are really old and don't seem to answer my specific question

I think the defacto standards for tunes in this day and age with the Sonic is BNR or Trifecta. Not a lot of people use HP Tuners because it's not worth the effort that someone else can do for you and knows the nuances of the engine.

 

[ScarabEpic22]

I think the defacto standards for tunes in this day and age with the Sonic is BNR or Trifecta. Not a lot of people use HP Tuners because it's not worth the effort that someone else can do for you and knows the nuances of the engine.

It's the difference between buying the end product (a BNR tune) and buying the tool to create the end product (EFILive/HPTuners). Some people want to do it themselves, others want to buy a finished product. The missing piece here is the knowledge and time spent researching/optimizing the tune. This is the critical piece and why many people simply purchase a tune instead of build their own. (Trifecta uses their own, proprietary platform to my knowledge.)

BNR may sell you a (base) tune you can load and adjust with HPTuners, that'd be a question to discuss with them.

For the SCR stuff, I'm not familiar with it so you'd have to keep working with Superchips to sort it out.

 

[RodKnock]

So I went with HP Tuners (had a buddy with more experience with GMs help out). Played with turbo tables, torque limiting and driver demand, lowered thermostat for safety, and richened the power enrichment.

Pulls like hell at full throttle now, but I get a tiny bit of KR at some spots. First pull was bad, about 3-4*. Since then I see about 1-2* but it pulls butter smooth by the butt dyno and ear. RPM graph also showed a butter smooth delivery, no hiccups.

Is a tiny bit of knock retard normal? I know these ECMs are different than the older stuff I work on normally, so is it maybe supposed to retard itself a bit? I only have about 5* of timing in the top end.

 

[Italianjoe1]

Yes they are quite sensitive but the tiny turbo also gets hot easy. I tuned my Sonic with HPT right after I got it (I've been tuning since my Cobalt days so it was only $100 to unlock and tune myself), and I was a little surprised how easily it trips the knock detection but most of it is real. There is a tiny bit of false knock and if you are only seeing 1-2 degrees it won't hurt anything. Safest way to tell is to back the timing down that amount and if you fix it, it's actually knocking, either adjust the tune or leave the timing lowered. The way these newer torque based PCMs do thier thing though you can end up with slightly more boost because of less timing and still get knock, gotta be careful to log it accurately and make sure you are getting the desired changes. That's one reason I zero out a lot of the adder tables and get the timing where I want it while setting up my boost maps, then revert them back if needed. A properly built base timing table works just fine, we aren't tuning the car to run in every possible condition like the OEM calibration designers are.

 

[dtbrown]

When I asked Jerry at BNR about KR this is what he said.

"KR can vary, it's not something to be concerned with if its not constant and over 6*. A couple degree burst here and there is normal, that's how the engine manages ignition."

So I went with HP Tuners (had a buddy with more experience with GMs help out). Played with turbo tables, torque limiting and driver demand, lowered thermostat for safety, and richened the power enrichment.

Pulls like hell at full throttle now, but I get a tiny bit of KR at some spots. First pull was bad, about 3-4*. Since then I see about 1-2* but it pulls butter smooth by the butt dyno and ear. RPM graph also showed a butter smooth delivery, no hiccups.

Is a tiny bit of knock retard normal? I know these ECMs are different than the older stuff I work on normally, so is it maybe supposed to retard itself a bit? I only have about 5* of timing in the top end.

 

[RodKnock]

This is very helpful guys thank you. I'm not seeing anywhere near 6* after the first pull and I'm using my SCR to watch ignition timing (not useless after all, eh?). I'm staying on the high octane table and it's still smooth pulling after about 200km and a few pulls.

I don't have access to HP Tuners for about 2 weeks, but it's only driveability stuff I can think of for now, this little turbo is definitely maxed and I don't want to touch fuel or timing until I get a wideband.