Jennabear

At 11:1 compression ratio (DI or otherwise) the engine *cannot* efficiently run 87 octane under any circumstances. As a result, knock occurs (heard or unheard) and the ECM retards ignition timing both immediately and long term. The result is reduced fuel efficiency (sometimes as high as 3-4mpg) and considerably less power output than would be seen on 89 octane. You won't notice this power loss under light throttle though due to the ECM's method of controlling throttle angle... essentially, the throttle will be opened more for the same power output target on 87 as 89 so that it feels exactly the same to the driver. In terms of ignition timing, where 18-19 degrees of advance might be the target by GM under the factory tuning, on 87 octane, that timing drops to under 10 degrees of advance to prevent knock from occurring (in response to knock that has already occurred). Anybody that has dealt with ignition timing should see this as a very poor situation. The knock retard occurs early and quickly and then the lasting effects (octane scaler blending the high and low octane tables) will stay in effect for dozens of miles before decaying out. GM doesn't recommend any higher than 87 because they know that a) they will be vilified for doing so by consumer reports, motor trend, car and driver, etc and b) they know that people won't listen.

For those of you with 2014+, you should not be running anything less than 89 octane...

The guys have a list of things they would like to see within the instructions (ie. WOT, stop and go, 0-60). If something is missing within the log, they will let you know.

Cut out makes no difference in the tuning. So either way works. Sent from my fone.

Chris is correct, $599 for the AutoCal. You must have been looking at the V2 which is $899. Sent from my fone.

No problem. Shoot me a PM if you need further assistance.

AutoCal? Sent from my fone.

Go to a different dealer!

Had lifters replaced on my 2010 Denali. With a tune... Bottom line, depends on your dealer and how much of a stickler they want to be. But, they will also have to prove that the tune was the source of the problem.

So long as you return the vehicle to stock, you should have no issues. (Just had my 2013 Denali XL, lowered, TVS2300, meth kit into the dealer for a warranty issue with my shock absorber. No issues at all with the warranty.)

Should be up and running now! Sent from my fone.

There are three different ones to choose from, check out forums for your 2014 to see which one would be best. EFI Connection.com has one, off the top of our head.

Can be all in the same tune. Sent from my fone.

You are correct, you will need the tune and an alcohol sensor. You can switch between fuel, however, you should run at least 7 miles after each reset, for the computer to learn. I am not sure of the part number, I would have to check with the guys. Sent from my fone.

Your computer isn't telling your engine what to do with the extra air ;) Sent from my fone.

Thank you for the review Jason! Happy to hear you are enjoying your tune. You are absolutely correct, the guys do everything through email for a few reasons: -they receive hundreds of emails a day, on top of building tunes, shipping items, and inperson tunes, phone calls would put them very behind -phone calls does not leave any documentation: they are able to go back through emails to see what a customer requested, or other discussions pertinent to the process -they can't see what is going on through the phone: if a customer has major issues with the AutoCal process, they will remote into the computer to assess the situation. This is much quicker than trying to decipher what someone is seeing, through their explanations on the phone. More times than not, the customer has missed a step, and the guys can quickly diagnose when they log into their computer. -phone calls rarely take 5 mins: most customers will want to continue the conversation, once they have the guys ears, not realizing the backlog of customers in email. How is that fair to the guys who have been waiting for a response via email, that someone who calls, gets to go right to the front of the line?

Yes, that shouldn't be an issue.

With the 6.2L you should be running a minimum of 89oct, 91 preferred. With the 5.3L 89oct.

Like the guys have said, we have detailed instructions for our customers. The link and log in info, will be included in the AutoCal box. The guys also preconfigure the AutoCals now, so that is one less step for you to worry about. Yes, no tunes are on the AutoCal, everything is built specific to your vehicle.

The AutoCal itself? efilive.com has forums.

Correct, if you get another vehicle, you can purchase another license/tune for that new vehicle.

For your vehicle, the AutoCal will be needed and that is it. $599 includes both the AutoCal and tuning for the first vehicle. The AutoCal can tune up to 8 vehicles, when you purchase the licenses for the other vehicles. Yes, the AutoCal can tune you 2014, and includes both the ECM (engine) and TCM (transmission). The AutoCal is an EFILive product, which uses the full tuning software suite offered by EFILive. That being said, EFILive has access to many more tables than other tuning software suites out there, with HPTuners being it's closest competitor. There is a reason that many tuners won't tune for intakes/headers/FI and other mods- their software/experience does not allow for optimized access/changes to those tables. All our tunes are dyno developed and tested. With over 10,000 vehicles under our belts (over 4,000 hands on, inperson alone), both cars and trucks from mild to wild, safe to say, they are pretty dialed in. We do offer a discount to active duty military and LEOs.

Yes, with the AutoCal and scan cable tunes, all tunes are built based on the datalogs you send over. We send different octane tunes over. However, with the compression ratio of your 5.3L, you should be running a minimum of 89 for optimal results, even on the stock tune. Our tune updates are free.

Check your intake tube, may have come loose.

The process is this: -AutoCal is shipped to you -you configure the AutoCal for your vehicle and collect a datalog as well as stock tune -you email the datalog and stock tune to BBP -BBP will review datalog and let you know if anything is needed or if there are glaring mechanical issues -BBP will then build your tune and email your tune files to you -you will load the tune files to your AutoCal -you will use the AutoCal to flash the tune to your vehicle -you will collect another datalog and email to BBP -BBP will review the datalog to make sure all looks good Let me know if you have further questions!