Tuner Feed Back concerning MPG

[Yukon John]

This is for the guys on the fence with tuners and how your mileage may be affected.

I'm running the Diablo I Tune 2 with my own parameter modification to the base 93 Octane tune that includes AFM disable and speed limiter disable.

I filled the tank with 93 at COSTCO in Ft. Lauderdale this AM and drove round trip to Port St. Lucie, Fl ...about 100 miles North on the Turnpike. I was able to run an easy 85 with cruise control going up. We drove around 40 miles on surface streets in PSL witch on a Sunday afternoon was moderate traffic. We stopped 6 times looking at prospective water front homes with boating access to the ocean for our future home. We got on the Turnpike South Bound and traffic was heavy to moderate. I encountered several lines of drivers that like to ride 5~10 MPH below the posted limit of 70 side by side. Once I would get a clear shot to get ahead of a pack like this I would run into the triple digits briefly to put myself a mile ahead of the pack...yet stay behind the next pack ahead by a half to full mile....maintaining 80~85. I made this "WOT" maneuver 4~5 times.

After we got home to Ft. Lauderdale...I checked the trip MPG since the fill up this AM...23.3 MPG !!!

This truck is completely stock except for the Diablo. I turned over 4500 miles odometer on the way up so I feel it is completely broken in. I am very pleased with my Yukon's road trip manners...especially standing on it pulling from 65 to 115 quickly and smoothly to pull away from annoying congestion !!

Any of the good quality tuners out there that allow you to make custom modifications to your engine/transmission tune can duplicate these results on any 2015/2016 5.3/6.2 Tahoe or Yukon.

In summary...Don't be apprehensive that you will loose MPG efficiency by installing a Tune...just make sure you have a Good Radar Detector !!!

 

[chicagofan00]

Mind posting the modifications you made to the 93 tune?

 

[Yukon John]

Mind posting the modifications you made to the 93 tune?

Sure...on top of the 93 tune I modified parameters as follows:

Disabled speed limiter
Disabled AFM
In TCM I boosted all shift PSI 20%
In ECM I boosted Throttle 20%, Ignition 10% at part throttle, Ignition 20% at full throttle, Fuel Pressure 10% at part throttle, Fuel Pressure 20% at full throttle.
I DID NOT change shift points or change the rev limiter.

As I tip to those that need just a bit more acceleration in certain traffic situations...use "Tow Haul" mode. Combined with what I have done along with the 3:42 gearing it lets you extend the 1~2/2~3 shift a bit longer to move thru lanes of traffic and to position your self in the lane you prefer.

 

[chicagofan00]

Sure...on top of the 93 tune I modified parameters as follows:

Disabled speed limiter
Disabled AFM
In TCM I boosted all shift PSI 20%
In ECM I boosted Throttle 20%, Ignition 10% at part throttle, Ignition 20% at full throttle, Fuel Pressure 10% at part throttle, Fuel Pressure 20% at full throttle.
I DID NOT change shift points or change the rev limiter.

As I tip to those that need just a bit more acceleration in certain traffic situations...use "Tow Haul" mode. Combined with what I have done along with the 3:42 gearing it lets you extend the 1~2/2~3 shift a bit longer to move thru lanes of traffic and to position your self in the lane you prefer.

Thanks, I might try making some of those tweaks. I'm currently running the 87 octane tune since it is near impossible to find 93 octane here in Phoenix. I would imagine no matter the octane tune the changes you made would apply still and wouldn't be fuel type specific?

I've also really been contemplating getting a custom tune from Diablew since I've also put in an intake and done the Corsa exhaust...I'm thinking he could help tune it to really take advantage of those?

 

[Yukon John]

Be careful with the advanced ignition timing with 87 octane fuel. It may create a detonation condition that the ECM will read and force retarded ignition timing. If that happens it's possible that you end up with less over all performance than if you made no modification.

 

[chicagofan00]

Be careful with the advanced ignition timing with 87 octane fuel. It may create a detonation condition that the ECM will read and force retarded ignition timing. If that happens it's possible that you end up with less over all performance than if you made no modification.

Good to know. Thanks!

 

[LGSONE]

Diablew, can do a tune for 91 octane if that is available and I have to say I only run 93 octane with similar mods and I could not be happier with his tune. You can run logs in the intune, pull the file onto a computer and use diablo's software to see if you have knock retard. If you do... bad, turn back the advanced ignition and rerun logs... My speed shop here in town showed me a motor with a young kid just ignoring all the signs... cost him a 5k motor... It was a bit extreme but I'm betting a new DI 5.3 is at least that much..

LGSONE

 

[chicagofan00]

Diablew, can do a tune for 91 octane if that is available and I have to say I only run 93 octane with similar mods and I could not be happier with his tune. You can run logs in the intune, pull the file onto a computer and use diablo's software to see if you have knock retard. If you do... bad, turn back the advanced ignition and rerun logs... My speed shop here in town showed me a motor with a young kid just ignoring all the signs... cost him a 5k motor... It was a bit extreme but I'm betting a new DI 5.3 is at least that much..

LGSONE

Might end up getting a Diablew tune then if he can tune it for 91 instead of 93.

 

[Yukon John]

Might end up getting a Diablew tune then if he can tune it for 91 instead of 93.

That would be a smart way to go if 93 can't be had where you are. Running too much timing on low octane will either dial back the total timing via a knock sensor or worse...beat holes in the tops of the pistons due to pre ignition.

These new heads on the Direct Injection Motors are a complete re- design from the previous versions. That's one of the main reasons for the power/torque jump even on 87 octane. My experience with them is that they like a bit more total timing and the extra advance wants 93 to take advantage of it. Honestly though...in the real world it will be tough to feel the difference between 91 vs. 93...a custom tune for 91 will be strong.

 

[Flynnstone]

Thanks, I might try making some of those tweaks. I'm currently running the 87 octane tune since it is near impossible to find 93 octane here in Phoenix. I would imagine no matter the octane tune the changes you made would apply still and wouldn't be fuel type specific?

I've also really been contemplating getting a custom tune from Diablew since I've also put in an intake and done the Corsa exhaust...I'm thinking he could help tune it to really take advantage of those?

What are your impressions of the Diablo tune? I've been on the fence and also live in Phoenix. Is it really noticeable?