Mpg On 6.2 Post-tune

tonygxp · June 15, 2010

My friend owns a performance shop here in toms river. I waited to get the tune until i was at 1k mi. So we dynoed the truck (yes, he has an AWD Mustang load bearing Dyno) baseline was like 308/325? after the tune it only picked up about 10hp/12tq. I wasn't impressed with the numbers but.... Driving it was the difference. Between the shift points, less torque management, advanced timing, etc. that he did really woke this truck up it's now an animal..

Now for the best part.. I traveled to New York a few weeks ago with 4 people. I set the cruise at 64mph and saw 18.1mpg there and on the way back i set it at 82mph and saw 15.6mpg. this was a 45mile stint on the garden state pkwy (very hilly/curves).

POST TUNE... same trip on the way up (running late) ran it at 82mph and saw 17.9 there. even with idling in Brooklyn's bumer to bumper traffic for hours it held 14.3, then after the ride back it was 15.1 (i have no doubt that it was running 17.9+ on the way back but i didn't reset the DIC to see what a solid mix would bring). Both pre and post tune were run using 93 octane from the same gas station, HESS. I also noticed a funny anomaly. for a while i slowed to about 76mph and watched the avg fuel economy slowly change to 17.6? I then reset the cruise for 82mph again and the mileage went back to 17.9-18.1??? i know that the cruise was leaned out a bit but i was amazed what a .2 a/f difference made in this thing. i think the 6spd gearing that the truck liked the little higher rpm, more torque at that speed? enough to overcome the small drag increase i guess?

anyway thought i'd share.. remember my Yukon is about 350lbs more than your pickups.

2005LT · June 15, 2010

Nice write-up Tony. I am waiting most impatiently for my BB tune Need that Autocal to come out already!

I am a bit surprised at the HP/TQ gains being that low but like you said, I guess it's all in how it shifts and advances timing. Don't know about yours but at low-mid throttle from a stop on mine (shifts occuring around 1900 or 2000rpm) this thing falls FLAT on it's face during the 2-3 upshift. It basically stops accelerating during and after the shift causing me to worry that someone is going to plow into my rear bumper. This has been remedied by a frustrated flogging of the gas pedal to get it moving.

coryf79 · June 15, 2010

My friend owns a performance shop here in toms river. I waited to get the tune until i was at 1k mi. So we dynoed the truck (yes, he has an AWD Mustang load bearing Dyno) baseline was like 308/325? after the tune it only picked up about 10hp/12tq. I wasn't impressed with the numbers but.... Driving it was the difference. Between the shift points, less torque management, advanced timing, etc. that he did really woke this truck up it's now an animal..

Now for the best part.. I traveled to New York a few weeks ago with 4 people. I set the cruise at 64mph and saw 18.1mpg there and on the way back i set it at 82mph and saw 15.6mpg. this was a 45mile stint on the garden state pkwy (very hilly/curves).

POST TUNE... same trip on the way up (running late) ran it at 82mph and saw 17.9 there. even with idling in Brooklyn's bumer to bumper traffic for hours it held 14.3, then after the ride back it was 15.1 (i have no doubt that it was running 17.9+ on the way back but i didn't reset the DIC to see what a solid mix would bring). Both pre and post tune were run using 93 octane from the same gas station, HESS. I also noticed a funny anomaly. for a while i slowed to about 76mph and watched the avg fuel economy slowly change to 17.6? I then reset the cruise for 82mph again and the mileage went back to 17.9-18.1??? i know that the cruise was leaned out a bit but i was amazed what a .2 a/f difference made in this thing. i think the 6spd gearing that the truck liked the little higher rpm, more torque at that speed? enough to overcome the small drag increase i guess?

anyway thought i'd share.. remember my Yukon is about 350lbs more than your pickups.

So you picked up 10hp/12ftlbs of tq TO THE TIRES... on an all wheel drive vehicle...... and you think that is a tiny amount.. and you are not satisfied?? If you had picked up 10hp to the crank, then i could understand your lack of satisfaction... .....

I can not tell you how much mine picked up from a tune, because i never dyno'd it... however i can tell you i picked up a full SECOND in the 1/4... and thats a lot for a 6500lb soap box....15.09@95mph stock 14.07@98mph HP tuned by me... Both runs had a K&N CAI...

Best thing is, this is an AWD Load bearing DYNO!!!

.

tonygxp · June 15, 2010

So you picked up 10hp/12ftlbs of tq TO THE TIRES... on an all wheel drive vehicle...... and you think that is a tiny amount.. and you are not satisfied?? If you had picked up 10hp to the crank, then i could understand your lack of satisfaction... .....
I can not tell you how much mine picked up from a tune, because i never dyno'd it... however i can tell you i picked up a full SECOND in the 1/4... and thats a lot for a 6500lb soap box....15.09@95mph stock 14.07@98mph HP tuned by me... Both runs had a K&N CAI...

Best thing is, this is an AWD Load bearing DYNO!!!

.

i hear ya. i was just thinking back to when my TBSS was dyno'd & Tuned. it picked up like 20hp/30tq. That was on the same dyno.

Nice write-up Tony. I am waiting most impatiently for my BB tune Need that Autocal to come out already!

I am a bit surprised at the HP/TQ gains being that low but like you said, I guess it's all in how it shifts and advances timing. Don't know about yours but at low-mid throttle from a stop on mine (shifts occuring around 1900 or 2000rpm) this thing falls FLAT on it's face during the 2-3 upshift. It basically stops accelerating during and after the shift causing me to worry that someone is going to plow into my rear bumper. This has been remedied by a frustrated flogging of the gas pedal to get it moving.

Thanks. And yes, mine was the same pre-tune, hated it. the tune done the right way will eliminate any sluggishness you describe, it did for me.

Stevens03 · June 15, 2010

I'm betting the 6.2 is tuned pretty well for 400hp at the crank. With that said, most of what you feel most likely comes from the changes in TQ managment making it feel like you have 400hp.

Congrats on the tune,...

coryf79 · June 16, 2010

I'm betting the 6.2 is tuned pretty well for 400hp at the crank. With that said, most of what you feel most likely comes from the changes in TQ managment making it feel like you have 400hp.

Congrats on the tune,...

actually its really not tuned that well(stock).... I mean its very conservative even on GM's standards and pig rich should i mention...The High FLow L92 heads and 10.5:1 compression pistons are where the gains come to play vs the 6.0.... My truck's tq sensors in the tranny (crank tq) went from what it was rated about 417tq to about 475tq consistantly. and have seen upwards of 500ftlbs on most runs...I know this isnt an accurate way of measuring but hear me out..... i have added about 60 lflbs at the crank, with just a tune.... and trust me the gain in ONE SECOND of the 1/4confirms that the tq sensors are somewhat accurate... but nothing like a LOAD BEARING DYNO.... those are kind of rare.. but put down real accurate numbers... but not to say regular dyno's dont... but the load bearing dyno can simulate the vehicle actually moving down the road and increase the load... this makes a difference.... regular dyno's cant do that... i guess thats why i am a fan!

i think the guy doing the tuning from NJ knows exactly what he is doing, but i am sure he is a little conservative as well... especially on a large vehicle that will probably tow....Me, well on my vehicle i am not conservative at all.... "if in doubt, MAX IT OUT" but when i tune my buddies vehicles i get a little conservative, since it isnt mine... thats not to say i dont do a good job, because i do, i just keep it a little conservative so that they dont do something stupid, blow it up, and blame me... lol

The 6.2 has a lot more potential, and when i get back to the states in the next few days its on, ill be tweaking the VVT cam tables... she will break 13.99 with just a tune and Cold Air intake... and yes, its a 4wd crew cab.....

tonygxp · June 17, 2010

I'm betting the 6.2 is tuned pretty well for 400hp at the crank. With that said, most of what you feel most likely comes from the changes in TQ managment making it feel like you have 400hp.

Congrats on the tune,...

actually its really not tuned that well(stock).... I mean its very conservative even on GM's standards and pig rich should i mention...The High FLow L92 heads and 10.5:1 compression pistons are where the gains come to play vs the 6.0.... My truck's tq sensors in the tranny (crank tq) went from what it was rated about 417tq to about 475tq consistantly. and have seen upwards of 500ftlbs on most runs...I know this isnt an accurate way of measuring but hear me out..... i have added about 60 lflbs at the crank, with just a tune.... and trust me the gain in ONE SECOND of the 1/4confirms that the tq sensors are somewhat accurate... but nothing like a LOAD BEARING DYNO.... those are kind of rare.. but put down real accurate numbers... but not to say regular dyno's dont... but the load bearing dyno can simulate the vehicle actually moving down the road and increase the load... this makes a difference.... regular dyno's cant do that... i guess thats why i am a fan!

i think the guy doing the tuning from NJ knows exactly what he is doing, but i am sure he is a little conservative as well... especially on a large vehicle that will probably tow....Me, well on my vehicle i am not conservative at all.... "if in doubt, MAX IT OUT" but when i tune my buddies vehicles i get a little conservative, since it isnt mine... thats not to say i dont do a good job, because i do, i just keep it a little conservative so that they dont do something stupid, blow it up, and blame me... lol

The 6.2 has a lot more potential, and when i get back to the states in the next few days its on, ill be tweaking the VVT cam tables... she will break 13.99 with just a tune and Cold Air intake... and yes, its a 4wd crew cab.....

that would be correct. His load bearing dyno actually calculates curb weight and drag coefficient, it's an amazing and very expensive machine. When tuning cars/trucks that people spend 10-20-30k+ on it's worth every penny. fits short wheel base all the way up to an H2..

pic of it when it was getting installed

Wingnut · June 17, 2010

That TTP?

tonygxp · June 20, 2010

That TTP?

yes sir. trying to convince him to get on here. He wants me to watch over the threads/posts, but neither he nor i have the damn time lol..

It'll probably happen soon enough. He just doesn't want to ignore people that have questions you know?.. Take care wingnut

kdixer · June 21, 2010

and trust me the gain in ONE SECOND of the 1/4confirms that the tq sensors are somewhat accurate...

In my opinion shift scheduling has more to do with shaving times than 10-20 hp IMO. If you do some datalogging the stock shifts take anywhere from .5 to .75 seconds to start bringing the rpm's up again. Your tuned TCM probably takes much less time. My 6 spd shifted 2 times from 0-60 mph. That alone is 1 to 1-1/2 seconds worth of no pull. A tuned 6 speed probably only shifts once from 0 to 60 due to raised WOT shift points. Not to mention you can adjust the commanded shift times for a firmer faster shift. That alone would shave some serious time.

That has just been my experience so far with the Diablo Predator v/s the Superchips Cortex.

tonygxp · June 22, 2010

and trust me the gain in ONE SECOND of the 1/4confirms that the tq sensors are somewhat accurate...

In my opinion shift scheduling has more to do with shaving times than 10-20 hp IMO. If you do some datalogging the stock shifts take anywhere from .5 to .75 seconds to start bringing the rpm's up again. Your tuned TCM probably takes much less time. My 6 spd shifted 2 times from 0-60 mph. That alone is 1 to 1-1/2 seconds worth of no pull. A tuned 6 speed probably only shifts once from 0 to 60 due to raised WOT shift points. Not to mention you can adjust the commanded shift times for a firmer faster shift. That alone would shave some serious time.

That has just been my experience so far with the Diablo Predator v/s the Superchips Cortex.

i don't tune but have been around it for years, watching my friend dyno tune for four years as well. It's way more thna just ramping up shift times, you're oversimplifying Professional tuners a great deal. I have watched COUNTLESS people bring it screwed up trucks, cars, even corvettes due to other tuners inexprience or amateur's thinking they understand all the small details when planning out a tune. Just my experience, but thank for the comments, i due agree with the TCM cutting times down significantly as these engines are pretty maxed out on timing from what i witnessed on mine.

coryf79 · June 22, 2010

and trust me the gain in ONE SECOND of the 1/4confirms that the tq sensors are somewhat accurate...

In my opinion shift scheduling has more to do with shaving times than 10-20 hp IMO. If you do some datalogging the stock shifts take anywhere from .5 to .75 seconds to start bringing the rpm's up again. Your tuned TCM probably takes much less time. My 6 spd shifted 2 times from 0-60 mph. That alone is 1 to 1-1/2 seconds worth of no pull. A tuned 6 speed probably only shifts once from 0 to 60 due to raised WOT shift points. Not to mention you can adjust the commanded shift times for a firmer faster shift. That alone would shave some serious time.

That has just been my experience so far with the Diablo Predator v/s the Superchips Cortex.

Yea, well i guess you could always get a powerglide instead of that six speed then you wont have to worry about losing time during those shifts.... With all due respect the fastest i have heard from all of my tuner buddies, is about 3-4 tenths of a second in the 1/4... by properly tuning the a6... and to be quite honest, i know you wont get those results from a diablo hand held tuner... You dont have 1/16th of the parameters that you need to achieve those results... Its a lot more complex than what you see on the Diablo... i assure you

And i would have to agree with Tony...

I know its your opinion and i respect it.. but, i have to disagree with you...

kdixer · June 22, 2010

DANG!!! I cannot win.

I was not bagging on custom tuners at all. All I am saying is it is hard to drop 1 second off of 0-60 times with a 20hp increase. And while 20hp is a significant increase, it alone is not enough to get a 5k pound vehicle to 60mph a full second faster. However the TCM tune via an aftermarket tune of any sort will probably shave more time off than a 20hp increase. And my sole point was that the factory TCM tuning takes alot of time to complete shifts utilizing TM and soft pressures.

My personal experience with the stock TCM tuning in my truck is that it shifts twice before the vehicle reaches 60 mph. So if the TCM is tuned so the 6 speed shifts into 3rd after 60mph (stock tune is around 55mph) then that alone would is worth atleast 1/2 a second (or whatever the elpsed time is to complete the shift).

My 0-60 time stock and with the diablo was in the 9.5 second range (5.3 CC 4wd 6l80e). After I installed the Cortex it was 8.4 seconds. I do not race and do not preach handhelds are superior. I chose that route because it was my only at home option. It is currently not convenient to tune the 6spd at home any other way. And as you eagerly point out, my tuning knowledge is limited so I did not opt for efilive or hptuners at this point.

coryf79 · June 22, 2010

FYI, the approx 1 second in the quarter mile was achieved without tuning anything besides shift rpm points in the A6... she is now .3 tenths faster than that with my tune of the tranny... SO 10-20 REAR WHEEL HP was the causing factor for Elapsed time increase... These are my results on my tune, done at the race track with multipue runs done for a consistancy check.. and well ITS VERY CONSISTANT.. within a huhdred of a tenth.. 3 runs stock, 3 with motor tune..etc... (ie, shift timing, line pressures, shift inertia factors, shift torque factors and so on were not touched until my truck ran 1 second faster over stock).... however ENGINE TM WAS REMOVED...ENGINE TM ONLY..NOT Transmission TM... personally the numbers speak for themselves when it comes to my truck..

So once again, i respect your opinion however i have to gracefully disagree, based directly on the data i collected of of my truck, and my tune.... others are subject to vary....

kdixer · June 22, 2010

FYI, the approx 1 second in the quarter mile was achieved without tuning anything besides shift rpm points in the A6... she is now .3 tenths faster than that with my tune of the tranny... SO 10-20 REAR WHEEL HP was the causing factor for Elapsed time increase...

All I can say is congrats!!! A full second gain in 1/4 mile. That is huge for 10-20 hp increase.

According to this calculator it would require an additional 70hp to get a 5000lb vehicle to gain a full second. FYI 1 pound = 2.2 kg

http://www.torquecars.com/tools/quarter-mile-time.php

I used 300hp for my baseline. The higher your initial HP, the higher the increase must be to shave time. So if 20hp increased your 1/4 time by a full second, that would mean you started at about 120hp. Personally I would not admit to that...LOL

How many times does it shift in the 1/4 mile? How many times did it shift in the 1/4 mile stock?

Who does the tuning is irrelevant because physics, gravity and frictional losses are unavoidable.