6.0L power

HDdave · February 6, 2007

What else can I do to my 6.0 to get more power out of it, and maybe a little more milage too? I already have a true dual exhuast system, and a cold air intake. I would prefer to get a programmer rather than a custom tune, just so that I can adjust things if I'm not pleased with them, and use the lower level for daily driving and fuel milage, and use the higest level when towing.. Also I would like to know what is so much different about the newer 6.0's that have so much more power than mine..

Ductape · February 7, 2007

What kind of mileage are you getting now?

In general I think tuned for best power and best mileage is not really different. You just want the engine to run as efficiently as possible.

By my estimates ~1 mpg gain (if I get that) with the tune I can break even cost wise on 93 octane vs. 87.

Can't tell you yet what the tune did MPG wise. Having too much fun with the loud pedal. I was around 15 highway before.

DT

HDdave · February 7, 2007

Right now I get 12.5 city and 12.5 highway with 285/75's, true duals, and a cold air intake. I would keep my truck on 87 not matter what type of tuning or programmer i got.

Billdog350 · February 7, 2007

I'm getting right around 12 city and 13 highway (at 70-75mph) with 285's and a custom tune on my LQ4 with 4.10's. Looks like thats about all these trucks are good for. I guess DOD and higher hp with the new 6.0's must be helping get closer to that 20mpg claim?

HDdave · February 8, 2007

Yeah, I just don't want it to get any worse. Actually when I first got it, it had 245's, no performance mods, and a leer fiberglass cap and I got 13.8 mpg. Ever since the 285's it hasnt came close to that, but I knew that going in. The torque management is really what kills me, for as powerful as that truck is, it is a complete dog off the line. Now if I punch it from like 20 thats a different story. The truck STRUGGLES to roll them from a stop light, and I know thats the fault of the TM, so I really want rid of that with whatever programmer I chose to get.

GeoHawk · February 8, 2007

The new 6.0L truck engines are getting most of their power bump from a slightly higher lift cam, new heads, and mostly variable valve timing (VVT). The torque numbers for the new 6.0s (L76 and LY6) are not that much higher than the old 6.0s (LQ4 and LQ9), but the big HP jump can probably be attributed to the VVT.

As far as getting a tune, I didn't dyno my truck when I got a tune, so I can't really tell if there was a big hp boost. But mileage went up slightly and throttle response is much better with the TM removed.

Billdog350 · February 8, 2007

HD Dave....its actually not the TM that makes our trucks dogs from a stop light! Make sure you go with custom pcm tuning software or just have a professional do it like wait4me or the million other guys doing it. I use EFI Live but since it's $500+ for the package for your vehicle, it might not be worth it to you.

I noticed while datalogging that when you punch the throttle from a stop, your timing goes so single digits and sometimes NEGATIVE! I looked at my timing table and low rpm and high vacuum is where the problem lies. A simple increase in timing at that point (I went from 0 base timing to approx 15 deg which is still conservative) and the truck is a total animal. I can spin the tires on a launch now even with a few hundred lbs in the bed! The truck is MUCH more responsive and I believe that my in town economy has improved because I don't have to give it as much throttle to get moving.

Of course you need to datalog after and make sure you're not getting any knock....overadvanced timing is a bad thing too.

TM will help you on the shifts....as well as increasing your "driveline max torque" value which limits the torque to your driveshaft/axle/transfer case thru a bunch of calculations and overall reduction in timing and or throttle.

With our trucks, I'd recommend a custom tune (or custom software if you know what you're doing or willing to learn) more than any other mod. Headers, intake, exhaust, gears, etc are all marginal gains (gears feel good but don't give you actual hp). Once you've been in a truck with custom pcm tuning you'll know what I mean. A hypertech or whatever doesn't even come close to a good custom tune. We're talking 5-10hp at most with a hypertech and 50+ with a custom pcm tune!!!

HDdave · February 9, 2007

I would love to do that EFI live thing, but I can't justify spending that much. I just want this motor to run to its full potential without imploding my tranny or transfer case. Where can I get ahold of some of these custom tune places?

GeoHawk · February 9, 2007

I would love to do that EFI live thing, but I can't justify spending that much. I just want this motor to run to its full potential without imploding my tranny or transfer case. Where can I get ahold of some of these custom tune places?

I got mine thru www.pcmforless.com and was very happy with it.

I know tbyrne motorsports (a site vendor) sells westers tunes. I've also heard of wait4me tunes, but don't know off the top of my head what their website is.

HDdave · February 11, 2007

So the advantages of a custom tune over a programmer is that they will tune it to match any other mods you have, and eliminate TM to however much you want gone...

GeoHawk · February 11, 2007

So the advantages of a custom tune over a programmer is that they will tune it to match any other mods you have, and eliminate TM to however much you want gone...

Correct. I don't have any other mods on my truck and the tune made a very noticeable difference to its performance. I can imagine the the gains with some bolt ons (exhaust, intake, etc.) would be significant. The only thing better would be a dyno tune, but those get really expensive and time consuming.

HDdave · February 13, 2007

What about a cam? I've heard that they give a really nice power gain and ive also heard of MPG increases...

GeoHawk · February 13, 2007

What about a cam? I've heard that they give a really nice power gain and ive also heard of MPG increases...

Cams are always a great way to go to increase power, as the stock cams in our motors are really pretty mild. But they are also designed more for efficiency and emissions than for peak power. The drawback to a cam swap is that they are usually more $$ and labor intensive than basic bolt-on modifications.

Flowtech Induction is an excellent shop than can custom grind you a cam to fit any other mods you might have. You just tell them if you are looking for big torque increases, HP, or whatever you want and they design a cam to meet your needs. They will probably be a little more $ than a regular "off the shelf" cam, but it is tailored to your specific needs.

Billdog350 · February 13, 2007

I would love to do that EFI live thing, but I can't justify spending that much. I just want this motor to run to its full potential without imploding my tranny or transfer case. Where can I get ahold of some of these custom tune places?

Keep in mind that many "mail order" tunes require you to ship out your stock pcm or buy a spare for them to tune. Obviously your truck would be down while the pcm is being tuned if you go that route. If you do an "in person" tune, they're usally more expensive but also are WAY more accurate and custom for your vehicle. A mail order tune can't adjust your WOT AFR properly and timing won't be optimized for your motor, just some safe zone that's a bit more than stock. If there are issues with the way your tranny shifts, torque converter locks, etc....it means shipping it back for another tune.

Plug in tuners don't really do much...maybe a bit in your tranny but not much as far as motor changes....

Custom mail order tune: $100-250 PER TUNE

Custom dyno+street tune: $300-$500 PER TUNE

Hypertech or similar plug in: $330

Buy the software and cable: $500-700 UNLIMITED TUNES (plus you can datalog, reset codes, turn off CEL)

If you're thinking of changing a lot of things on your truck, or just like being able to fine tune things....and are handy with a laptop...you can do quite a bit yourself. There are tons of free resources on the internet for self tuning directions, including this site, fullsizechevy.com, EFI Live forum, etc.

HDdave · February 15, 2007

One of the major problems with that is I'm very computer illiterate, and noone in my family has a laptop... I will look into the cams more, it just blows my mind that the new 6.0's can have that much more power, and just as good if not better milage than I'm getting...I'm wonderiing what it would do to put a cam from the new Vortec Max into the older LQ4.. It should fit, plus then you wouldnt be risking any engine reliability or anything...