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[INDEPENDENT_1]

I recently purchased a 2014 GMC Sierra with the all new 5.3L Ecotec engine. It has an all aluminum block (and heads), variable valve timing, direct injection and I think it's 11:1 compression. I'm interested in doing cold air induction, cat back exhaust and flash tuning or possibly dyno tuning it. Does anyone have any advice on these upgrades and what can be expected for power increase and possible fuel mileage increase or decrease from doing these upgrades? TIA for any feedback or advice.

[deldago]

There are many cold air systems that will work, just get one that replaces the whole system. Volant and K&N make the most popular. I like the Volant better because the filter is not exposed to the hot air under the hood. Here is a link to one.http://www.autoanything.com/air-intakes/61A1817A0A0.aspx .As far as exhaust there is a problem. GM has installed a valve near the end of the exhaust (look behind your passenger rear tire) and it's job is to deaden the sound of the engine in 4 cylinder mode. When the engine shuts down fuel to 4 cylinders the engine makes a fluttering noise for lack of a better term. This is kept in check with that valve. If you remove it the sound is very pronounced in the cab at highway speeds. I have had several customers remove this valve and none are happy with the results. I would call Borla and see if they have a fix before going to a corner muffler shop and have them do an exhaust change without taking this into account. And be sure whatever exhaust you go with that it is stainless steel so it will last. Why take stainless off and replace it with regular steel that will last maybe 4-5 years? As far as tuners, the most versatile and easy to use is Bully Dog,(http://store.newlevelmotorsports.com/budogtrdoggt3.html) and they have a nice display that you can set up with various instruments and readings. As with Harley, GM is watching for tuners also so if you are not in good with the dealer take the tuner off so they can't hassle you before warranty work.

[OBB]

Lots of good info here:
http://www.gm-trucks.com/forums/

and here:
http://www.performancetrucks.net/forums/

I believe the 2nd one is maintained by the guys at Nelson Performance. They do a lot of custom tunes for GM peeps.


If I had the latest and not-so-greatest 5.3 with the AFM, I'd find a way to disable it with a tuner. Too many issues with it after extended use that GM has taken since '07 to try to get worked out.

Another option is the Diablosport products. Either the Intune or the Trinity. There are programmers all over the place that can write a tune for you, email it to you and you can then upload it to your device and then to your truck. https://www.diablosport.com/product-search.html

I have a custom tune for my old DS Predator in one of my avalanches that was done by a guy from their site.

[VaEagle]

I agree with above statements. In my experience CAI are mostly for looks or increasing intake noise, only minor gains in performance and they do nothing for improved gas mileage despite the advertising hype. Many owner reports are positive on first install, just my .02 but I think they are trying to convince themselves they spent hundreds of dollars for good stuff.
I have noticed performance improvement with a good CAT back exhaust. My personal preference is for Corsa Sport, it is a stainless system with lifetime warranty and is famous for NO Drone in the cab.  www.corsaperf.com

[INDEPENDENT_1]

 Thanks for the feedback and the point about the valve and 4 cylinder mode is something that concerned me. I hate the sound of 4 cylinders in any form of transportation but at the same time, that's when the fuel economy really goes up.
 As for the CAI, I agree that having the element open to the engine compartment pretty much defeats the purpose. Seems like almost false advertisement to call it CAI if it's drawing hot air off the engine.
 For the tuning, I had decided I would get a new ECM and use it to flash and keep the stock one to use for warranty work. I don't want to throw away a 100,000 mile warranty. Ohiobellboy, what did the tune do for you? Where the gains or losses considerable? Also, what kind of problems have they had with the system that goes from V8 to 4 mode?
 I have always been more of a GM guy. I looked at buying a new Ford this time but I wanted a V8 in a half ton and IIRC they don't offer that anymore. I also looked at the Dodge and drive one too. They run great with the Hemi V8 but they don't seem to hold their value very well and Toyota just didn't feel as roomy to me.

[deldago]

The 8-4 engines are really hard to make sound right when in 4 cylinder mode. It was so bad on my 2010 Camaro with a GM performance exhaust I sold it. I couldn't stand the stock quiet exhaust and the 4 cylinder drone was even worse. As far as gas mileage gains, that has always gone the wrong way for me on everything. A heavier throttle foot to hear the roar I guess!

[INDEPENDENT_1]

I assumed with the tuners you could turn the V4 mode off? I know if you put a supercharger on it turns that off. If I decided to leave the exhaust alone to avoid the V4 sound issue and to get the benefits of the fuel economy it offers and just decided to get a tune for it, what benefits could be expected from just the tune and possibly the CAI?

[INDEPENDENT_1]

Still curious what is "not-so-great" about them?

[OBB]

Still curious what is "not-so-great" about them?

Sorry for the delayed response. I've been painting in the house all day.

The tune I had written for me was to adjust shift points and timing. I also did away with the clutch driven fan and installed the electric fans out of an 05 Silverado. Might have gained a few horses there but the truck's never been dyno'd for proof. I know the a/c works much better at a stand still with the efans than the clutch fan. I had the programming for the fans put into the ecm so I didn't have to go to an aftermarket setup. At one point and time I could regularly get 19.5 mph on the highway running 75 on fairly flat ground. All my avy's are 4x4 by the way. That mileage took a nasty drop after the lift kit and bigger tires went on though.

Early models of the AFM engine when they went into 4cyl mode was dumping oil in places it shouldn't causing a lot of issues. By '09 they had most of the kinks worked out although my little brother's '09 Silvy  just dropped a lifter at 65,000 miles because of it.

[deldago]

GM has pretty much figured out any issues with AFM in the newer motors and the direct injection motors have been a big upgrade over the older ones, more horsepower and better fuel economy. Besides, they have you covered for 5 years and 100k if something comes up. Drive one of the new 6.2's with 420 HP and if it doesn't make you smile your heart quit beating. This is a pretty good explanation of the system and how it operates. http://www.videoatgm.com/videos/us/en/gm/Chevrolet/GM-Active-Fuel-Management-Tech/1780179993001/1

[FLSTFI Dave]

GM has pretty much figured out any issues with AFM in the newer motors and the direct injection motors have been a big upgrade over the older ones, more horsepower and better fuel economy. Besides, they have you covered for 5 years and 100k if something comes up. Drive one of the new 6.2's with 420 HP and if it doesn't make you smile your heart quit beating. This is a pretty good explanation of the system and how it operates. http://www.videoatgm.com/videos/us/en/gm/Chevrolet/GM-Active-Fuel-Management-Tech/1780179993001/1

Try one with of the new 6.2's with 465HP and 460 Torque and you will grin from ear to ear   Nothing like all that power with a 7-speed manual, and 30mpg when on the interstate. 

[GC_Super]

Thanks for the feedback and the point about the valve and 4 cylinder mode is something that concerned me. I hate the sound of 4 cylinders in any form of transportation but at the same time, that's when the fuel economy really goes up.
 As for the CAI, I agree that having the element open to the engine compartment pretty much defeats the purpose. Seems like almost false advertisement to call it CAI if it's drawing hot air off the engine.
 For the tuning, I had decided I would get a new ECM and use it to flash and keep the stock one to use for warranty work. I don't want to throw away a 100,000 mile warranty. Ohiobellboy, what did the tune do for you? Where the gains or losses considerable? Also, what kind of problems have they had with the system that goes from V8 to 4 mode?
I have always been more of a GM guy. I looked at buying a new Ford this time but I wanted a V8 in a half ton and IIRC they don't offer that anymore. I also looked at the Dodge and drive one too. They run great with the Hemi V8 but they don't seem to hold their value very well and Toyota just didn't feel as roomy to me.

Don't they still offer the 5.0 ?

[Fullsac Performance]

The 6.4 in my SRT has the 4 cylinder eco mode. Luckily it has an "ECO" swith that allows you to disable it. The second day I owned it I replaced the rear mufflers with a pair of 4" Bagger cans. Sounds good until that eco mode kick in, then's its horrible.

SG

[deldago]

The 6.4 in my SRT has the 4 cylinder eco mode. Luckily it has an "ECO" swith that allows you to disable it. The second day I owned it I replaced the rear mufflers with a pair of 4" Bagger cans. Sounds good until that eco mode kick in, then's its horrible.

SG

That is awesome Steve, what a great way to repurpose! Of course now with Harley parts on it you are going to have lifter failures and cam bearing problems!

[grc]

Don't they still offer the 5.0 ?

You can still order either the 5.0L V-8 or the 6.2L V-8 in an F150.

Jerry