Pre tuner install ?

[homebrew]

I have a 14 5.7 QC Express, It is leveled with bils and running 34in tires. I ordered up a vararam intake and an intune with hemi fever tuner. Im looking to recapture any MPGs that I can . Recalibrating for the tires is a start, which tunning will yeild the best reseults as far as mpg's are concerned? TIA

 

[BlownGP]

You won't be gaining much MPG with those mods. Maybe 1 or 2 if your lucky.

Getting taller tires is just going to make it worse.

 

[Pull Ya]

I hate to say it but IMHO the best mileage your going to get is if you leave your truck stock. There may be few exceptions but not many. It's pretty hard to tune for performance and high mileage at the same time.
Jay

 

[homebrew]

Post mod follow up. I installed the vararam and the tuner with the 87 tune. I opted for the HF add on. With the 87 tune and recalculating for the tires I am back up to 22.7 at 65 mph which is great as far as I'm concerned. I tried out the 89 HF tune and wasn't really impressed, not much seat of the pants excitement and lost about 4 mpgs down to 18 hwy. haven't tried the 92 tune yet. For now I'm sticking with the 87 tune running 89 octane truck runs great has plenty of power and is averaging almost 23 mpgs!!!

 

[xrsman]

Ask him to change the target stoich to 15.0 and also leave the part throttle spark stock. You can do this on any octane tune and get better then stock MPG running 89-93 pump.

Would that bring some of the performance down? What makes the mileage increase when you do this?