I've always respected you and you did bring up valid points.. such as 22" wheels. They are heavy but not as comparison to my stock 20's. I was only going off my stock electronics but only because I have manually compared it in the past and it was pretty accurate at that time. I didn't manually do it this time because I didn't feel at the time line I needed to prove something. I did however get the specs on the fuel capacity between the Expedition and the truck and the difference was only 2 gallons ! So, visually the truck gets WAY better than her Expedition (which gets consistent 16 mpg )

And of course I knew all motors run on vacuum and also know allot comes into play with those readings...stated that because the centrifugal blowers aren't near as responsive at "tip in" throttle as a twinscrew.

 

on freeway only my truck on stock 18s and lowered does between 16-18mpg depending on freeway (hills or flat). 5.4 4speed 3.55s. My guess is its real close to stock.

 

What size tank do you have? Only reason im asking is with the gallons used and your gas gauge is showing about half a tank it doesnt seem to add up..

If you have the 26 gallon tank then wouldn't you be close to half a tank at around 13 gallons used?

Here a pic of mine and im just under half a tank with 13.5 gallons used and my average was 20.3 at 276 miles. Just doesnt seem like your mileage is adding up with where the gas gauge is..


Maybe im over thinking this

 

I disagree Crash. If it were true there would be a Pro-Charger on everything coming out of Detroit even if they just set them up to not boost but improve air flow. ProCharger themselves would be making a huge sales pitch regarding it as well.

Most importantly you cannot add air without adding fuel. So if the ProCharger or any other unit was making more air available to motor under normal driving and the motor was actually taking that air in then more fuel would be added to this keep the A/F ratios correct at 14.7. Improved VE is great but more air means more fuel. Also this increased air flow would reduce vacuum so you would not see the vacuum numbers reported here. If the additional air being offered were not accepted by the motor then the air would create resistance to the blades, rotors, or screws (depending on blower) and there by increase the hp draw of the blower. In other words it would take more energy to operate the blower.

If I am incorrect in my thinking then teach me why.

 

come on twinskrewd, this is the internet, no one would ever post something that isnt 100% true.

 

Uh oh thread is getting factually accurate! Let's see what happens now

 

Go-On3 are you still in Illinois? If you are what part? I'd love to meet up and check out the badass rig

 

Because when in boost bypass, the Procharger is nothing more than a [belt driven] idler pulley with a fan blade.

So then you're left with breathing mods. Improved tune, Long tubes (cat deletes) and a torque improving highrise (boss) intake. You'll basically never downshift on the highway. And the engine breathes happy which means its more effortless power.

And in Go-On3's case you also combine the improved aerodynamics of lowering the truck down to the ground.





FWIW my highest MPG to date in my all stock 5.0 is 25.7 (hand calculated) 85 miles @ 62 mph

My all time vehicle average is 18.7 unless you remove my heavy towing numbers, and im 19.2 mixed driving

I've got the exact numbers if you don't believe me.

 

giant difference in mpg cruising 62 to 75.

using the theory of the underdrive pulleys, reducing the resitance of turning devices. the procharger is a device and spinning the pulley has a measurable resistance.

i have had lowered cars, truck, and i have upgraded to bigger tires, rims. the mpg from lowering was not signifigant enough to show up. bigger tires, atleast 1 mpg drop. plus now my calibations are off.

i also had a vortech with a very conservative tune and i didnt notice much difference in mpg. not really better, not really worse.

could a slight tail wind, grade of the road and a better than average blend of gas explain the miricle mpg?

you have to admit with the manufactures having to meet strict mpg, and procharger fighting for their share of the market, if this was a normal thing, we would have heard about it.

 

They are saying the fuel tank reading is odd and it's easy to reset the mpg on a down hill part of a freeway and get high numbers. Just seems overly high for me too all things considered

 

Crash the avg mpg resets when you reset it. For the next 4-5 minutes the avg mpg will display just like the instant mpg display. Which btw is whatever your current mpgs are until enough data is collected for an avg to be displayed. During this time you can ease out of the throttle a bit or go down even the slightest grade and the avg read out will go up quite a bit instantly.

I can make it look like my Flex gets 40 mpgs. Lol. The car only gets 23avg and with me driving it's more like 20 mpg.😁

 

I reset my "average" on every fill up at the gas station

 

Doesn't it show the miles driven for that average at the same time? As well as the time elapsed? Mine does.

 

put it this way.

is is an awefull high mpg for a 4 door. 22", truck going 75 mph.

i would love to see it backed up with an old school pen and paper calculation and verification that the miles travelled are the same as what the truck is reporting.

i can honestly think of no situation where higher than averages numbers are not contested or people question the results. it is human nature to exaggerate and for people to doubt.

 

Never meant for this thread to become argumentative. I thought it was a discussion. On that note I think there are a number of possibilities here. So here are some pro's and cons.

Patman brought up the high rise intake, larger intake pipe, and long tube headers as allowing for effortless breathing. That's true at WOT. However at crusing rpm's these mods are useless for efficieny as the throttle butterfly is nearly closed stifling any free breathing. Hence the 21" of vacuum. This also throws out Crash's theroy regarding improved VE. In addition high rise intake's and larger dia intake tubes are worthless until the engine reaches a an rpm and a cfm demand high enough for them to become a restriction. In most cases you need to exceed 4500rpm's to gain any improvement from these 2 mods. It's the same reason head porting does nothing for low-mid range performance. As an example my 3.5" piping posed no restriction until I hit 11psi and was in the mid 4000rpms. Car manuacturers use the proper size intakes and tubing to allow the vehicle to breath freely to improve efficiency. Use of larger intakes and tubing results in a loss velocity. This loss in velocity allows the air to sit in the piping and intake longer and absorb more heat.

The lowering and LT headers could certainly help mpg's. Lowering reduces areo drag. LT headers help exhasut maintain velocity which is what helps get the exhaust out. This improves efficency. How much we don't know.

Added weight. The 22" wheels and tires are gonna weigh in around 80lbs a peice. That's a lot of rotating mass. In fact every 100 lbs of rotating mass is the equvilant of 400lbs of dead weigh being added to the vehicle. Thats why when you drag race you want the lighest possible set up.
The supercharger kit itself adds 45-60lbs depending on which Procharger you kit you have. Roots and twin screw kits tyipically add 80lbs.

Go-On3 has kept the 3.55 gearing in the truck and added 22" wheels which are likely taller then stock wheels. This would drop rpms and could improve mpg's as long as the rpm's don't drop below the power band of the motor.

And then there's the possibility as mentioned before that due to the injector swap the read out is skewed as the duty cycle would be incorrect.

Whatever the MPG's are is irrelvent. It's sexy damn truck and making good power. Want to see it go down the track. Peace.