do you need to run premium gas with super charger or not?

the reason manufacturers are switching to smaller forced induction engines is because the have to meet the next tier of epa/efficiency standards where it will be required to make so much power per litre. Toyota(and most "American" cars) are obviously way behind even with the newer 2016 engine. Just look, a lot of overseas vehicles make way more power from a smaller displacement.

 

ok so less tall tire wont help on mpg, got it. now I have to think how to get a 2" drop on the truck, I really dont want more then that, im just tired hoping up to get in and banging my feet on the door sill.

so if I keep the same stock diameter and height, it wont change the rpms or effect speedo accuracy, but if I get a narrower tire like a 75 instead of a 65 so its only 8.5" wide rather then the stock 10.5" wide, that should help increase the mpg im getting by reducing the surface friction on the tires and I would "assume" its not as hard to turn a narrower tire, albeit im sure that change is minor and wouldn't be noticeable except maybe less wet road traction.

im having realistic expectations on this and only expect to only get "maybe" 1-2 mpg better

 

Oh i bet running a narrower tire would help, like youre saying. Even less air being pushed too, unlike the wider meats, i bet that alone would have some sort of improvement. It dosent seem like it takes much accessory type stuff or whatever and next thing ya know it seems youre really being held back by the increased wind resistance.

And back to my last comment, theres olot of factors at play there(bigger or smaller tires) even though a higher rpm at cruising speed will be the result of running a smaller diameter tire. Id also maybe assume since its effectively regeared to a lower gear, that you would get up to speed with a little less effort and a lighter throttle foot. So, idk it could be a wash on mpg's with that considered. But again itd be all about your driving styles/habbits and what you are driving in terrain wise, on and on...you know.

 

They also don't have some of the retarded emissions controls we have, and they've adopted diesels.

You also proved my point lol, added power, lower displacement = higher efficiency.

 

European standards are more strict and include efficiency as well, something the Americans have yet to include(they just talk about it). I'm not disputing adding forced induction and performanbce, everything I own has forced induction. What is sad, I have a 4.0 that barely puts out more than 300hp, compared to a 2.5 that is pushing 350hp and a 4.2 that is pushing 500hp.

 

Small displacement is one thing but cramming 30 lbs or air pressure (and adequate fuel) into a cylinder is seldom going to result in anything I would consider good gas mileage. Turbo chargers are inherently more efficient than super chargers and can even be more efficient than N/A if tuned appropriately and I believe they are on the cusp of automotive technology. However that goes a long way from saying that by simply adding a turbo to your engine your gas mileage is going to increase, chances are very likely you will achieve the exact opposite.

There is far too much at work to compare a small displacement/ high boost motor to a large displacement/ N/A engine just because they produce the same peak HP and torque.

OP if you're looking for more kick out of your 3.4 I would absolutely recommend a s/c. On average I wheel about half my tank away in 4-low at 3000 rpm and the other half in town, stop and go b.s. and I get 17 mpg consistently and 20 highway.

On the other hand, if you're looking for great gas mileage... don't drive a truck. And to address your thin tire theory, rolling friction is proportional to the amount of contact you have with the ground. By decrease your tire width by a factor of 2 for example (cutting it in half), you are decreasing your rolling friction by that same factor. However, rolling friction plays a very small role in the net force that resists the motion of the truck. So yes and no. Yes you will increase mpg but it will be a marginal increase. If you're looking to optimize your efficiency there are a lot of things you can do and they generally revolve around the concept of keeping things clean and lubricated. As far as modifications go there is virtually nothing you can bolt on that will actually increase gas mileage.

 

just looking for anything I can do besides proper alignment and tire pressures to increase mpg, im "happy" with the power of the 3.4 but naturally added power is always ok as long as it doesn't cost a lot or degrease mpg.

if there was a single thing that drives me nuts and im willing try to fix at any cost, is how the CC has a lead foot and keeps double downshifting to go up any hill or incline or even driving into a stiff head wind as soon as you get 1mph below the CC setting it floors it to gain speed, and that's an unsolvable ECM issue so...

 

^^ It does that because the torque band doesn't extend very high. My minivan's cruise control is similarly not embarrassed to just mat the throttle to maintain speed on the highway. It's dorky, sounds dumb and just results in more full-throttle waste. But if "I'm" driving, I can anticipate the hill and slightly increase throttle has the ascent begins. Result: no 2-gear downshifts, no screaming engine. The cruise just waits too damn long and then it's "oh shit we need speed!"

First time I took the truck on a long trip it was clear it was in its "easy chair" comfort zone at about up to 65mph. This is with 265-75/16s, so the effective gearing's slightly taller than normal. But at 70mph the truck is OK but becomes "busy." Suspension squirms more, trans downshifts on hills. At 65 it pretty much stays in overdrive all the time. This is mostly unloaded for cargo but carrying 3-4 people.

So I don't try to maintain 70mph for very long: It's tiring on the driver to experience "so much" is going on on a long trip. This is in stark contrast to basically every car I've ever owned, where 70, 80 is no big deal (even with 4cyl economy sedans) and our current zoomer (7th Gen Accord V6 6MT) has more effortless speed and quickness than my driver's license can bear. So it's a bit of an adjustment with the truck.

In normal cruising the 3.4 seems happiest at about 2200rpm. Puttering around town or going down the Interstate, it's looking to do about 2200rpm.

 

Absolutely!!!!!

 

This guy knows what's what.

 

Just rebuilt the superchager and got a pillar guage, now I know that I'm pushing 9 pounds of boost with
premium Gasoline.