Yes I saw you had a silverado. I also managed to READ that you told me you got 13-14 mpg with it. However what lead me to believe you knew more about camaros than silverados is your blunt statements such as "no mod is going to save you money on gas."

And yes I'm very much aware that physics has and always will be the same. However there is a HUGE different between the efficiency of a gen I engine and a Gen III/IV engine especially in the stock form. The spark tables are extremely tame from the factory, torque management is also another factor, fuel injection also provides for a much more efficient setup than a carb setup.

There are a number of guys on here who have achieved 25 mpg with a 5.3L v8 and I guarantee you no Gen I/II engine could ever do that.

Do your homework a little more and use the search button. You'll find plenty of great info that only further proves my point.

 

I have an 02 Silverado Stepside W/Std. cab that gets around town mileage of 16.2 - 16.9 mpg and road mileage ranging from 19.7 - 22.9 mpg @ 65, depending on trip length.

It's a 5-speed manual with 3.73 gearing and 255/70-16 tires which I run @ 35 psi. It's also a 6.0l with mildly cleaned-up 243 heads w/2.02 intakes and 1.57 exhausts. The cam is an LS6 (308) installed @ 4* advance. The exhaust is ASM coated LT headers into functional cats and 70 series Flowmasters. The tune is a Nelson mail order and is pretty close to optimal for this setup. It would probably be even better if I resized my marginal injectors to get the pulse duration down.

It gets mileage very similar to the original 4.8l as long as you stay out of it. The around town will fall off by 2 mpg with a few quick trips through the gears.

All the basics to mileage apply here: tuning, drive with moderation when you want mileage, keep your filters and oil clean and your tires inflated.

Gen I and II TPI L98 Corvettes and some Camaros could routinely top 25 mpg on trip mileage and were still decent performers in their day.

 

I average from 14.5 mpg to 17. I drive 75 miles to work one-way, 70 all highway and 5 city. My consistent average is 16 mpg. I've only seen a 1 mpg increase in changing my driving habits by slowing down to 65 mph. Which if you drive in Houston it isn't worth it!! The only thing I can say is that my mpg hasn't gotten worse with modding. And if it matters, I have 190k miles.

 

I'm not sure who you are trying to impress by spouting off a few big words. Yeah, drive a car around enough and even the most minuscule gains will pay off. sure.

Essentially, by gaining 3mpg on an 11mpg truck, you were saying that about 33% of the power your engine made went to powering the fan in the city.

Sorry, that **** isn't going to fly. This is assuming the fan is engaged all the time. Carry on as you will; I'm not interested in arguing this with you.

Trey
24mpg
Mechanical Fan

PS: I must have failed to mention I was a powertrain cooling engineer, for what it's worth.

 

What words am I using that are too big? I only assumed you knew what I was talking about since I am stating facts and because I assumed you knew what spark tables and torque management was.

Also, your logic is a little screwed up. You keep saying that 33% of my engine's power went to turning a fan? It has VERY LITTLE to do with horse power. It has to do with efficiency.

I am not saying for a second that everyone gains 3mpg with electric fans, however I see no reason why everyone can't gain 3 mpg with a tune. I personally gained 3 mpg city and .5 mpg on the higway with electric fans due to the fact that my truck no longer had to turn an 8 pound 22" fan for 2 hours at a time in standing traffic. Sure electric fans are only going to add maybe 5 horse power at best but when your engine is no longer turning a clutch fan for 3 hours straight then that adds up very quickly.

I'll state it again, the spark tables are retarded by quite a bit in stock form, they also run extremely rich, torque management is another issue that hopefully you know affects gas mileage. There is TONS of stuff in a tune to make it more efficient. We even have a lean cruise table which I believe sets the AFR's to 15.7 instead of the normal 14.7 to allow for optimum gas mileage.

I would love to argue about it, but you don't seem to want to listen to what I have to say. I'm providing you with factual evidence and you keep making responses like: " I'm not sure who you are trying to impress by spouting off a few big words." or " For the record, physics hasn't changed much since 1969, SBC or Stock car engine."

We're both not idiots, I know that much, but listen a little to what I have to say. I'm not an expert, but I know quite a bit about LSX based engines. There's a big difference between an LS1 and a Carbed 350 small block.

I'm trying to have a civilized "arguement" about the issue, and you keep attacking my creditability.

 

... for one thing cruise control sucks down ur gas it wont let off the gas in part that u would so its doo doo ok for highways. Like if ur going downhill u probley let off the gass a little cruise control wont it will just stay on it

 

I like my mileage and dont Think its too bad for a Truck.
1999 ecsb 5.3 3.73s all bone stock, except for a little bit bigger tires
and i get 22 all highway (oklahoma to texas) and about 15.5 to 16 in city

And i will say that where you live has a lot to do with your mileage. texas is pretty flat but im sure mileage in a mountanous region would be worse. plus climate and air quality.
Just a thought

 

E-fans, wheatley tune and a tunneau cover. on a 99 5.3 getting 16 city 19 highway

 

uhhh...
So now a mechanical fan reduces the combustion efficiency of the engine?
Let me spare you the research- it doesn't. Well, maybe it does- more load = more efficient (not less)

1/3 less fuel
1/3 less power being made
you are claiming 1/3 less fuel use
that means your engine is making 1/3 less power
conservation of energy says it is going somewhere
You are saying it goes to the fan

edit: I cant believe I got sucked back into this.

 

Alright guys, we've gone around the world on this. Let's just say efans CAN give you mileage relief and how much varies from vehicle to vehicle. It's 12:00. I'm tipping one back for each of you guys.