Any secrets for a bumping MPG on 1998 305?

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Pinger

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Years ago, when I added the valance under the front bumper, I picked a tiny bit of mileage on the highway. I don't recall how uch, but I wasnt to say it was like 1/2 to 1 mpg... not a lot, but I was driving 100 miles a day, and calculated mileage for every tank, for awhile. That was with my 1-ton with 454, and 4.10 gears.
What cruise speed were you using? And lower than 1 mpg gain?
 

Pinger

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One other thing, with an automatic you want to accelerate hard enough to get the torque converter to couple well in the lower gears. I accelerate hard enough to get the engine up around 2,000-2,500 rpm before it shifts into the next gear. Get it into 3rd or 4th gear as soon as possible and going fast enough it locks the converter up. Driving around at low rpm slipping the converter only builds heat in the transmission and waste fuel.
There is also a case to be made for opening the throttle wide enough during early acceleration to minimise throttle related pumping losses - yes?
 

L31MaxExpress

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There is also a case to be made for opening the throttle wide enough during early acceleration to minimise throttle related pumping losses - yes?
To a certain extent yes. You want to use the torque of the engine not necessarily the peak hp to accelerate you efficiently. On the Vortecs that is in the 2,000-3,000 rpm range. Under load the engine has the best BSFC around peak torque.
 

94K3500PROJECT

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Here's a forum pretty much dedicated to tuning. 1st you wanna decided if you should do the 0411 (and WBO2) swap or stick with your black box.

www.gearhead-efi.com/Fuel-Injection/forum.php

I guess I better join over there ‍♂️
Im intimidated by my future mods but I want to do a Vortec harness/sensor and 0411 swap on my TBI truck with a TPI intake swap at the same time.

zero experience with tuning
 

94K3500PROJECT

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I dont think that chasing mileage is worth the bang for the buck.
If you have everything set up so the truck rolls in a straight line with no parasitic drag,
The mileage is what it is.
Thats when your foot comes into play.
And you need to consider the payback on investment.
And the potential loss of reliabilty from aftermarket parts and changes to the tune.
And the quality and failure rate of those aftermarket parts.
If this is a project truck knock yerself out bud.
Thats what hot rodding and car mods are all about.
If this is your only daily driver.
Dont **** around with any of these mods.
And dont for gods sake put a K&N ******** scam intake on anything.
Cold air comes from the outside.
Hot air gets sucked in from the inside.
Dont chase mileage, chase reliabillity.
Thats what these trucks are known for.
Get a Honda for mileage, put a K&N and a fart pipe on it
Blow it up in a spectacular way.
Tow the wreck home with the Chevy truck.

Gotta disagree here especially considering the MPG some guys seem to get.
If it’s a daily I guess the smart thing to do is get a high MPG daily.
The truck I’m building isn’t going to be a daily and the better MPG it gets the more likely I’ll be to take it on road trips instead of the other vehicles
 

thinger2

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Gotta disagree here especially considering the MPG some guys seem to get.
If it’s a daily I guess the smart thing to do is get a high MPG daily.
The truck I’m building isn’t going to be a daily and the better MPG it gets the more likely I’ll be to take it on road trips instead of the other vehicles
I am real curious about how much of an improvement you can get with mods.
Especially since I just filled up for $4.19 a gallon.
Im to the point where Im more likely to take the truck on long road trips and just close my eyes when I stop at the gas station.
Every gas station.
Only because after 16 or maybe 18 hours of driving I can fall out of the truck and crawl away from it.
I cant take that long of a drive in the econo cars without bending the door trying to pull myself out of it.
My Dad warned me about this.
He said son, sooner or later you reach Caddillac time.
I could run out and buy a new truck.
But there is no way on earth that i am going too spend more than I paid for my first house on a truck.
Hell, Im not even done wearing this one out yet.
My reasoning for behind chasing reliability over mods is thus,
I used to be a Dodge truck salesman.
That was a real eye opener.
New cars are the most sure way to suck money out of your pocket.
Well except boats. New boats are just dumb.
I havent had a car payment in about twenty years.
Over those twenty years I have probably spent about 15 grand or so on buying cars.
Maybe another 15 on parts.
But with sales tax and financing and insurance,
I have about $240,000 dollars more in my retirement.
I wrenched my way into having enough money in savings to put a down on houses that I flipped for profit because I knew that my crap wagon would make it down the road.
And I always keep a backup crap wagon.
Or two, or four.
Just my take bud, you dont build wealth and security by chasing dimes per gallon.
You build wealth and security by using your mechanical skills to stretch your vehicles as far as you possibly can.
Maintain it, drive untill it is beyond hope.
Buy another one.
Use the money you save over the next ten years as a down swat on a house.
Use the truck to fix the house, flip the house
Take the profit, stick it in the bank.
Form an LLC,
Run your entire business world through the LLC.
Register the truck through the LLC.
Take the tax depreciation for it.
And on and on and on.
Yes, this is a bit of a rant.
But, I started with a clapped out 83 K5 blazer back in about 91 or so.
I didnt have **** all of anything.
It was a bad idea.
Im 6'4"
Living in a Blazer sucked.
If you dont have a bunch of money?
If this is your dailly?
Dont **** with it.
Use it.
Many, many, many people have used the gmt400 platform as a step up over the years.
 

thinger2

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Hey thinger2... I agree with you, I dont miss car payments. Enjoy working in the older trucks and no desire to get a Doctors degree to work on newer autos.
Keep improving your skills for working on the old stuff.
Dont fall into the new car trap.
Put that money you didnt spend on a new car in the bank.
Do that all while you are young.
Bust your knuckles, fix that old **** and drive it.
Keep your ******* money.
Invest it, bury it in the back yard in Mason jars, Whatever.
Learn how to fix your crap.
You can do it so why pay somebody else?
Do it yourself.
The more you do, the better you get,
The better you get, the more you know.
The more you know, the more really fine people you meet.
With a Ummm.. Maybee..
Keep your money
Dont give it away
Use it for you and your family
 
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