Mpg

[foosed]

i read the thread on mpg for a 402, and i realize that i chose the wrong truck for mpg, and i knew that from the beginning, but is there any way to get better milage in my 72 4x4 lwb with a 350/350. i plan on making it to a swb, which should help, as well as changing my exhaust to something more fuel efficient. Longhornman said he got 12 to 15 in his suburban with a 402, so i think this is achievable for me. any help would be great!

[FLDBRED]

Going to the 700r4 would help!

[foosed]

http://www.agsvaporizermpg.com/ I found this, looks interesting. Has anyone done this with our trucks. Again any help would be greatly appreciated.

[mr48chev]

A good free flowing exhaust will help unless you keep your foot in it to hear the pipes.
Without the boat on the back I get about 12 with my 350 in my 71 3/4 two wheel drivewith the Edelbrock Performer, Holley 640 spread bore and Hei with dual pipes. That's with 4.11 gears and 245-16 tires.

I'd say that all of the usual stuff factor in.
State of tune
tire size and pressure
Wheel alignment right on the.
No extra junk in the back. I haul a tool box that totals about 250 lbs and know that it costs me a bit of mileage but it is worth it to me.

[foosed]

thanks for the info!

[69GMCLonghorn]

I can't emphasize enough how getting the RPM's down can help your MPG. Now, you have to analyze your engine and decide how low you can go before you're lugging.

Also, the more gears, the better. So, as stated above, the 700R4 would be a better option than just gearing up the rear end.

You may need to play with it though. Get the 700R4, CALIBRATE YOUR SPEEDO, and see what your MPG is. Then maybe tempt fate and raise the rear end (and front end in your case) ratio by 1 and see if the mileage improves again. If it goes down, then you know you went to far and you should put the old gears in it.

[cdowns]

while you're chopping the truck up you could dump the 4wd and gain MPG too

[foosed]

i would like to have the four wheel drive as i live in south dakota, which we all know is no stranger to snow and rain. thanks for the comments though!

[mclairmo]

Keep an egg under the gas pedal and make sure you don't break it.

[foosed]

Has anyone done or heard anything at all about fuel vaporizers. This really looks interesting.

[69GMCLonghorn]

Originally Posted by foosed

Has anyone done or heard anything at all about fuel vaporizers. This really looks interesting.

Sounds interesting, but my semi-educated guess is that it's more gimmic than anything. Kind of like the Tornado...

[mclairmo]

The only way to significantly increase mileage is to spend a lot of money on fuel injection, overdrive, cut weight, etc. However, IMO, you will not get that money back in fuel savings. Not really worh the effort. Just make sure you have a mild conservative combo, tune it up best you can, drive it like a grandpa and hope for the best mpg.

[69GMCLonghorn]

Originally Posted by mclairmo

The only way to significantly increase mileage is to spend a lot of money on fuel injection, overdrive, cut weight, etc. However, IMO, you will not get that money back in fuel savings. Not really worh the effort. Just make sure you have a mild conservative combo, tune it up best you can, drive it like a grandpa and hope for the best mpg.

I do agree with you; you will NOT come out money ahead. But! What none of us has brought up yet is the driveability factor! First of all, the better the mileage, the longer you can go between fill ups, which is SUPER handy if you get out in the middle of nowhere on a long run.

Also, if it gets poor mileage because of low gears, it's just not comfortable to drive at highway speeds for any great distance. And you're always concerned with (or SHOULD be concerned with) over-revving, etc. Plus, anything turning 3000 RPM is going to last longer if it's only spinning 2000 RPM. Just logical.

[mclairmo]

Originally Posted by 69GMCLonghorn

I do agree with you; you will NOT come out money ahead. But! What none of us has brought up yet is the driveability factor! First of all, the better the mileage, the longer you can go between fill ups, which is SUPER handy if you get out in the middle of nowhere on a long run.

Also, if it gets poor mileage because of low gears, it's just not comfortable to drive at highway speeds for any great distance. And you're always concerned with (or SHOULD be concerned with) over-revving, etc. Plus, anything turning 3000 RPM is going to last longer if it's only spinning 2000 RPM. Just logical.

I agree. If the truck is driven daily and needs to drive like a newer truck then its totally worth it. I personally don't drive these older vehicles daily and prefer the simplicity and lower cost of the oem fuel sucking devices.

[foosed]

Originally Posted by 69GMCLonghorn

Sounds interesting, but my semi-educated guess is that it's more gimmic than anything. Kind of like the Tornado...

I too was a bit leery about this, but i thought i would run it by you guys(who know alot more about this stuff then i could ever hope to know)

Originally Posted by 69GMCLonghorn

I do agree with you; you will NOT come out money ahead. But! What none of us has brought up yet is the driveability factor! First of all, the better the mileage, the longer you can go between fill ups, which is SUPER handy if you get out in the middle of nowhere on a long run.

Also, if it gets poor mileage because of low gears, it's just not comfortable to drive at highway speeds for any great distance. And you're always concerned with (or SHOULD be concerned with) over-revving, etc. Plus, anything turning 3000 RPM is going to last longer if it's only spinning 2000 RPM. Just logical.

I dont plan on spending a whole lot on this, and I completely agree, it is much more convienient to get better milage.

Originally Posted by mclairmo

I agree. If the truck is driven daily and needs to drive like a newer truck then its totally worth it. I personally don't drive these older vehicles daily and prefer the simplicity and lower cost of the oem fuel sucking devices.

Yes please keep in mind this is my daily driver.