Hey, new guy here, highschool student on a budget

[1990 GMC gas hog]

Alright, I bought this truck freshman year. I know I know but I have a huge interest in cars. I fixed this truck over that summer and she's my baby. I currently have a cold air intake and throttle body spacer, and she's getting about 16-17 mpgs. She got ten when I bought her, so she's come a long way since then. She costs close to nothing to fix since shes so old and reliability is awesome, never broke down on me yet. I would like to get better mpg's out of that 205,000 mile chevy v8. Where should I start? Nothing that makes it look ridiculous. And cheap stuff for now, Im only making 100$ a week until summer. Thanks guys and I look forward to being a active member on this forum.

[Christ]

Start with cheap/free mods:

Inflate your tires.
Check that brakes aren't dragging.
Alignment.
Remove pass side mirror if you don't need it.
Driver training.
Driver training.
Driver training.
Try grille block.
Make some ducting so that any air that gets through the grille HAS to go through the radiator.
Driver training.
DRIVER TRAINING.

[cleanspeed1]

Originally Posted by Christ

Start with cheap/free mods:

Inflate your tires.
Check that brakes aren't dragging.
Alignment.
Remove pass side mirror if you don't need it.
Driver training.
Driver training.
Driver training.
Try grille block.
Make some ducting so that any air that gets through the grille HAS to go through the radiator.
Driver training.
DRIVER TRAINING.

+1 with a bullet.

Go to fellow member "aerohead" and see what he did with his pickups.

If you are not hauling heavy, I'd lower the truck front and rear ( set of used springs and lowering blocks ), make a cheap belly pan, smooth hubcaps, get a Scangauge and learn to drive by it; if the bed is open, get a cap or cover;
make sure all your emission controls are functioning properly ( w/205k, make sure catalytic convertor isn't clogged, O2 sensor (s) have been replaced, etc. ).

[Incienso]

I can't offer any advice since I'm new to this my self, but good luck! I know how it feels, I'm a college student on a budget.

[Frank Lee]

First of all, put the real tailgate back on. And leave it up.

Then put a tonneau over the box if you don't use it all the time. Or if you are ambitious, an aerocap. Or if you don't like the looks of that, a regular cap.

P.S. Even a 1/2 tonneau is claimed to be effective at reducing aero drag. Search it here.

Third, it will need a gear-up to get better mileage. Best way would be to convert to a manual transmission, but if that is more than you care to take on I think a different rear axle with higher (lower numerically) gears would help.

I've done a fan delete on mine. Even though I've not quantified the effect, it would be similar to what people have gotten going from mechanical fan to electric fan. I really like the fan delete mod. The engine is so much quieter.

Run it down to less than 1/4 tank and then FILL IT when you go to the gas station- that will help with the gaslog and mileage calculations and reduce time wasted running in for gas... unless you are like the boys around here, that are at the gas station several times a day anyway.

After that, do the things listed in the 65 mods as you see fit.

[Ryland]

I realize that you said you've done alot of work to this vehicle, but how much do you need it? could you sell it for enough to buy a more practical vehicle that gets better mileage and is most likely going to cost you less to keep on the road?
Otherwise, like others have said, Belly pan and tire pressure are good places to start, make sure that the mods you are making help, like the cold air intake and throttle spacing, do they really help?
Another way to look at it is to figure out how much you spend on fuel and budget that amount out, saving any extra instead of spending it.

[1990 GMC gas hog]

The cold air intake and throttle body do help they've increased my gas mileage by 2 if i drive like a granny. I can't get rid of my truck I love her too much. Anyways Frank what is better a tonneau or a regular cap? I can get a cap for mine 150$ but not sure if it fits, my truck has the stepside, or I can get a tonno for 250$.

[1990 GMC gas hog]

Oh and I have all after-market exhaust and I can find a scan gauge for my truck since she's 21 years old.

[1990 GMC gas hog]

I mean can't find a scan gauge. Can't find one for vehicles under 96

[Christ]

Originally Posted by 1990 GMC gas hog

The cold air intake and throttle body do help they've increased my gas mileage by 2 if i drive like a granny.

I don't need to point this out to anyone here, except I thought the OP could learn something from it.

1. You pointed out a few different things -in the same sentence- that could have had an effect on your fuel economy.

2. I, and many others, doubt you got a 10%+ gain from a CAI and throttle body mod.

3. Even if you did, you haven't measured, or shown measures, of accurately calculated mileage figures.