1996 Silverado K1500 Fresh Meat

[vteco]

1996 Silverado K1500, extended cab, 5.0 liter, 230 hp, regular bed, .45 Cd, 28 sqft.

Nothing has been done to it yet.

Scratching head.....

[aerohead]

If the Chevy is your daily driver, and a significant portion of your mileage is at highway speed, here's some 'no-brainer' mods by GM.
You'd have to decide about the bed cover vs ease of cargo carrying.
We can go from there.https://ecomodder.com/forum/member-a...mendations.jpg

[vteco]

@aerohead it is my daily driver (though I don't drive every day).

No, highway mileage is a small proportion. Rural hilly to mountainous curvy driving is its main fare at 35-45 mph generally with occasional half hour 50-55 mph trips. Very few stop lights or stop signs, on the positive side. It's not city driving in any sense.

That doesn't mean I don't want to optimize it anyway for a rare longer highway trip. And a better shape can't hurt mileage at slower speeds. I'll treat it as fun and educational.

Instrumentation/driving will be important to best mpg in my circumstance. Energy planning. But I'm also interested in what can be done by possibly working with tuning and transmission.

I think it's an interesting circumstance to explore.

[aerohead]

Originally Posted by vteco

@aerohead it is my daily driver (though I don't drive every day).

No, highway mileage is a small proportion. Rural hilly to mountainous curvy driving is its main fare at 35-45 mph generally with occasional half hour 50-55 mph trips. Very few stop lights or stop signs, on the positive side. It's not city driving in any sense.

That doesn't mean I don't want to optimize it anyway for a rare longer highway trip. And a better shape can't hurt mileage at slower speeds. I'll treat it as fun and educational.

Instrumentation/driving will be important to best mpg in my circumstance. Energy planning. But I'm also interested in what can be done by possibly working with tuning and transmission.

I think it's an interesting circumstance to explore.

1) If the EFI, electronic spark control, and all the sensors are operating to OEM specs, I'm unsure if you'd find any 'fruit' there.
2) A full-synthetic engine oil, transmission, and rear axle lube package is 'where GM went to', get to today's efficiencies. You just want to respect any known limitations if you transition to different liquids.
3) Electric, Messier water pump, and electric radiator cooling fan? The Caprice, Roadmaster, DeVille 350 small-blocks had some of this.
4) The transmission itself, I don't know. GMC/Chevrolet/Ford are up to 10-speeds today. You should have a 4-Speed, electric lock-up overdrive. Best mpg for the engine is at the engine's maximum-rated torque RPM. A good tachometer would help inform 'where you are'.
5) Knowing what the engine /gearing is doing right now, might help decide of a different ring-and pinion, or Gear Vendors electric overdrive could be in the mix.
6) I'm running 44-psi, Hankook, H speed-rated tires instead of LT tires. I watch my loads. Maybe not an option for you.
7) If you get the aero right, any weight gains will be more than cancelled.
If you don't tow a bunch, 'passenger car' mirrors are an immediate drag reduction. Lower drag means less cooling, so some radiator blocking is easily accommodated.

[vteco]

Well so just out of curiosity I wrote to Black Bear Performance to get their take on whether an ECM could be "tuned" for fuel economy, not increased HP or torque, in the above driving scenario on this particular vehicle. They have a good rep with GMT400 people, and I'm pretty sure they'd say "No" if this is not reasonably improved through anything they can do.

[vteco]

Received a call from Black Bear Performance. The guy at the other end didn't seem to understand what I was asking. He basically reiterated what the website said about custom tuning through them -- gains in HP and torque but at most only slight gain in fuel economy.

I said I wasn't interested in HP gain or torque gain per se, I didn't tow heavy loads in summer, didn't do long distances at highway speeds in general, etc. That I was ONLY interested in a custom tune that might increase fuel economy at say an average 40 mph rural driving -- if that was possible. Would shift points be adjusted, etc.?

He just reiterated what he said were the benefits. From that I gathered that it wouldn't be a "custom" tune to favor a set of desired parameters, but probably just a flash of stock firmware. Or maybe he was just a phone salesman and didn't understand what might be possible for the back shop to do. I do know they do true custom performance tunes, and even loan out recording engine monitors to gather data to optimize custom tunes.

Well shucks, anyway, no progress on that front. Too bad.

[freebeard]

"Or maybe he was just a phone salesman and..." was sweating bullets about losing his seat.

[vteco]

He just didn't get it. Probably unaware that you could actually tune for economy in any way.

I think a manufacturer sets up an ECU profile to provide performance compromises that align with general popular expectations. Ads show 4WD pickup trucks doing rock climbing, and towing big loads. People want trucks fast off the line. Images of power are the norm. That's the selling point.

I do believe that alternative custom ECU program compromises could be biased towards fuel economy if one were willing to give up some performance, likewise. Do I really need 260 hp in my truck? For the driving I normally do? I don't think so. Would topping out at 220 be okay? Probably. Would I even notice the difference for my uses?

I think tuning for economy isn't an imaginary goal.

[vteco]

Well, biting the bullet rather hard, but I'm interested in the subject. Sent for an ECM programmer for the Silverado.

This isn't aerodynamics, so I'll continue in another section of the forum for this particular mod.

[me and my metro]

There are lots of little things that add up. Temperature trickers, get it started then tell it that it is warm and in warm air. Instantly leans out. Never use cruise control! Reprogram the transmission to shift and lockup early. Hold in the highest gear while locked up. You might even put a “short” cam in it to loose some horsepower. 40 years ago they sold economy cams that had smaller profiles than stock cams. Kind of like pulling the 350 and putting in a 305.