Fuel mileage help with add-ons?
#2
I added air to my tires, does that count?
I hear that Vortex/Turbinator intake spacer thing is worthless, but you can buy it anyway if you want (it's your truck!). The only things I can think of that would help mpg might be the "cold air" intake mod, a cat back exhaust and pcm4less tune to optimize power delivery so you don't need to push as hard on the skinny pedal. Oh yeah, stay with the stock wheels and base 32" tires in a street oriented design for best mpg. Look up the individual tire weights to find a lighter tire to help reduce rotational losses. The stock wheels are 22lbs if I remember correctly and about the lightest I have found, going to an 18/20/22" rim can add up to 25% in weight and those cool MTZ's aren't the lightest tire either.
I hear that Vortex/Turbinator intake spacer thing is worthless, but you can buy it anyway if you want (it's your truck!). The only things I can think of that would help mpg might be the "cold air" intake mod, a cat back exhaust and pcm4less tune to optimize power delivery so you don't need to push as hard on the skinny pedal. Oh yeah, stay with the stock wheels and base 32" tires in a street oriented design for best mpg. Look up the individual tire weights to find a lighter tire to help reduce rotational losses. The stock wheels are 22lbs if I remember correctly and about the lightest I have found, going to an 18/20/22" rim can add up to 25% in weight and those cool MTZ's aren't the lightest tire either.
#3
RSC made some great suggestions. My Magnaflow catback has to be helping add a wee bit more mpg plus it makes the I5 sound a little less wimpy.
I'll add that switching all the fluids to 100% synthetic has been the single thing that has made the most noticable difference in mine. I use Amsoil but I think any 100% syn would acheive the same results. Also might want to look into an AirDoc. It eliminates restrictive airflow between the stock filter box and the throttle body. (cold air intake systems) Putting in a less restrictive air filter like a K&N will also help a bit but the downside to that is it lets more dirt particles enter your engine then say a stock AC Delco filter would. If your going ***** out and are going for the money to retune the PCM, pcmforless has an electric fan swap in kit as well. Eliminating the fan clutch and the fan should free up some stress on your motor. (PCMforless.com)
Keep us updated and let us know what you end up doing.
I'll add that switching all the fluids to 100% synthetic has been the single thing that has made the most noticable difference in mine. I use Amsoil but I think any 100% syn would acheive the same results. Also might want to look into an AirDoc. It eliminates restrictive airflow between the stock filter box and the throttle body. (cold air intake systems) Putting in a less restrictive air filter like a K&N will also help a bit but the downside to that is it lets more dirt particles enter your engine then say a stock AC Delco filter would. If your going ***** out and are going for the money to retune the PCM, pcmforless has an electric fan swap in kit as well. Eliminating the fan clutch and the fan should free up some stress on your motor. (PCMforless.com)
Keep us updated and let us know what you end up doing.
#5
The easiest and cheapest resulting in improved gas mileage, keep your throttle body clean. I have added an Air Doc (OEM paper filter), GM Performance exhaust, and I clean my throttle body every oil change and I'm getting 18 mpg (scan guage II)...even better on long highway road trips.
#6
RSC made some great suggestions. My Magnaflow catback has to be helping add a wee bit more mpg plus it makes the I5 sound a little less wimpy.
I'll add that switching all the fluids to 100% synthetic has been the single thing that has made the most noticable difference in mine. I use Amsoil but I think any 100% syn would acheive the same results. Also might want to look into an AirDoc. It eliminates restrictive airflow between the stock filter box and the throttle body. (cold air intake systems) Putting in a less restrictive air filter like a K&N will also help a bit but the downside to that is it lets more dirt particles enter your engine then say a stock AC Delco filter would. If your going ***** out and are going for the money to retune the PCM, pcmforless has an electric fan swap in kit as well. Eliminating the fan clutch and the fan should free up some stress on your motor. (PCMforless.com)
Keep us updated and let us know what you end up doing.
I'll add that switching all the fluids to 100% synthetic has been the single thing that has made the most noticable difference in mine. I use Amsoil but I think any 100% syn would acheive the same results. Also might want to look into an AirDoc. It eliminates restrictive airflow between the stock filter box and the throttle body. (cold air intake systems) Putting in a less restrictive air filter like a K&N will also help a bit but the downside to that is it lets more dirt particles enter your engine then say a stock AC Delco filter would. If your going ***** out and are going for the money to retune the PCM, pcmforless has an electric fan swap in kit as well. Eliminating the fan clutch and the fan should free up some stress on your motor. (PCMforless.com)
Keep us updated and let us know what you end up doing.
#10
CAI's help on engines that dont use a throttle plate, like some diesel engines, however.....
Reducing the restriction (and thus the vacuum pulled) between the air filter and the throttle plate will not help your mpg, simply for the fact that this does nothing to reduce the restriction/vacuum between the throttle plate and the rest of the intake. CAI's will only help when the throttle plate is significantly open (close to full throttle) such that the entire intake tract will see the benefit of reduced restriction, which reduces the work required by the engine and also increases flow.
At partial throttle like highway driving the actual vacuum that then engine sees (between the throttle plate and the combustion chamber is not changed by any CAI or high flow air filter, and therefore no mpg benefit is realized.
The best ways to realize better mpg are to find real ways to make the engine work less, or to optimize the fuel trims by leaning out the partial throttle trims a bit. Even then, like someone mentioned above, the investment required to make significant improvements can cost more than the savings in gas. Experimenting with different tires, switching to all synthetic fluids, computer programming modules like the scangauge, etc all add up quickly and could take years to break even allowing for just a few mpg improvement. You are better off looking to trade in your hummer for a more fuel efficient vehicle.
Reducing the restriction (and thus the vacuum pulled) between the air filter and the throttle plate will not help your mpg, simply for the fact that this does nothing to reduce the restriction/vacuum between the throttle plate and the rest of the intake. CAI's will only help when the throttle plate is significantly open (close to full throttle) such that the entire intake tract will see the benefit of reduced restriction, which reduces the work required by the engine and also increases flow.
At partial throttle like highway driving the actual vacuum that then engine sees (between the throttle plate and the combustion chamber is not changed by any CAI or high flow air filter, and therefore no mpg benefit is realized.
The best ways to realize better mpg are to find real ways to make the engine work less, or to optimize the fuel trims by leaning out the partial throttle trims a bit. Even then, like someone mentioned above, the investment required to make significant improvements can cost more than the savings in gas. Experimenting with different tires, switching to all synthetic fluids, computer programming modules like the scangauge, etc all add up quickly and could take years to break even allowing for just a few mpg improvement. You are better off looking to trade in your hummer for a more fuel efficient vehicle.