Hey guys, I have a 2000 dakota with the 3.9L V6 in it, only 70,000 miles on it. recently I decided to spend some money to get a bit more power and a little better gas mileage. So I got a V8 throttle body, CAI, dynomax superturbo exhaust, new spark plugs, and a superchips tuner. It definitely has more power, but my gas mileage has goen down. Before the mods I was getting about 16-16.5 mpg with normal driving, and if I ran through a whole tank on the highway on cruise I would get around 19 mpg. Now I am getting around 14.5 around town, and I just made a trip on the same highway as always on cruise the whole way, and only got 17 mpg out of it. My tires are blown up, I run injector cleaner through my engine about every two months, and I just did that the week before I made the changes, so I know that's not the problem. I haven't changed the way I drive (everyone says I drive like an old lady). Everyone told me these mods wouldn't decrease my gas mileage, if anything they should increase it a little. Has anyone else had this happen? Thanks for any input.

 

one or 2 mods like that will probly help milage but all together you start making more power and mileage heads south, happens, its a trade off really,
if you want your milage back youre gonna have to take some mods off

 

Yeah, I was thinking that. I would really like to keep the power and at least get the mileage I had before. I have an underdrive pulley setup coming soon, maybe that will get me a little closer to the mileage I used to get.

 

its probably your superchip. around town tune it to the gas saver and when you go out in the highway reflash it to preformance.

 

qft!!

 

a UDP will not help mpg.

 

It won't hurt it any, and in theroy should help. Maybe not a noticable amount but less friction = better mpg. Just a matter of whether it is noticable or not..

 

udp??

 

In theory it should help a little, the same way that making a vehicle more aerodynamic will help gas mileage.

 

If you want performance, kiss fuel mileage goodbye. It's as simple as that. It's a trade off, just like batman said.