So is it a selling ploy or can you improve gas mileage by adding a bored out TB? Improved mileage is one of the claims by some sellers, but it seems to me that you will be burning more gas, not less. Also - add into the mix an FIPK such as the K&N.
Looking at one off ebay or even here, plus I have a K&N FIPK that's been sitting in the garage for about a year - never used since I got it. Should I pull the trigger on the TB?

 

I've seen claims of mpg increases from .5-2 mpg with the modified stock TBs but the #1 factor in increasing mpg is learning how to CONTROL YOUR RIGHT FOOT on the skinny pedal. Once you install the modified TB you have a tendency to 'play' with the increased performance. Check with one of our members 1999blkdakrt (Brian) about one. I don't know if he's back home yet because he had to go to Washington state last week for his Dad's funeral. May he RIP.

Now let me give you my take on CAI and I know I'm probably going to get ripped for this but here goes. CAI's do not increase mpg but decreases it. Increases performance yes...mpg no. When the IAT sensor in the manifold sees the colder incoming air it tells the PCM to richen up the fuel mixture somewhat which causes you to burn more fuel thus decreasing your mpg. You'll actually have a lot better chance of increasing mpg if you use a round air breather setup because it takes in the warmer air and the IAT sensor will tell the PCM to lean out the fuel mixture somewhat. I've had the K&N FIPK on my '01 Dakota R/T and really didn't find it to be worth all the hype about increased mpg and hp. I've been running a round air breather setup for 6 years now and getting 16.5/19 mpg with enough power to roast the rear tires anytime I want to.

A little tip for removing a lot of the engine bay heat...remove the piece of weather stripping along the front edge of the wiper cowl that seals up against the back edge of the hood. You will be amazed how much hot air will go out that open space you just created and it will not create a water problem in the engine bay when it rains or when you wash your truck.

 

Hey, thanks for a good explanation. I'll def look into the rubber around the cowl. I hope others chime in about this as well.

funny sig ...

 

bored tb will increase the flow through the system, and make the engine work less to get air in (think of the engine as an air pump some of the power created is used to pull in fresh air make this part easier and you will improve efficiency). It will also increase the power available at a given throttle position(this and the computer detecting colder air), because of this there is the POTENTIAL to improve fuel economy, however i agree with bwdakrt that in most cases it will actually hurt fuel economy because most people go 'cool more power, lets use it!!!!' and this causes a DECREASE in fuel efficiency. As stated if you can install the CAI and the bored TB and actaully have the self control to keep your foot out of the gas you can realize some minor mpg improvement, it will not be anything huge tho.

 

Never pictured myself before being overly concerned with gas mileage, but it's time for me to wake up & realize that it's the wise thing to do. Understand that getting a little "car" is not an option - the Durango is perfect for my needs, plus I have no payments.

So let's assume that I do have the restraint & control to caress the skinny pedal. It is, after all an SUV with a gas-hungry motor. Plus it's Premium fuel only. So which makes more sense for gas mileage control: 1) Using the TB without the CAI versus 2) Using them both versus 3) using neither & continue stock. Mind you, I already have 1 of the the add-ons in hand.

Thanks

 

the best thing for mpgs if you can keep your foot out of it is to suck in warm air, this will lean out the fuel mixture and burn less gas, as stated the round filter which would bolt directly onto the TB would be the best for this case.

 

Would that round filter negate the stock air hat intake or they work hand-in-hand? I'm guessing that by "round filter" you mean something like those found in certain older vehicles? And do you mean that with the stock TB or even a bored one? A picture of that set-up would help me to understand better.

Forgive me if my ignorance is showing. My purpose for asking all these questions is to learn. I'm kinda stuck with the D now, having freshly lost my job (besides I love the truck) and I am exploring any and all options I can think of to save some pennies.

 

You can remove the air redirector cowl and let the airbox just suck in the hot air under the hood.

 

I can tell you from my experience, the fastman 52mm throttle body, OEM K&N air filter and custom ram air intake did not make any difference if not lessen my mpg but only by a small amount. I used to avg around 11.5 in town during the summer (have to run a/c full time) but now getting almost 10.5 in town.

Highway seems to be unaffected around 13-14 mpg.

I do enjoy the extra boost in power from this combo.

Now that I have the new Hughes F1 airgap and SCT tuner, on street mode(87 oct), I do see mpg improvement. I am now holding almost 12 mpg in town. But have yet to see what improvement my highway mpg would be since I haven't had a chance to make a long road trip.

 

I'll take the 2 mpg around town. Better than the 10 I'm getting! But she still needs Premium only and I'm doing research on how to get her to run well on Regular. IIRC I think someone told me that I'll need a tuner, but I'm not sure. If that is the case then I'm doomed to 91+ because a Tuner is def. not in the budget at this time.

Well I'll take all the info offered here under advisement. Good stuff. BTW, how reliable is the OHC information center with respect to mpg?

Thx guys