Soo, in everyone's opinion, what is the best modification for improving gas mileage. I was thinking the air filter, but what do yall think?

 

Plain and simple, there is no modification that will increase MPG.

I know people are going to flame me for that but I have tried just about every box, programmer, one set of injectors, air modifications of just about every design, straight pipe, 4" exhaust, reducing aerodynamic add ons, etc. etc. Some say they have increased MPG with certain bombs but I think most are just trying to justify the money they just spent by saying they have increased MPG. Then again it is a good marketing tool too, if you buy a product and it increases your hp but not the claimed mileage most are happy and don't send the product back.

The only thing that I have found that will increase MPG is tire inflation and slowing down, even those are marginal.

 

no flames intended with this comment. the best mileage the original owner ever got on road with my 90 ctd was 19. he wouldnt let me touch the seals on the pump. i have owned the truck since 95. the only high dollar mod has been intercooler . i have turned every screw on the pump to the rich side. added hx35. best so far is 21.1 at 70 mph empty. all mileage checked with a gps. the ctd is the only engine that i have ever modifyed that mileage didnt go in the toilet. no noticeable change with the intercooler. i have yet to find a show room diesel pickup to out run me, any brand.

 

Best mpg improving mod to do on a 12 valve is to kick the timing up to 15.5- 16.5.
If your plate is pushed all the way forward back it off about 1/16".
If you are in stop and go put the star wheel back in the middle. If it's mostly highway driving you do leave it be.
Biggest fuel conserving mod is to put an egg in-between the go pedal and your foot.

 

OOPS. I was responding for a 24 valve. I should have read your signature better.

 

I would have to agree with infidel on my 94 4x4 with 4:10 gears timed at 17* i picked up 1.8 mpg running at 60 and that is with 300hp injectors + boost elbow other than that stock(except the kitty ran away from home have you seen him ?????). The timing really perks them up!

 

I know that a real tight Auto tranny will up your MPG, I know this because it gave me better MPG. 200 mile trip to get Tim to rebuild my tranny with DTT parts, got 14.7 on the way up and 20.56 on the way home.
If you need a rebuild, get up with Tim he will save you money on diesel.

CRIS

 

Cris,

Thanks for the tranny info on improving your mileage.

How is it doing now in daily driving ?

I'm heading for a timing boost this weekend myself.

The other mod we talked about will come the first of next month.

Wayne

 

I would say timing, intake and exhaust.

I can get better milage than I was stock depending on how I am driving.

 

Advanced cam timing and a larger turbo exhaust housing also, but both have negative effects. The cam timing works on gas and diesel vehicles but adds more NOX. That is why it is retarded for EPA standards. Advancing the timing lowers the power band to where it is more in line with the normal driving insead of wound out.

 

Hmm, mine gets less mileage now than it did "Pre-Tim".. Might have something to do with the power he added while my truck was in his capable hands - well, it's really more because I'm ENJOYING the power!

Tim Barber is most certainly the MAN!

 

No timing done here but I do have exhaust and intake, I got 17.6 mpg through the mountains and I have 4.10's and 4X4. Thing was I kept it below 65 mph.