IRoss

I haven't really had a chance to get a exact reading with a gauge, but the pump is pretty much to the head, my injectors have recently been tested and cleaned and are 'perfect', my smoke screw and starwheel are all the way up, and my pump has been de-tuned to the point of being a dog...still only getting 18mpg, down from about 22mpg about a year ago...ive added a bhak since then also....as well, despite the fuel screws being backed out there is still a black cloud as the turbo spools....the truck is still fairly responsive, it certainly doesn't feel as if the timing is retarded, does this sound like an advance piston issue to anyone? I know my IC leaks a bit but it will still hold 24psi at 900F (post-turbo)...thanx

NotEnufGarage

Try backing it off 1/16th" and see if it improves. Also, try an additive that adds Cetane and see if that helps.

93beater

ya im curious about that too, im not aware of the condish of my injectors due to insufficient funds, but my pump is turned up i have 33in tires 354 gears k&n open box and quite a bit of timing and my milegae is only about 16-17 highway like 13-15 in town what can help me with this problem?

Crossy's son

Wider tires really drop mileage, my dad figured out with his 05 dodge CTD that he lost 2 mpg on highway.

Rampage1967

To much timing killed my mileage.
Backed it down & mileage returned.

Stihl

33's aren't that big comparatively though, it shouldn't make that much of a difference. With 35" bfg all terrains I get about 14 mpg .. with 39.5x18" Boggers on 16.5x14 welds I get like 13.5

IRoss

I've always run bfg 33's and never noticed much of a difference in mileage over their lifespan (when they are down to the wear bars they measure about 31.5") Before I started messing with the truck it would get 24mpg with new muds so I guess I'll try backing the timing off a bit to see if that helps...keep you posted..

gear jammer 91"

If you have the fuel screw backed out too far, it could actually hurt your mileage by not having enough pressure at the injectors to atomize the fuel properly. Turning it in a 1/4 turn might be worth a try.

89f150

with 35's got over 17

IRoss

yah, I just started turning the fuel screw back in a little bit, partly to bump the idle a little bit since its gettin cold out, so we'll see if that makes a diiference...I also just ordered the timing tool (only 53 bucks) so I'll actually get to see how far advanced it is....

tcs 91

what kind of a timing tool did you order ? if you don't mind. mechanical or a timing lt?

IRoss

So I finally got around to using my dial gauge, and wow, I was getting measurements of around .084"(almost 2.2mm)..Is this possible? I thought I read that the advance limit in the VE was roughly 2.0mm(20deg?)..Previously, I checked my tdc using a dial indicator so I know thats accurate. I was following the timing procedure in the sticky (thanx wanna) How far back does the crank have to be turned before the needle on the DI 'stops moving', is it just a number of degrees or is it more?

jcmoyer2004

and how do you know how far to move the pump, i'm planning on cranking my fuel screw in and putting on a 60mm wheel and a 14cm housing. I want it to wake up and run, but dont want to kill my mileage. any ideas on how far to bump the pump over.

wannadiesel

Depends on how far the timing is advanced. You have to get the rollers off the ramps on the cam plate.

wannadiesel

A 1/8" bump works pretty well with stock injectors.