loss of MPGs after valve adjustment???

[LB72004]

Update,

the last few fill ups where all around 320~350 Miles to a tank, dont remember the number of gallons, but it was no better then before. one trip was almost all highway miles and it was almost 430 miles. that sucks. it used to get right at 600 miles to a tank on highway only.

then, what are the odds, one of the injectors shorted out. so i ended up having to tear into it and replace #5. i decided that while i was in there i might as well adjust the valve lash back to stock.

now we wait and see if there is any improvement.

[hecatti]

Hi! Any update on this?

[LB72004]

i am only about a hundred miles into my first tank after the adjustment. i will post any updates here

[LB72004]

First tank after valve adjustment.

404.6 miles, 24.282 gal - 16.66 mpg

only about 30 miles total highway, rest are all stop and go/city

best tank so far since the initial adjustment. 16ish mpgs is where I used to be at in town so it is looking promising.

[LB72004]

449.1 miles, 25.273 gal - 17.769 MPGs

of curse this was with about 180 miles highway, rest with stop and go and back country roads. i am liking it so far. a few more like this and i am convinced that valve adjustment plays a big roll in MPGs

[LB72004]

PS this is with the 2nd CP3 back on

[minytrker]

449.1 miles, 25.273 gal - 17.769 MPGs

of curse this was with about 180 miles highway, rest with stop and go and back country roads. i am liking it so far. a few more like this and i am convinced that valve adjustment plays a big roll in MPGs

Thats about where my highway mileage is up to now after 6-7,000 miles on the injectors. Im still getting 14-16mpg around town though. Its slowly getting better, but I still like the way trucks runs and how quite it is compared to before. Also quit burning oil and its only tan now at 5,000 miles when I change it vs black after few hundred miles.

[minytrker]

PS this is with the 2nd CP3 back on

How do you like it? Im been debating buying one.

[andrewjamesbond1]

This is awesome to hear! Good data with known constants and variables!

[LB72004]

How do you like it? Im been debating buying one.

i like it, of course mine is home brew with an Ebay CP3. i built the bracket and assembled the lines myself so i put no more then about $350 into it. the primary CP3 was getting weak. when i started having trouble with my injectors and i couldn't build enough pressure to start the engine i decided to put the extra pump to use. i was then able to start it and drive it for a couple of weeks till i got new injectors. after the injectors where put in i decided to keep it on.

when i removed it for this MPG test i found that the throttle response seemed a bit slower, i think i got used to the "have pressure when you need it" ability and my weak CP3 couldn't satisfy me anymore.

unless you are planing on having larger injectors and a turbo upgrade, along with some internal work if you turn it up, you wont see much of any gain. if you can maintain 21+K PSI at WOT it would not even bother. the problem is more along the lines of keeping yourself in check and not turning up the pulse width too much and destroying your engine.

i only run 2200 PW and command 190 Mpa (makes around 180 Mpa) at WOT.

one aspect that i do love is the ability to start the engine even if i run the batteries down and it is turning over real slow. its ability to build pressure is amazing.

overall i think it was well worth it at $350 i spent to put it together