before i bomb

[jlast]

I am wanting to know how to go about figuring out what I have done to my truck before going about bombing.



I was told stock trucks have around 13 - 15 psi of boost, and mine is 24 - 25 psi, checked on two different gauges.



Stock h1c with 18. 5 housing,

appear stock pump, all the safety tabs, screw cover, etc...

can still fit my finger sideways next to head and pump,



3. 5" exhaust all the way, and a huge green filter, are the only mods i have done.



I do not want to change something and lose hp, but would like to know where the extra power is coming from?



I am mechanically inclined so anything i need to do i can, but not 100% sure where to start.





also a somewhat related, i only get around 15 mpg unloaded city or highway. I dont notice alot of excess smoke, only the puff when i step on her. best i think was 17mpg. This is no matter how i drive, i tried easy route blocking the accel. so i couldnt get full pedal and took a easy, and unblocked.



I know that my lack of mileage might be why i am alittle low on mpg but it sounds like a am really low?



currently on 215/85r16, but going to 255/85r16 soon to also help on the mpg.

 

[Bob Beauchaine]

Well for starters your exhaust is not stock so that's a plus. The big green filter sounds like a "Green High Performance" air filter. This filter was developed for the Paris to Dakar off road race and flows more air than the K&N - it is also as efficient. I have run one for about 10,000 miles and my intake hose is still clean. In addition my oil analysis shows 2 parts per million of silica (dirt) which is unchanged from OEM and K&N numbers.



From your MPG numbers it sounds as if you are running 4. 10 gears in the rear diff. I am running 3. 54 and I run 17 MPG city and 22 highway. Hope this helps



Bob

 

[jlast]

Yes on the green filter, and agree on the exhaust that is why I did both those mods myself, and completly made the exhaust from turbo back. But in no way should just those two mods should I be getting 25 PSI? if so i might have to sell my own stuff for some profits



Looking for suggestions, things to look at, should I pull injector to see what numbers there is, etc... . I need to know where this power comes from before i undo it.



agree on the mileage if i was 4. 10, but i am 3. 54!!!!!



so good power, low mpg, and the 17mpg was all highway for the highest mpg i have gotten so far. i have yet to get any higher mpg.



talk to me,



BOB got any pics of your filter setup and mounting? i got mine but dont like the way it is currently setup, looking to change it.

also how much psi do you see?

 

[RGT]

your mileage does sound low I average 21. 5 around town and highway... I would think the wider tires, even if a little taller, would only lower your mpg's... .

 

[nascar mark]

Sounds like the engine still has stoke inj's but someone has been in the pump before and has put the tamper caps back on. Easy to do if you are carefull.

 

[Bob Beauchaine]

There is a number visible on your injectors without pulling them. It is on the exposed part just above the hold down nut - it's a 4 digit number. See what that number is and let me know - maybe we can see if its stock or not.



Bob

 

[jlast]

off of injectors



8965

kdal59r#

# is a number but couldnt see exactly what it was looks like a 6, 8, 9.



Rgt going from a 30" to a 33" to help with the rpm range during driving, especally at interstate speed. not worried about wide tires other then to fit on the dually, just needed height for mpg plus fill wheel openings with the lift.



been in the pump before, doable. I highly doubt it as the truck came for a privately owned company as their work truck and had many other trucks also, i would think reliablitiy would be what they were after. Only way to find out is to dive into the pump, but have to wait till after winter.



Dont have a clue why mpg is so bad? any suggestions?

 

[Greenleaf]

MPG/Boost PSI

Last I checked, I was at 24. 8 mpg. My truck is running 245/75-16's. Have 3. 54 diff. Auto, not much in the way of mods to engine.



It is currently in the shop undergoing a metamorphosis. Lots of mods/tweaks/changes etc. etc. I had to know where I stand with the modes/tweaks thus far so I get things buttoned up enough to take a test drive.



I'll say this much; don't have near 25psi boost [yet].



Scott

 

[JLEONARD]

I get 22/24 mpg daily, and 26+ on a trip. I usually drive at 70 + when I can.

I have 3. 54s and 235/85 - 16 tires.

I got 24 psi boost when I first got the truck it was stock.

Now I get 27/28 psi with the 16 cm housing and the fuel pin rotated to max.

Note no intercooler so no pressure loss there, and hotter air entering the manifold.

 

[Bob Beauchaine]

JLast

Those are your stock Bosch injector numbers.



Bob

 

[jlast]

Thank you bob for the injector info, got one item identified.





YOU ARE KILLING ME with those mpg numbers. I know i got the biggest factory 1st gen diesel tank but i am at least 5mpg to almost 10 mpg less then most of you.



NEED mpg help? suggestions?