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Discussion Starter #1 (Edited)
How does inj pump mod affect MPG

Of course I want more power when I NEED it but just driving around town normally would this modifiction decrease my MPG?
 

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Which pump are you referring to? If its the injector pump, not sure what the change in MPG would be. If your talking about a lift pump, my fass yielded EXACTLY the same MPG in all circumstances, with a little bit of horsepower gain. The lift pump wont negatively affect MPG because the fuel not being used by the injector pump will be returned to the tank. My city/highway before and after the lift pump was 15.0/16.4 and 15.0/16.5 in the same driving conditions. Some people are reporting a mileage increase using the aftermarket lift pump, but that's just not true for me.
 

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Turning up the fuel screw will give you better fuel efficiency, because it increases injection pressure.

Theoretically, anyways.

Theoretically it also cuts life expectancy of the pump in half... Hmm....

But who cares about the $800 injection pump anymore when it costs $150 to fill up your tank? :CRY:

Fuel prices really put stuff in perspective... :CRY: :CRY: :CRY:
 

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Discussion Starter #4
Im talking about The VE injector pump mod everone does by turning the fuel adjustment screw up. I deff dont want to lose MPG under normal conditions

Begle1:
Thats the first time I heard of it cuts your injector pump life in half???
 

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The VE pump doesn't like high internal pressures. There have been people that have turned up a high milage pump and had it die in a short period of time. Each pump is different. So your milage might vary on pump life.
 

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Philip,
If you run big sticks does it relieve some of the higher pressure's on the turned up pump?
 

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If you run big sticks does it relieve some of the higher pressure's on the turned up pump?
It might drop pressure some due to larger tip sizes. How much I don't know.

Most of the sites I hang around the failures we see are people with stock or small injectors and the screws near runaway settings. The people with the bigger sticks don't see to much pump problems. They have to run less fuel screw to controll EGT problems.

My thoughts on injectors. Buy big the first time. Use the pump setting for final adjust for your needs. A pump can be turned down. :lol3:

Look at the injectors in my sig. With stock pump settings these put out the same power as a set of POD's with the fuel screw all the way in. Plus I have room for improvement with the turn of a screw. :D
 

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what brand injectors are those there philip or are they a custom set??
 

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Those are EDM's. Any injection shop should be abel to order you a set of whatever size you want. I wouldn't recommend over 6X.016"s. There was HP lost by going to .018" over the .016" in conclusive testing on a High HP VE truck.
 

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is that just the nozzle or the entire injector, what do you do give them the bosch PN and they order you a correct set
 

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Conclusive, eh?

Conclusivity on the Internet... :lol3: :rof

Bigger injectors would have to result in a drop in pump pressure. It can be seen clearly on common rail trucks that run rail pressure gauges. I don't see why we'd be any different.
 

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yea it makes perfect sense as its the law of fluids under pressure, less restriction equals less pressure, still dosent answer my question on Philip's sticks though

anyone have a FP gauge on their truck and can give a pressure reading with stock vs. tweaked pump vs. injectors

i know the VE's dont like anything over 25 PSI so a 2nd gen LP will be to much for them but with a return style regulator tuned to run a constant 15 PSI should be perfect for any mod that basic bolt ons will go to, problem is finding a cheap return style regulator that works with diesel!
 

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My injectors were made by New Era Diesel. I got them second hand. They only had a couple thousand miles on them. If that much.

With my stock pump settings at WOT I carry 4 PSI on fuel pressure. Thats running out to around 90 MPH. I don't want a ticket on my CDL's so I haven't pushed it higher.

I'll might be able to give an after reading if I need to turn it up to spool the HX40 when I install it. That will not be to long in the future. I have the modded 3" IC in. The truck is down waiting on a power steering hose. :(
 

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Conclusive, eh?

Conclusivity on the Internet... :lol3: :rof

QUOTE]

What reasoning would KTA have to lie about his results? Besides, Swank and him both made 600+ with 6X.016 injectors. Volume makes HP but without atomization you have nothing. Go ahead and test those waters. I don't believe in pissing away money though.

Philip, what characteristics didn't the PO of your injectors like about them?
 

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He realy didn't go into much detail. He just said he didn't like them. So I didn't push the issue.

Anything bigger than stock injectors is better except POD's. :lol3:
 

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Discussion Starter #16
Now im really aprehensive:CRY: I definately do not want to sacrifice the reliability. What would be a safe adjustment 1 or 2 turns? Im thinking about not messing with it at all and just saving up for some big injectors
 

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Each pump is different. There is no way to tell if your pump has allready started going away. A stock pump when it starts going bad normaly doesn't give many signs. It will just start gradually losing preformance that most owners might not notice till the pump is almost dead. Other times you might get some noise in the pump.

The one pump I have seen fail wasn't hard to tell it was going. It was making a clicking noise and was way down on performance. The exhaust didn't smell right. The cruise couldn't keep up on hills. The fuel milage was good on it seeing as how it wasn't giving much to the engine.:rof
 

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Now im really aprehensive:CRY: I definately do not want to sacrifice the reliability. What would be a safe adjustment 1 or 2 turns? Im thinking about not messing with it at all and just saving up for some big injectors
I doubt that you're gonna have any troubles with the IP due to the fuel screw. Max it out, then go get the injectors of your choice and tune it down if needed. The pump will only fail if it's already weak. I think the other big deal on a hot rod VE is fuel supply. Cool fuel and no 0psi at WOT.
 

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What reasoning would KTA have to lie about his results? Besides, Swank and him both made 600+ with 6X.016 injectors. Volume makes HP but without atomization you have nothing. Go ahead and test those waters. I don't believe in pissing away money though.
Who knows how the bigger injectors would react with more swirl in the head porting, with lower or higher compression, with a higher lift cam plate, or with methanol assistance.

It's a good trend that you don't want to go any bigger on injectors, but I wouldn't call it conclusive.

Not to mention that injectors that big from a different shop might be totally different critters.
 

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so how do we get those injectors? i dont have an injector shop here so i need to order new off the internet.
 
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