EZ w/ stock injectors, is this hard on the VP44?

[AKDrifter]

So I'm running an EZ with stock injectors, this just about gives me all the power I need. Am I making the VP44 work harder than it should? I know the pump is able to flow the fuel, but would'nt running 275's make the pump work less hard with the same power demand?



Is this what is meant by "smooths it out"? It feels like when I need the power it wants a bigger sip of fuel, making me push harder, which works the pump harder. Should I be putting in 275's for the sake of the VP?



I know I'm putting this question in front of the wrong crowd, but

is'nt this a good reason (not excuse) to go bigger? Paul

 

[Bigsaint]

Paul, IMHO, the EZ box isn't adding enough fuel to worry about a injector upgrade if you are happy with the power that you now have. Also, I don't believe the the EZ box is taxing your injection pump, at least not to the same extend the pump wire tap boxes do. That being said, many here run their tap wire fuel boxes constant and still get a good long live outta their VP44.



I'd just keep an eye on your fuel pressure as a dead lift pump is much more likely to ruin the VP44.



Scott W.

 

[AKDrifter]

Scott, yes I'm happy with the power for now. As is, this thing will tow anything I need or ought to be towing. The EZ box realy let it go and has made all the difference pulling hills and moving along. Fuel preasure is good, never gets below9 psi. wot. Can't imagin towing with a BOMBed out rig, feels like can pull a house allready. Paul

 

[Big White Beast]

Paul.....

I think your VP will be fine. The only thing to think about when upgrading to larger ijectors will be your clutch. 275's might push it past the limit.



As far as everyday driving you won't notice much with 275's, maybe a little better mileage. When you need some extra power though it's there, hence the extra load on the clutch.



Garrett

 

[Stiffler]

Originally posted by AKDrifter

Scott, yes I'm happy with the power for now. As is, this thing will tow anything I need or ought to be towing. The EZ box realy let it go and has made all the difference pulling hills and moving along. Fuel preasure is good, never gets below9 psi. wot. Can't imagin towing with a BOMBed out rig, feels like can pull a house allready. Paul

I see a lot of posts where bombing will tax the clutch. In general do these posts mean "while towing" your clutch will give up or running with no load your clutch could still slip?

 

[CUMAPART]

Stiffler

It all depends on how much bombing you do. I have had my EZ on for about 25000 now and clutch has been fine. Some people have reported bad luck with their clutch as soon as they install a box. I am getting hungry for more!!!!!! Maybe time to call SBC :-laf :-laf

 

[jtisdale]

Just a heads up

I too ran an EZ for a while. Then I added 275's at a good friends house (Johnrv4) and on the way home, the clutch slipped twice. This was empty. I am still running this combo (6000 miles) since the addition of the injectors. It only slips in 5th and 6th when I get on it with the rpm too low (under 2000). Some guys have reported no problems at all with a DEE and this set-up. Its a gamble, and I lost. I was planning a clutch upgrade anyways, just not this soon, so be ready. Its not like your clutch is going to completly fail, it just wont hold the torque at the lower rpms.



As for the vp, sooner or later it will give up... like it or not. If you drive it, it will fail. Just the nature of the beast. Keep the fuel pressure up, run clean fuel, and change the filter often.

Remember if you BOMB, you are your own warranty station. If you dont, its DC's baby till the clock hits 100,000 miles, then its yours. I am not trying to lecture you, I just want you to have a perspective on the big picture.

Spend your hard earned $$ the way you want, and have fun doing it. These rigs are a lot of fun!

 

[RustyJC]

By virtue of the fact that the EZ communicates via the CANbus, it will not overfuel beyond the limiting parameters already programmed into the ECM. It just tells the CANbus to give more fuel than would otherwise be called for, but the limits in the ECM still set maximum fueling, and these are not exceeded.



Not the case with the boxes that tap the pump wire downstream of the components that set these limits.



Rusty

 

[GiesJ]

AKDrifter-

I'm by no means an expert - but I'm on my 4th VP44. There's another thread floating around about that story.



I think the key is to monitor your FP. If (excuse me, WHEN) your lift pump kicks it you want to fix that ASAP so the VP doesn't have to work harder and possibly have lube issues. I don't know if you have a FP gage as part of your gages but I highly recommend it. As for the EZ, I think this is a good article about the VP44:

http://www.bluechipdiesel.com/Bosch-VP44.htm

 

[AKDrifter]

I do keep a tight eye on the FP, and was very happy to see 14psi. at idol, 11 cruising, and no less than 9 at wot, not that guy needs to be driving wot all the time, just good to know.



Think it's time to go with a pusher pump for my next mod, located where I'm at and the dealerships I have to deal with, anything I can do to keep me out of there is a good thing! The '03 has a dirrerent IP correct, not controlling the the pulsations but more keeping constant preasure to the common rail system? Seems like quite the upgrade from our fuel delivery system. Paul

 

[CRSmith]

The way I understood it: An EZ shows the computer 19. 9psi (approximately) of boost at all times. 20psi is the wastegate limit and code setting limit. The computer has fuel curves in which one of the variables is boost. If the computer sees max boost at all times it ceases to become a limiting factor, thereby giving you full fuel on tap at any boost level. So, like Rusty said, the stock limits of the VP44 aren't ever exceeded. But it is at its stock limit more often. Then the other factor is timing which is a whole separate issue.