Comp and VP failure?

[Scheibins]

I installed my DDUFM tonight and have DD2s.



I wanted to get some reassurance you all. I've driven it about 15 miles. About ten of those miles, I was on 3-3 and for two 0-70s I had it on 5-5. And I made it home , I was worried about the VP. I've noticed most of the failures have happened shortly after the pump wire was connected (which, btw, I did on the install). So is my VP concidered relieable now?



I'm going to have to keep the level down, until I figure out what sort of fuel upgrades I want to do. With just the DD2s at WOT I would drop to 8psi, now at full power I drop to 2psi or under.

 

[csevers]

For your sake I hope it has a long life

I have had my pump wire taped since about 15k and on an early make of the VP-44 even had a dead lift pump for some time and still my little fuel pump continues to run, it is most likely luck that it has survived this long and I hope to be the one with the 500k mile VP-44, but I am not holding my breath. If it has made it past the first thrashing it will probably run for some time. BUT there is always the chance of it going totta's up at any time.



Good Luck

Craig

P. S. I drive on injectors alone most of the time also and use the box only for good not evil... lol

 

[Sticks]

Set up a bank account with $800 in it and flag it as NO TOUCHY. There is your replacement VP44 fund (providing you DIY the install). Most of the deaths that I have read happen within the first 20 minutes, after that it's anyones guess. Could be tomorrow, could be 100,000 miles from now. Just keep the fuel pressure up, and let the truck warm up good before you start upping the fuel with the box (READ - playing, high settings on the comp).



I'm overly cautious and my new injectors are going to cost me $1400 (clutch fund) and a comp will be another $1400. It's gonna' be a while before I can play.

 

[fox]

I put the comp on mine at 4,000 miles and hooked the wire up.

Now it has 40,000 and is fine.

Let me add that you should run a fuel lube as a safety net.

 

[24V-DSL]

You are wise to know that low fuel pressure is risky. I've lost one VP44 with a Ray T. bigger banjo system and 2-4psi WOT pressures. Upgraded to the Wildcat Diesel maximum fuel line kit, and now can't get it under 10psi. There are several options for improving fuel delivery/pressure. Do a search, if needed.



IMO, the VP's are inherently weak, stock or bombed.

 

[Bigsaint]

An old wise man once told me... " make the bulk of your HP with injectors, save the boxes for play". While I have no conclusive proof that is good advice, that's what I do.





If you are running a box and taking a stab at WOT runs, becareful at the end of the run and keep the throttle open slightly, to keep the fuel flowing through the VP44 and allow it to cool and stay lubricated.



Scott W.

 

[Mundgyver]

I run a comp and a set of 275's. I have 110,000 now on my VP with no problems. My stock lift pump is still good but was replaced at 103,000 with a FASS because I did not want to tempt the the LP and VP gods.



I believe the secret, or at least part of the secret to keeping the VP healthy, is to run Diesel additive on a regular basis. In my case that equals a 32 oz bottle of Power Service every other tank. I'v been doing this since the truck was new.

 

[CFAR]

It seems that most of the vp's to die after hooking up the wire, were the earlier versions 98. 5-99. I just hooked mine up at a dyno day, figured I could find some people to help if it died, so far it hasn't. I can only pull mine down to 7psi wot. So 2psi sounds like you need a new LP. $148 from cummins, plus you can throw the old one in the tool box as a spare.



As far as Inj/box goes. You can't turn off the Inj. But I do the same thing my box is on 1x1 99% of the time. Untill it gets too bright outside and I want a little cloud cover.

 

[jrandol]

Ditto,the prior philosophy on running on injectors. Who knows, my pump could go south tommorrow and make me wrong but I run 99% of the time with just injectors on my truck. The box is for waking me up or embarrassing a ricer, Camaro/Mustang, or a goofy PSD/Dmax. I have this crazy theory that playing with the pump timing also hurts the pump, nothing to really back it up but I still believe it.