performance lift pump low pressure piston or raptor electric?

[TFaucette]

truck is low on power and I suspect it's low lift pump pressure and once I check and if it is low how much hp will the low pressure mechanical piston pump supply and have access to a free used pump on a 97 but heard you need a low pressure that the VE can't handle it , also if better for a 400+ hp ve would a raptor electric be better and if so if I am going to stick with a VE and mabey a 4mm camplate and possibly 14mm head and keep my 5x. 012's will a 100gph work or do I need the 150? also open to other suggestions of adequate supply for a tight budget.

 

[RSchwarzli]

Well, few thoughts:

1 - If you change to a second gen lift pump, you will also need some of the 2nd gen fuel lines that feed the filter housing and all.

2 - What is the current lift pump pressure? I find mine will range from 5-6. 5 depending on outside temp, fuel grade, boost numbers, and driving conditions. I occasionally see 4. 5 at WOT. Last summer I was nearly bottoming out my gauge so it was deemed my old lift pump was dying. A new one solved the issue.

3 - The easiest way is still to do an electric pump if you really feel that the pressure is low. Replacing the existing one if it is worn out may also assist with the issue.

4 - If you are really concerned with too much pressure, can always regulate the to VE pressure.

 

[ENafziger]

The Raptor pumps that I've seen (including the one I have) all have a built in regulator that is adjustable. I'd install the Raptor and regulate to about 10 psi. Unless you're going over 500 hp, I think the 100 is fine. The biggest thing you can do to help performance is use a larger diameter line on the suction side. If you're really interested, I can look up equations, but for that flowrate, you should use at least a 1/2" line on the inlet side of the pump. For the outlet side, 3/8" is fine.

--Eric

 

[TFaucette]

installing low presure piston pump but can't get it to clear the top of pump where metal fuel line goes in (fuel comes out) is hitting the plastic box around the blow by tube, can i cut on that box or is that something i can chage or anyone has ecountered?

 

[Ncostello]

I've not upgraded to a Cummins low pressure piston pump yet... but it's been on my list. But in my research I do remember reading about some minor trimming to something there on the driver side of the block. Whatever it was it was simple and could be done with a dremel or whatever. Kinda required a notch out cut and wasn't supposed to hurt anything. Not that this helps you alot. There is an old thread on here somewhere about this.