Exactly like it says why couldnt or has someone already tried this. I know the old mechanical lift pumps used to push alot higher PSI and fluctulated alot but couldnt that be regulated?

Shoot why couldnt someone put in a PDR cam with the lobe for thier 1998-2002 Gen2 24v and solve the lift pump blues?

wouldnt this be the best of both worlds? mechanical lift with variable timing injection and a PDR cam all at the same time?

Who has played with this idea and what are the barriers to accomplishing it, would an earlier Gen 1 lift pump push less pressure than the Gen 2 LP which pushes 25psi at idle? how about reliability? Mine seemed fairly reliable.


Just a thought and possibly worth discussing.

 

This should be an interesting thread to watch.

 

Seems to me that a cam swap is way too much work, just to have a mechanical FP, especially considering that the RASP(mechanical) system is available. It may not have much history yet, but it has lots of protential.

 

ddestruel,

Yes sir a mechanical lift pump off of the cam is a great solution. When I first contemplated doing it the only cam for the 24 valve with the fuel pump lobe on it was Diesel Dynamic's. (And at that time they were $1800.) I know of a couple people on this site that are running a cam operated fuel pump on their second Gen, Jim Fuller and Mike Ramos. Also I know that DDP does this mod up here in WA.
As you can see from my signature I run a mechanical pump too. (The RASP.) It is driven off of the crank and is cheaper date than converting to the 12 valve fuel pump. Not to mention it utilizes the original electric pump system for a back up. Either way a mechanical fuel pump is the only way to go!

Opie

 

OPIE, how many miles on your RASP? I am thinking that when my Holley bites the dust, I will go w/the RASP.

 

Or actually, just start saving the money for the RASP, and install it before the Holley dies.

 

Yes and no. I can change out the cam fairly easily, so that is no a concern. and the talk of bandaids with potential has gone on for years. Holley pumps, PE, .........


The idea of the mechanical lift pump is that it is available Anywhere appeals to me over the Rasp or FASS simply because it is something that i can get at any Cummins dealer or parts house. plus it is 1/2 of the P pump conversion if i ever do a p conversion. My hold up is i would probably have to change wiring harnesses since mine is an 02 6spd with the eletronic Cruise control


But debating that isnt the issue, what is are the PSI issues that mechanical pumps present, what pressure does the Gen lift pump put out, is it reliable?

Really Jim is running a VP44 with a block mounted mechanical lift pump? I didnt realize that, i thought he had a 12v.

Is there a regulator out there that could stand up to the mechanical LP and its constantly increasing pressures as R's run up and what is it.................... how could one go about setting up a configuration like this?

 

This sounds interesting to me.

What is the benefit to the cam swap?

If it works PDR (or who ever) could sell a complete package,
Cam, lifters, pump, regulator and high flow fittings.

"Not to mention it utilizes the original electric pump system for a back up" Couldn't that be incorporated into the cam swap / mechanical pump swap also?

"The idea of the mechanical lift pump is that it is available Anywhere appeals to me over the Rasp or FASS simply because it is something that i can get at any Cummins dealer or parts house. " I agree

 

I get this question a lot. Truth is when I installed it in Jan and found out about the 5 year warrantee I didn't worry about writing down the exact milage. ( At the time I was amped on testing it out.)
My truck is my everday driver, the longest trip this year was to Muncie IN. Outside of playing with the fuel pressures a few times, the RASP and watching the fuel pressure guage for that matter is boring...
It just works, whether I am running the Mach 2.5's with the box off or the 6's with NOS and the Comp on 5X5. The fuel supply problem's are gone.

 

I know Chace at www.westtexasturbodiesel.com has done a few of these also. I f he'll answer his phone(always busy in the shop), he can give some great info also. Hope this helps. cumminsboy

 

ddestruel

I broke up your quotes to give my feedback to your statements.


"Yes and no. I can change out the cam fairly easily, so that is no a concern. and the talk of bandaids with potential has gone on for years. Holley pumps, PE, ........."

The cam in my truck is still the stock one though I have helped do a couple... I wouldn't exactly say they are that easy to do. (Then again I am an old guy.) But I can see where you are coming from.

"The idea of the mechanical lift pump is that it is available Anywhere appeals to me over the Rasp or FASS simply because it is something that i can get at any Cummins dealer or parts house. plus it is 1/2 of the P pump conversion if i ever do a p conversion. My hold up is i would probably have to change wiring harnesses since mine is an 02 6spd with the eletronic Cruise control"

Thats a good point, my reply is I don't plan on needing to change a pump. If the pump where to take a dump I would still be driving around as the back up would automatically be on while I waited for the replacement to come in. What if your Cummins pump died and there wasn't a Cummins dealership around? To anyone who travels the RASP makes sense. Not to mention if it had to be done the RASP pump is easier to change and faster to prime.
Why would you want to P-Pump a 6 speed?

"But debating that isnt the issue, what is are the PSI issues that mechanical pumps present, what pressure does the Gen lift pump put out, is it reliable? "

On NWBombers Jim Fuller said his 2002 ETC barried 30 psi at idle after going mechanical.

"Is there a regulator out there that could stand up to the mechanical LP and its constantly increasing pressures as R's run up and what is it.................... how could one go about setting up a configuration like this? "

A regulator should be an easy enough find.

 

A few of whats? RASPs, mech. pump for a 24v, FASS, ???? ?

 

Mechanical pump swaps on a 24 valve, sorry for the screw up . cumminsboy

 

HMMMMMMM I'll have to digest that.

Thanx Opie

Dusty