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When you chip you MUST put on a better fuel pump

Pillow

Pillow

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Just a statement from my experience.

I run the HP4 chip in the 96 and it never seemed to have enough get up and go. Most people claimed that a new/newer factory pump could feed the IP in normal conditions... I disagree.

I spoke with Todd at Heath and he said to try their HD lift pump, and I did. WOW what a difference! The truck will finally pull hard through all the gears and even has a little diesel left over to puff a little soot. LOL

Right now the new lift pump has been installed for a few weeks and I thought I could give a good review at this point. Yesterday I took a mountain trip and could easily climb sustained 8% grades at 13-15PSI between 55-70MPH and held the temps between 900-1000F. And I still had pedal left to go.

I am not going to talk down the Walbro option at all, but at this time I see no advantage for the conversion under normal conditions with the Heath product available.

Still to do:
- ATT turbo conversion
- Feed the beast mod

Thanks!
 
IIRC, that would be the '92-'93 and '98^ lift pump, as opposed to the '94-'97 lift pump - more output, which is good, but is not magic, as it still wears out same as the '94-'97's - at any rate, even tho replacing any old hi-mileage lp with a new one is gonna seem like nite'n'day to the driver, opt for the better pump - all the GM solenoid-pumps are variable-flow, shutting down at rated pressure - this prevents aerating the fuel, which the constant volume motor'n'vane pumps do - the old engine-mounted mechanical diaphragm pumps were variable volume, low-flow at idle, increasing as engine rpm and power increased
 
Well one advantgage to the Walbro is that it's rebuildable so cost in the long run is less. With the stock pump you just have no choice but to replace when dead. That was my main reason for going that route. Also the Walbro is quieter than the stock one by a lot.
 
Primary thing to remember is the DS4 will getcha home if the dead lift pump is flow-thru when fail - meaning, the DS4 can still pull fuel thru the dead pump - not enuff to race, but enuff to keep you moving to a safer spot, even getcha home - most of the motor-driven pumps are not ftwf, which will stop you dead wherever the motor stops churning the vanes
 
Is the Kennedy pump the same Walbro?
I read a post at the Place a while back & someone said the Kennedy pump didn't hold up in extreme cold weather. Anybody have any cold weather experiences with Walbro, Kennedy, or other non-stock pumps?
The Heath GL-4 is something I'll eventually spring for, and I'd like get a more reliable LP too, but it's gotta work in the cold.
 
Haven't had any trouble out of my Walbro yet and it got pretty cold here this winter but not Alaska cold. You could call up Walbro and get the specs. I lost the web address when I reformated my drive to clean it up but I think if you search you could find it pretty easy. I don't know anything about the kennedy pump.
 
My Walbro ran this winter with no problem. I thought it was a great replacement for the stock pump, gave me a few more psi and just looks and feels like a more substantial pump.
 
Anybody have opinions on the Walbro vs Kennedy/Duramax? Kennedy's has the 6.5 fittings installed, so it should be pretty much bolt in.
 
If the ground has dried out some tomorrow night I should be installing mine. Didn't feel like laying in a pool of water running an electric drill tonight.
 
The JK lift pump is an electric motor-driven vane-type pump, with the added advantage for Diesel fuel that it is magnetically coupled, no direct connection between pump and motor - this means that it is a variable volume, constant pressure type pump - the magnetic coupling allows the motor to run at full speed while pump speed varies according to volume demand - thus the motor freely runs while the pump spins just enuff to maintain pressure at idle - as engine demand increases, pump vanes spin faster to keep up with demand - this emulates the engine-driven pumps and the GM\AC\Delphi solenoid pumps, but with way increased available volume over the solenoid types - 'course, the CP3 on the DMax has it's very own very powerful built-in mechanical lift pump, making the JK lp a supplemental pump, but, if you can afford it, the JK pump would be a very good installation for the 6.5: constant pressure, variable volume, flowthru when fail - also, because the magnetic coupling decouples at a non-linear rate (variable loading), the electric motor will last longer than the motors with shaft-driven pumps - those motors usually crap out long B4 the pump wears out
 
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I totally forgot to mention that the Heath LP is very quiet. I had to feel it to ensure it was running the first time! Granted if you listen very hard when waiting for the WTS light to go out you can hear it... The old Carter pump was loud as hell.

If the Heath LP and 93(high output) LP are the same, I do not know.
 
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