SouthernIDI
Registered User
I'm running a GSL 395, its not rated for diesel either, but it has held up for 6 months now, and its super quiet.
Holley Red are garbage, what else quickly?
- Thread starter DOE-SST
- Start date
ISPKI
Welding/metallurgical engineer/Metalsmith
Facet pumps dont have the flow volume to keep up with the demand of the IP. They are generally fine at lower RPM but their pressure drops as engine RPM increases. There was a study done on here some time ago, might have been by Agnem, I dont recall exactly but the pressure of the Duralift pump would hit 0 right around 3,000rpm, meaning the IP had overcome the facet's ability to move fuel and the IP was effectively sucking fuel thru the pump.
How that effects real performance; the pressure of the lift pump influences your IP timing. I believe, as the lift pump PSI increase, it advances the IP timing, and as the lift pump PSI decreases, the IP timing retards. The issue with the Facet losing PSI all the way down to 0 is that the IP will lose some degrees of advance, resulting in a loss of power in the higher RPM range.
The real question is how much and does it really matter? I seem to recall as much as 1 degree of timing loss per PSI loss. With a 6ish PSI output, that means you could retard timing by 6 degrees. I dont think its really well correlated or documented but that number sticks in my memory. Whether or not you really notice this is anyone's guess. Some might, some might not and if youre not really pushing your truck hard, it probably doesnt matter.
However, this is why the mechanical pump is so good. It produces a static pressure, but a dynamic flow, because it is mechanically driven, as your RPM increases (and your fuel demand) the mechanical pump also accelerates, putting out higher volume to match your demand at all RPM ranges.
How that effects real performance; the pressure of the lift pump influences your IP timing. I believe, as the lift pump PSI increase, it advances the IP timing, and as the lift pump PSI decreases, the IP timing retards. The issue with the Facet losing PSI all the way down to 0 is that the IP will lose some degrees of advance, resulting in a loss of power in the higher RPM range.
The real question is how much and does it really matter? I seem to recall as much as 1 degree of timing loss per PSI loss. With a 6ish PSI output, that means you could retard timing by 6 degrees. I dont think its really well correlated or documented but that number sticks in my memory. Whether or not you really notice this is anyone's guess. Some might, some might not and if youre not really pushing your truck hard, it probably doesnt matter.
However, this is why the mechanical pump is so good. It produces a static pressure, but a dynamic flow, because it is mechanically driven, as your RPM increases (and your fuel demand) the mechanical pump also accelerates, putting out higher volume to match your demand at all RPM ranges.
SouthernIDI
Registered User
I ended up going to E fuel because my eccentric is TOAST, and im really not dealing with that right now.
tbowker
Full Access Member
I appreciate that explanation. Apparently there's more going on than I expected. Okay, so then theoretically, I should be able to put a fuel pressure gauge in the cab and watch the pressure go nuts. Now I'm thinking that'll be my next project. I live in Florida, so there's no mountains to climb unless I'm going over the skyway bridge. I haven't noticed any substantial loss of power when pulling a trailer, but the most weight I've pulled is about 8k pounds.
I've had enough issues with mechanical pumps where I won't try that again. Who makes the best electric fuel pump for these trucks?
I've had enough issues with mechanical pumps where I won't try that again. Who makes the best electric fuel pump for these trucks?
u2slow
bilge rat
That sucks.
Sometimes you gotta roll with what you can get quick n easy. Pack a spare if its failure-prone. Start making moves to get a mechanical back on there.
ROCK HARVEY
Full Access Member
Regarding fuel pressure, the DB2 service manual says the following:
Basically as long as my fuel filter light isn’t coming on, I figure my lift pump is giving the DB2 all it needs. 1PSI is perfectly fine. That being said, I still want to add a fuel pressure gauge inside the cab just so I know how plugged my fuel filter is getting. Holley makes an electronic fuel pressure sender/gauge with a 0-15psi range, but it’s more than I want to spend right now.
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Basically as long as my fuel filter light isn’t coming on, I figure my lift pump is giving the DB2 all it needs. 1PSI is perfectly fine. That being said, I still want to add a fuel pressure gauge inside the cab just so I know how plugged my fuel filter is getting. Holley makes an electronic fuel pressure sender/gauge with a 0-15psi range, but it’s more than I want to spend right now.
SouthernIDI
Registered User
You're goin to get a different answer from everyone, Holley red, and 40222 facet, are going to be the
most typical answers for E fuel setups. Just like any following you'll have the people that call the Holley
red trash and you'll have the people that call the 40222 trash. Only reason i went with a Walbro high
pressure pump is because i stole my design from Justin Anderson, I wasn't paying $800 for what took
me just shy of $300 to build. Do some research on the matter and pick the pump that you think is going
to do best. All i will say is that i have went the 40222 route with no luck. Truck idled fine, but anything
over 2,000 rpm the fuel pressure would drop below 1psi and begin to fuel starve.
tbowker
Full Access Member
Okay, so you went with a high pressure pump. I presume that isn't causing any fuel leaks since the walbro pump I looked at was somewhere around 45psi. That just seemed like it would find ways to leak since the stock fuel system is expected to run at around 9psi IIRC. Did you modify your fuel system where it connects to the injectors?
Judging from what ISPKI had to say, it seems like higher pressure would change timing. Did you notice anything like that?
ROCK HARVEY
Full Access Member
One thing I should make clear is that my truck is NA, and the fuel screw isn’t turned up. That may be the scenario in which the 40222 is viable. I was 100% planning on a Holley red when the 40222 dies, but now i’m second-guessing that option as well. Airdog makes a 100gph pump in their raptor line that is set for 8psi. That may be the ultimate solution for me but it’s $330 on Amazon.
SouthernIDI
Registered User
Yes, I changed my entire fuel system. This is what I've done-
From my sump it goes to a 2 micron Fuel water separator, then the walbro high pressure pump, then a 1 micron fuel filter, then it goes to a Holley bypass regulator set to 6psi mounted on my fire wall, from there it goes directly to my IP. So my IP only sees 6psi of pressure.
IDIBRONCO
IDIBRONCO
Yes. They both did. From 1988 (I think) whenever it was that they dropped the square bodies) on, they ran an electric lift pump.
All our smog natzi fuel has that garbage in it.
So if the vatozone mechanical pumps are a dicey crap shoot.
Holly FTW
Moral of story...
Go out and vote, call your reps and b i t c h about corporate chimerica shoving garbage down your throat.
Go out and vote, call your reps and b i t c h about corporate chimerica shoving garbage down your throat.
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tbowker
Full Access Member
Okay, I like the sound of that. How long have you been running that modification and can you include pictures?
tbowker
Full Access Member
I'm running a 7.3 Jasper remand engine with a banks turbo. I haven't tweaked the fuel screw at all. The mechanical lift pump crapped the bed at 2300 miles and I've had this 40222 installed for around 7k plus miles. I've had no problems but if there's a better solution I'm all for it.
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