Stock lines and a double pumper?
- Thread starter WFO
- Start date
Welcome!
By registering with us, you'll be able to discuss, share and private message with other members of our community.
Whoa.
So the stock fuel lines in conjunction with a double pumper are not exactly a cork.
That apparently leaves the stock fuel rail and injectors.
It's already been established that 83#s are good for 500 hp.That's with a stock fuel rail with a -10 fitting welded on.
Fortunately for me 10.0 and 135mph are as fast as this car's ever gonna go.
So does anyone have any idea what flow level the stock rail inlet really becomes an issue?
So the stock fuel lines in conjunction with a double pumper are not exactly a cork.
That apparently leaves the stock fuel rail and injectors.
It's already been established that 83#s are good for 500 hp.That's with a stock fuel rail with a -10 fitting welded on.
Fortunately for me 10.0 and 135mph are as fast as this car's ever gonna go.
So does anyone have any idea what flow level the stock rail inlet really becomes an issue?
GNVYUS 1
Well-Known Member
- Joined
- Dec 15, 2002
- Messages
- 4,364
Considering that you will need around 30% more E85 at WOT, running the stock lines is a huge waste of injector pulse width and not worth keeping, especially for E85.
If you ditch the narrowing on the stock rail you have done your fuel volume at WOT a huge favor.
Personally, if you plan on running 135mph on E85, go -10 feed and bigger aftermarket rails. Why chance a motor over $500 in fuel system upgrades.
Hell, I did the above so I can run my 340 with alky to the max on gas.
If you ditch the narrowing on the stock rail you have done your fuel volume at WOT a huge favor.
Personally, if you plan on running 135mph on E85, go -10 feed and bigger aftermarket rails. Why chance a motor over $500 in fuel system upgrades.
Hell, I did the above so I can run my 340 with alky to the max on gas.
So how do you connect -10 feed line to a stock tank/pump?
I was under the impression that you would have to sump the stock tank or go with a cell to run big lines...
Those upgrades can certainly help. FWIW I've seen nearing 600 lb/hr of flow out of mine when it still had stock lines. I used that as a threshold that it was ~ time to change to a -8 feed from pump(s) to tank, and an upgraded filter 
But I had the FAST at that time too with wb closed loop control, so was not as worried about pushing that volume threshold. In this case we'd know something was falling short (before blown up engine hardware told it), could look for signs that it was not keeping up as the performance steadily increased. FWIW I never saw those signs of it not keeping up, even throuh the stock lines with 30+ psi boost out of a 76 q-trim, on a 4.5L GN1-R's mill. Then after 1st upgrading to a -8 feed and bigger filter, add a 175 shot of nitrous on top of it all, also fueled through the port injectors (160's).
In short, it flowed alot of fuel for a real street car And the fuel filter got/needed regular attention.
Our list member John Estill calculated the losses through varying diameters of feed line (he does refinery related design work for a living). It helps to see those results too.
My advice would lean along with the others here; in reality you could probably get away with no line/rail upgrades for your stated goal, might get close to the edge getting there. But also probably an even better idea to be more conservative and upgrade things a bit if you do intend to go 135'ish on E85.
TurboTR
But I had the FAST at that time too with wb closed loop control, so was not as worried about pushing that volume threshold. In this case we'd know something was falling short (before blown up engine hardware told it), could look for signs that it was not keeping up as the performance steadily increased. FWIW I never saw those signs of it not keeping up, even throuh the stock lines with 30+ psi boost out of a 76 q-trim, on a 4.5L GN1-R's mill. Then after 1st upgrading to a -8 feed and bigger filter, add a 175 shot of nitrous on top of it all, also fueled through the port injectors (160's).
In short, it flowed alot of fuel for a real street car
And the fuel filter got/needed regular attention.Our list member John Estill calculated the losses through varying diameters of feed line (he does refinery related design work for a living). It helps to see those results too.
My advice would lean along with the others here; in reality you could probably get away with no line/rail upgrades for your stated goal, might get close to the edge getting there. But also probably an even better idea to be more conservative and upgrade things a bit if you do intend to go 135'ish on E85.
TurboTR
GNVYUS 1
Well-Known Member
- Joined
- Dec 15, 2002
- Messages
- 4,364
I had Turbofabricator make me -8 and -6 fittings on my stock hanger.
The -10 would be what I would do for E85 and it would have to be out a fitting in the sump, though I bet Turbofabricator could make you a stainless pump hanger with bigger tubes and a -10 on the end. But then you have it sitting in a steel gas tank.
And Walbro is supposedly testing E85 pumps, so not sure how the standard double pumper with 340's will last on E85 if they report that the pumps are dying much faster ( lubricity is big here ).
The -10 would be what I would do for E85 and it would have to be out a fitting in the sump, though I bet Turbofabricator could make you a stainless pump hanger with bigger tubes and a -10 on the end. But then you have it sitting in a steel gas tank.
And Walbro is supposedly testing E85 pumps, so not sure how the standard double pumper with 340's will last on E85 if they report that the pumps are dying much faster ( lubricity is big here ).
