ok, so if you have been on these boards for the last couple years you notice that people always complain about 1/4 tank cut. I have been very upset with this and I have found out exactly what causes this issue, no more, "I think" or "cut the cup" it is all about put the right pump, in the right way. Ok so on to business... (I am all dirty and have the tank out right now, so I am likely making spelling mistakes and such, I appolagize)

The Canister is supposed to be 100% full all the time, even over flowing, but with the walbro 255 it stays at the exact level of the gas in the tank, even if you cut the cup you are still at the exact level in the tank... so if you are screwing arounf under 1/4 tank you get fuel starvation. Well, lets take a look at the stock GM pump, how do they get the canister full all the time??? look at this:






That little hose runs down to the bottom and has about a 0.5mm nozzle that sprays about 15 feet (think a mechanical pencil 0.5mm.. or smaller even), it injects at a really high speed and pulls fuel from the rest of the fuel tank up into the canister keeping the canister over flowing at all times.. and becuase it flows so little it doesn't have any effect on fuel supply to the engine.

I test ran the stock pump and it instantly filled the canister 100% and over flowed it, then I put the walbro in (it doesn't have this output) and the tank was dry within seconds.. and I was asking myself, how does the car run at all??? Take a look at the high velocity (remember increasing velocity, decreases pressure... therefore sucking fuel in) 0.5mm spray patternbad phone vid, but it sprays hard into the card board and almost hit the ceiling, the sound is encoded stupid too)

http://s36.photobucket.com/albums/e45/ge_forcez22/?action=view¤t=SSPX0132.flv

For now I don't have another pump with the same GM second output to fill the canister, so I will leave it like this:


so approximatley double the fuel (hopefully) can fill the canister (but only to the level of the fuel tank) until I find a pump that has that secondary output designed for GM canisters.

The next time you start your car just think, that 2 seconds the fuel pump turns on is not just pressurizing the whole fuel system, it is infact filling up the canister ensuring proper supply during operation


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

thats the same way I did mine last weekend, and you took the little plunger deal out right?
What was the # of the pump you used?

I was pretty low on gas (probably about 1/8th of a tank) and it still pumped fine..


------------------------------------------------------------

PS.. that is a 2000 module.. not all moduals look like that.

All you have to do is T off the main feed line from the pump and run another 1/4 line down to the bottom of the canister. The 3800 guys have been doing this for a few years now and it works perfectly. Hell I would of posted this up long ago but I just figured you guys knew.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

Or, you could use the GTP fuel pump and install kit hehe.. But you already knew that Hopefully you realy got the fix for the cut.











~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ

WHITECAVY wrote:Or, you could use the GTP fuel pump and install kit hehe.. But you already knew that Hopefully you realy got the fix for the cut.

I had to laugh when I got my ZZP 3800 specific walbro install kit. Thats all it was guys, a t fitting, some hose and two hose clamps. I will go take some pics in a min of what I am talking about.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

I have asked and asked and asked, and never yet got the answer. the walbro is a #2555. I tested it in about 1 liter of gas, and it filled the canister up instantly and seems to work fine, I had no outlet on my walbro so I drilled into the top piece and threaded in a bolt which I drilled out and cut the top off. \

Before I started I drained the tank as far as the walbro could get fuel, I am hoping it will start up below 1/4 tank now.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

alrighty, it rus great below a 1/4 tank, I ran it to 1/16th tank, then filled up.

This is the mods I did, cause I wanted it done right. I went and picked up a bolt and drill bit.


then very carefully, drilled through the bolt and cut the end off


then I picked up a little tiny hose clamp


this is what the stock pump looks like


so I drilled the bejesus outta it


looks like this finished product


I threaded in the cool little bolt I made


finished product




HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Get that thing in the car and let us know if it works!


15.3 @ 89.97mph - '01 SFGT
'98 Acura 1.6EL Sport 5M Y7/Y8 mini me

Ian, it works 100%, right till empty on the gauge, and pulls perfect up top, can't say I would do it any other way, DRILLING FTW


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

cavmania wrote:thats the same way I did mine last weekend, and you took the little plunger deal out right?
What was the # of the pump you used?

I was pretty low on gas (probably about 1/8th of a tank) and it still pumped fine..

I left the plunger in, that way when you shut your car off, the canister stays full.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

You've got to be kidding... The Walbro pump doesn't have the outlet for the venturi style jet pump? But... the enitre reason for the complicated, expensive, spring loaded sending unit assembly is the venturi system which allows fuel to be drawn all the way down to the bottom of the tank. And that sender design is now used on most GM vehicles. Hard to believe this pump is being sold for so many applications.

I guess it's a good thing I haven't ordered a Walbro pump for my 93 or I'd be more than a little disappointed.

-->Slow

I wonder if there is a better Walbro pump for our cars.



FU Tuning

Good work ge force I'm glad to hear you fixed ur problem with the fuel cut. Now I know how to install it when I
get my hi flow intank pump.

nice dude, if only i still worked at walbro, i would snatch up a boat load of the outlet covers like the one i used on my pump. its it exaclty like ours but has a little brass barb acting just like the bolt you threaded into it.

nice work.

I need to get around to doing this some day....... I thought at one point someone posted a link up for a Walbro with that small nozzle.

Raven..... its funny thats how ZZPer. fixes the issue on the GTP..... As long as it works I guess.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

this is great news! so the correct walbro 255lph pump we need is #2555? and we just make the modifications you did above, and it'll work with no 1/4 tank cut?





http://jbok.org

^^yup, but they really should make a better pump for our cars. Keep in mind that @ 71psi fuel pressure the 255 HP #2555 only flows 170lph... which isn't a whole lot.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Heh.... I figured that bit out years ago... sorry guys

Here's another tidbit for ya... the return line goes into the canister...

well I can run below 1/4 tank no problem, but the pump can't keep up at my fuel demand.. either have to lower pressure or get a better pump.. I think the walbro might be faulty...


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Well, you've now reduced the delivered volume to the engine, so it's probably no surprise that fuel flow is insufficient. Still dissappointing, though. What (if anything) are the last generation F car guys using? How about the C5 Vettes? LS1 guys are pushing their engines above 400 hp all the time.

-->Slow

yah, I was kinda thinking that it decreased flow a little, but when I test ran it, it was less than 250ml/min. but the issue is the same as before, I might have found an inline walbro 255 I can try, lol.


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Would we be able to just drop in a fuel pump from a supercharged Wbody??? Only thing I know that might be a problem is the lines at the fuel pump are larger than the jbody




Jason
99 Z24
157hp/171tq
wheres my boost??

I talked with an F car friend of mine today and asked about fuel pumps. He told me guys with 500-600 hp LS series engines are using a gerotor pump from Racetronix which has the right connections for the small tube to the jet pump. If you read the page it looks like this is the answer.

http://www.racetronix.com/RX-F99-FPKG-2.html

-->Slow