JonnyC

iTrader: (19)

Awesome, thanks for posting this up!! Will come in handy in a few months.

A few questions though...

1. Would I able to be able to go back to the stock fuel pump after this modification? No big deal, but if I sell the car I would have to be sure to let the new owner know that they would need to get a Walbro pump if the current one fails.

2. So the drilling of the swirl jet is a replacement for what Turbonetics does - removing the swirl jet and drilling holes in the side of the can?

fishclub

iTrader: (4)

What will happen if i don't drill anything just replace the pump itself?

Ahsmo

iTrader: (13)

"its no big deal... basically without doing those the regulator cannot do its job. what is happening is your car will experience high fuel pressure when the engine isnt using much fuel. it can be tuned around but the problem is its not consistent because now the pressure will move around based on voltage and other small factors that are inconsistent. if your car has any trouble idling clean, then fix it... if not i wouldnt worry much about it."

Quoted from Charles's PM to me.

Everybodywildou

iTrader: (32)

I checked Lowes and couldnt find this small bit. Anyone know where I can find it?

phunk

iTrader: (21)

the regulator mod will have no effect no matter what pump is in there, it just increases the outlet oriface size cause it was never intended to support so much flow. luckily, the rest of the regulator can handle the walbro decently, so it wont matter either way.

after modifying the swirl jet to support the additional flow... if the additional flow is taken away and a stock pump is put back in, there may not be enough return system pressure to properly operate the over-tank siphon and the car may or may not experience running out of gas when it still has a half tank as it did not siphon the other half over. the venturi siphon is delicate and requires a certain ammount of pressure in the return system to operate... opening that oriface relieves some of that pressure and therefore it will not be as strong as a siphon... if it will still function fine, or not function at all... only someone trying it could tell. just tell the buyer that should the pump ever fail, to replace it with the same model that is in there, and the GSS342 part number is physically stamped on the pump so even if they dont write it down, when they remove it they can see what to replace it with.

2: yes, this is different than the turbonetics mods. the turbonetics mods kill the swirl pot and turn it into a mini baffle by taking away its natural method of filling and they put holes in the can, and they reduce the function of the siphon by removing nearly all the return pressure. the mods i show you to do will keep your system exactly like stock, only it has a higher capacity pump. dont bother going back to stock... i dont think you can buy a stock pump without the entire assembly anyway... so if the next owner DOES try to go back to stock, everythign you modified will end up getting replaced anyway.

phunk

iTrader: (21)

if you translate the size to a fraction it may be easier to find. also, it doesnt have to be exactly .070. i have heard of people going as large as .100 without a problem. I say .070 because i personally always used a .068 drill bit and did it by hand, which isnt straight and probably ends up at .070... i know for sure that that works, that is what my car has had for years... so that is what i recommend. if you end up going to .100 you are probably just as good, i just wont say it personally cause i havent personally gone that large.

imonlykidden

iTrader: (11)

Good..now i can fix mine.

JonnyC

iTrader: (19)

Thanks phunk, i was mainly curious more any anything. I will be sure to follow your steps when I install my pump in a few months.

weslutes

iTrader: (7)

You think larger washers should work?
My swirl jet is drilled pretty much as large as you can go & it seems o.k. for now. I haven't tuned for big hp yet though.
7 hundredths?
Am I just trippin'?
It's late/long day

fishclub

iTrader: (4)

Phunk,

As your instruction metioned to drill the swirl jet, is the hole you drill have to go through the the little jet nozzle? And if you view from the top of the yellow swirl jet, are you suppost to see the tip of the drill bit stick out in the little chamber? Secondly, I drilled through the regulator's first layer sheet metal, once you past that layer, is the drill bit suppost to feel very lose to travel in and out? I did't drill all the way down, but after the drill bit break in, it felt lose immediatly? Please let me know if I do anything wrong.

Thanks

phunk

iTrader: (21)

the regulator sounds fine... i also noticed that there doesnt appear to be anything immediately behind the sheet metal and once you drill it, the bit will go in a ways before hitting anything else.

as for the swirl jet, i have a picture on the page shownig the drill bit inserted into the hole that you are supposed to enlarge, it sounds like you got it right.

fishclub

iTrader: (4)

Thanks Phunk, Hopefully everything turn out right. So, without a fuel pressure gauge, is there any other way to know the fuel pressure?

phunk

iTrader: (21)

negative.

PTP sells an adapter that bolts onto the back of the driver side rail. You can probably pick up that, i am guessing its around 30-40 bucks... and pick up a mini 1/8 NPT pressure gauge for about 20 bucks, and then you would be set.

JonnyC

iTrader: (19)

Alright, so yesterday I followed this procedure to install my Walbro and I must say the directions you put together are awesome! However, I have a question...

On the bottom of the stock pump there is a piece of rubber between the pump and the plastic clip that holds it in. Does this get discarded? I don't see it in any of the pictures, so I assume it's not used. I filed down the clip just a little bit, and was able to snap it on there. It was a little easier than I thought it would be, but it still fit on there very snug. After I got everything together, I turned the key to ON and hear the thing kick in (wow it's loud). Saw fuel pressure of 35 psi or so. Turned off and back on again, then "Pshhhh" - it sounded like when the pump kicked in a hose somewhere popped off and I expected fuel to be all over the ground. Nothing, anywhere though. So now when I turn the key to ON, the pump kicks in and I'm only seeing like 3 PSI ?!?!

I did an injector install at the same time, so there is going to be a ton of air in the system. Think the cap popped off the pump, or is this just a result of the air in the system?

- Jon

phunk

iTrader: (21)

i personally discard the rubber bottom isolater.. some people prefer to keep it. i dont know, i have had the same walbro in my car for a few years now without any issue.

try priming it a few times and see if it builds up pressure. if not, something popped off! the air should cycle out within a few primes.

JonnyC

iTrader: (19)

Man, i really don't feel like taking the pump basket out again

Once I get everything put back together I'll try cranking it over a few times to see if the system builds up pressure again.

Thanks phunk.

05Z33

iTrader: (11)

What size drill bit do you use for the swirl jet?

JonnyC

iTrader: (19)

Well, turns out it was just air in the system. I pulled the fuel pump basket again and everything was intact. Put it back in and had the same issue again, with no fuel pressure. Got the motor back together so i just cranked it over a few times, and the fuel pressure is at about 42 psi now

SweetDreamZ

iTrader: (6)

is this site still hosting the directions? I can't get it to load...tried at work AND athome....

QuicksilverZ33

iTrader: (34)

^ +1 I was looking for this the other day as well.