just wondering cause i dont realy want to take my tank down to put a new one in it.. atleast thats what i think is wrong with the car. everyonce in awhile it wants to bog and when u go to stomp on it it just bogs more for a few seconds then it takes right off.. so if i can please explain how i can do it or if u dont think its my fuel pump please tell me what u think it is thanks..

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO 4th gen spoiler black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft
best 1/4 mile run of 14.44@ 96.53
this run is before the new exhaust system new sticky tires coolant by pass smog removal new runners new thermostat and new three core radiator since i would get to the line and be well over 220* aluminum drive shaft and vette servo

 

yea. you can add an inline before the filter under the driverside.

 

Just cut your fuel line before the fuel filter and put an inline fuel pump there!! Next Gen Parts (www.nextgenparts.com) sells a good one!! It's made by Accel and part number is SR38!! It's an Accel high-pressure EFI electric fuel pump, 45 psi rating, suitable for use up to 500 hp, mounting bracket included!

 

ok thanks guys so what is the exact procedure to do this again thanks for the help

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO 4th gen spoiler black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft
best 1/4 mile run of 14.44@ 96.53
this run is before the new exhaust system new sticky tires coolant by pass smog removal new runners new thermostat and new three core radiator since i would get to the line and be well over 220* aluminum drive shaft and vette servo

 

can anyone elaborate on how this procedure is done thanks a bunch..

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1988 firebird ws6 formula350tpi ascd ram air hood GT AUTO 4th gen spoiler black paint with blue pearl centerline champ 500 16x8 all around potenza 245 50 16 on front and 27x11.5 16 mickey thompson sportsman pros on the rear(real sticky!!) msd 6al box blaster 3 coil accel 8.8 race wires hooker shorty headers hooker cat back system pro shift light A pillar gauge pod and water temp and air/fuel ratio gauges autometer oil pressure gauge b&m mega console shifter vette servo custom ram air system with a 9" K&N cone filter tb coolant bypass slp runners polished plenum and runners 170* thermostat smog pump and a/c delete plus cat delete march underdrive pullies, tpis airfoil cvr high torque starter (love it) aluminum drive shaft
best 1/4 mile run of 14.44@ 96.53
this run is before the new exhaust system new sticky tires coolant by pass smog removal new runners new thermostat and new three core radiator since i would get to the line and be well over 220* aluminum drive shaft and vette servo

 

Beware! If you are running both fuel pumps you will loose octane points. I read an article a few years back and it was talking about the friction of a second fuel pump and how the second pump would distrub the balance of the fuel molecules and thus decrease the octane points. I think it is only 1 or 2 points. I run an auxillary fuel pump on my Z28 but i have a supercharger and so i hooked the pump up to a 30amp relay, and grounded it to the hobbs switch so it only comes on under boost. I went to the local oil filter shop, purchased a one way check valve and routed the fuel around the entrance of the pump with two Y valves, put the check valve between the bypass and there you have it!

 

what if i disable the stock in-tank pump and use a inline pump before the filter?whats going to happen

 

Using an external pump is only a temporary band-aid fix to the real problem.
A puller pump can only pull as much as the pump in the tank can feed it, although a puller does reduce the pressure the intake pump has to work against.
Chances are that the intake pump has never been changed in over 10 years and the sock is full of crap, thus reducing the pumps ability to flow correctly anyway, a puller won't help much for that problem.
I pulled mine with less than 50k on it and the sock was colapsed and had all kinds of crud on it.
I used to have a puller pump, I learned the hard way, now its sitting in the garage. They are also very noisey.
I say bite the bullet and drop the tank

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Rob
High Performance & Party page
Pics of my rides past & present and recent party pics!

89 TTA #426 20th Anniversary turbo 3.8 bone stock
79 TA 6.6l - all original stock
94 Silverado Tuned Port Injected
87 Grand National- lil' ole V6, 12.40 @ 108 w/1.79 60'
95 Trans Am Conv.- LT1

 

Anyone who says it's bad to pull fuel through the intank pump is full of crap!! Installing an inline pump with the pump still in the tank will not cause any problems! I would probably disable the pump in the tank like you were talkin' about tho!! As a matter of fact, my friend had a TBI car and converted to carb and is now using a Mechanical fuel pump and it's pulling fuel just fine through the intank pump that he left!! And a mechanical pump fulls WAY LESS fuel than an inline electric!! Don't listen to rumors and believe others who have had problems just because of their OWN MISTAKES or because they didn't know what they were doing!!

 

Sure it can help, but not to the extent of a good intank or intank double pumper like a Walbro. A puller will work if you are on the verge of exceeding your intank capabilities.
If you have a good scan tool and are exceeding the capabilities of the intank, hook up the puller and you can see that the puller works great at the lower rpms. But at every gear shift, watch as the A/F and O2s keep dropping off and getting leaner and leaner.
And if you still have the original fuel sock in the tank, you still have that problem no matter what! Pullers are basically old school and an easy way out temporarily IMO.

[This message has been edited by 2QUIK6 (edited April 17, 2001).]

 

Just because an inline pump will pull through an intank pump (if the intank pump is diabled) does NOT mean it's right...it's very ineffecient and you'll strain the inline pump. Besides a carb does not need much fuel pressure.

You can use an inline pump with your stock intank pump if you wire it properly and do not disable the intank pump. Do not just tap off the power supply to the main pump. Instead use a separate relay with its own dedicated power supply...this will prevent voltage drops from two pumps running off one relay and will keep up max flow from each pump.

I agree with 2QUIK6 though...just do it right the first time and drop the tank and put in a good Walbro pump. If you'd rather still run an external pump, at least remove the intank pump and fabricate a pickup (which you'll have to drop the tank anyway). Usually this kind of setup is used on high hp cars. Take a look at the Mustang crowd and see how their fuel systems are setup and you'll see what I mean...no band aid repairs there.

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1989 IROC-Z, ZZ3 shortblock with some bolt-ons.
13.20 @ 108.69, 2.2 60'

 

A GOOD inline fuel pump with last JUST AS LONG as a Walbro intank pump!! An inline pump is not a "band aid repair" as someone said earlier! Rather it's for us who PREFER not having to mess around pulling the tank down just to replace the pump! Everyone can stick with their crappy intank pumps and I'll stick with my inline that can be changed in a FRACTION of the time and will last just as long as an intank pump!!

 

Nothin' crappy about a double pumping Walbro 340 setup in the tank. Its not about which last longer..and don't forget about all the crap thats caked onto the fuel sock in the tank. You have to drop the tank to change it out anyway because even if you have a 10hp motor for a fuel pump, it won't pump crap if the fuel sock is clogged up and collapsed. If its the original pump/sock, I guarantee it is full of all kinds of stuff and would be real surprised if any pump could get anykind of volume/flow through it.
But hey, if you don't want to drop the tank and do it right, either using an inline or intank, than don't. But if you do and see whats in there, you'll be glad you went the extra mile to do it.

 

Well, I must agree with a statment above that says the aux. inline fuel pump does take the psi off of the intank pump. I'm not sure if you disable the inline pump fuel will flow at all? I hooked up a bypass to my inline fuel pump because my inline fuel pump does not allow fuel to flow through it unless it is pumping. So I hooked up a bypass to the pump, hooked it up to a 30 amp relay and grounded it to a hobbs switch so it would allow to flow freely when not under boost and then kick on when running boost. I think you would have to take the in tank pump out completely to allow the fuel to flow to the inline pump? Not sure about the stock pump but you will know once you disable the inline fuel pump! I would order a intank pump if unless you have a supercharger and can run the aux. fuel pump under boost. If you run an aux. fuel pump with the primary pump, you will loose octane points...aprox 1 to 2. This is because of things like specific gravity and friction.... anyhow, hope i can help

 

Been there, done both......

It's a hell of a lot easier just to put a walbro 255lph pump in the tank than it is to splice, cut, find a way to mount the outside pump, find a good place to put it.....


And an outside pump is the 'quick, easy way'???

 

NOS sells the Bosch made in line pumps made specifically to run with the stock in tank. These pumps can support 90+psi pressures. The stock pump does not negatively effect the flow of the in line pump. It sure isnt considered a "band aid" either. I ran over 550 gross h.p. with the 51764 NOS pump with my stock in tank hooked up. These pumps were designed with the stock units in mind.

Walbro makes some good in tanks also. I am going to try and run a Walbro with the NOS pump together with my next setup.



[This message has been edited by Kevin G (edited April 19, 2001).]

 

I agree with Craiger. I wouldnt stop running the intank pump with an in line pump. You would want to take it completely out if that were the case.

 

You're absolutely right...it's not about which last longer! It's about which is easier to replace IF it goes out!! I totally AGREE that the intank pump should be removed if using an inline but it doesn't NEED to be removed! If your intank pump goes out you have to drop the tank either way you do it...so save yourself the PITA in the LONG RUN and remove the intank pump, extend the pickup (cutting a V in the hose so it doesn't suck to something), and install a good inLINE pump!

Better to do all that ONCE rather than pull the tank down and change the intank SEVERAL times in your life! It WILL need to be changed at some point no matter what KIND of intank pump it is!! Of course if you don't plan on owning your car forever like I do, then you don't need to worry about it!

 

I replaced my inline pump twice in the 8 years I had one. Never had an intank pump die yet and can run 500+ hp with a single intank pump. It'll work either way, just whatever you think is best for your setup. You ewanted opinions, so here is both the pros and cons.
BTW, I have a Bosch inline pump I'll sell if anyone wants it, has mounting hardware and all, used for about maybe 50 passes on the track, as I'll never use one again

 

I never had an intank pump go, but it isn't as much of a big deal than people make it out to be. I'll put a damn 'add on pump' in your hand and race you by changing the intank.

My camaro has 160,000 miles and has the original intank (and the original filter, but thats a diff story)

Most yahoos that burn their pump out is because they are cheap and put just enough fuel in the tank to last the day... running between 1/4 and nothing and running out of fuel often. This KILLS the pumps, just sucking air half the time even if your not stalling is like.... not good.

Plus the tank offers protection from the elements and corrosion that destroys the wiring.

Plus adding a regular hose with a "V" in it defeats the 70 micron filter sock. Sure the regular filter will grab it but this is hard on the pump. One chunk of sh't in there and the pumps history since the filter always has to be after the pump.

[This message has been edited by JoelOl75 (edited April 20, 2001).]

 

Must be nice! I've had my car ALMOST 3 years...bought it with 120,000 on it and I'm on my THIRD inTANK pump! My car now has well over 200,000 miles on it!! I never once ran the car even CLOSE to empty! Now see, had I taken the intank out the first time and put on an inline pump it would have been MUCH easier for me to change the pump....and it probably would have lasted longer!!

Here's another scenario: Your intank pump goes out so you decided to buy another intank pump! You take the tank down and do all that other crap, replace the pump, reinstall everything...only to find out that you got a bad pump right out of the box (it's happened to me)!! Now you have to drop the tank AGAIN and do all that crap again....what a PITA!! If you had installed an inline pump and found out it was bad out of the box you just get under the car, unhook a couple wires, undo the pump from the line and go back and exchange it.....hook the fuel lines to the new pump, hook up a couple wires, and you're ready to go!! Just a FRACTION of the time it would take you to do that with the intank pump!!


Like the other guy said, now you have the pros and cons....so in reality it's up to you what you want to use!!

 

Some of these comments are a little off the main subject but...........

Using the intank pump with an inline pump is a good thing. It will work like a lift pump in a diesel system. A lift pump's only job is to bring the fuel to the actual Injector pump that builds the pressure for the fuel system.

Pulling the tank on one of these cars is not as hard as everyone says. I remember the first one I did. All the other mechanics at the dealership I was wrenching at were telling me it was gonna be a Bastard but I had the entire job done and out of my stall in about 2 hours. Granted the exhaust was pretty new and the muffler came off the intermediate pipe really easy, but it still really isn't that hard. I would say that you could do it in the garage with a floor jack and jack-stands in about twice as long as it takes in a shop with a hoist.

Also, ever heard of a Hot Wire Kit? I can't remember who sells it but you can do it without a kit very easily. I think all the 'kit' is, is a thick (8 guage?) wire that you are supposed to run directly from the battery to your pump so that it gets more power potential when turned on. The factory GM wiring for the fuel pump is less than ideal for higher HP engines that need more fuel. My TTA buddies all do this on their cars right away.

my $.02

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Matt

1987 GTA L98 MD8 GW6

"Stop Lights timed for 35Mph are also timed for 70Mph"