Aftermarket (Walbro) Fuel Pump

I picked up one GSS341 to run with my stock pump, you can compare the flow rates at the link below. I purchased mine from Lar, PHR also sells a higher flowing Walbro for a little more money.

Walbro

also

Rates

Melvin

im gonna jump in on this thread and ask something...

is there any single external pump that will supply enough for around 650-700 rwhp by itself? if so which one and how much. thanx.

i am worried about getting twin stock pumps for my single because it was discussed in another thread that if one failed, then by the time you figured it out, (a high boost run) your engine could lean out and blow.

Andy, that could happen to any pump....at any given time, you could also have a blow out at a high speed run. Not putting your concerns down, but anything could happen at any given time.

But to answer your question, if you go to the MKIV tech articles you'll find that Nick used an external pump. Not quite sure how much the pump flow but I'm sure with the name of the pump you can find out.

As far as twin stock pumps, if you look at the test, when the stock pumps are operated in 12v mode, they draw quite a bit of current compared to the Walbro at 12v. So I plan to run my stock pump in the switched mode and the Walbro in 12v mode.

Hopefully someone with more experience will chime in....

Melvin

gritsak said:

is there any single external pump that will supply enough for around 650-700 rwhp by itself? if so which one and how much. thanx.

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A Granatelli Signature Series EFI Fuel Pump would flow enough for 650rwhp, but is very, very loud. External pumps also tend to overheat in rush hour traffic (no air flowing over them to cool them off).

mello2 said:

Andy, that could happen to any pump....at any given time, you could also have a blow out at a high speed run. Not putting your concerns down, but anything could happen at any given time.


Melvin

Click to expand...

but if this happened with only one pump, then wouldnt the car just die, instead of with two pumps if one quit then it just wouldnt get enough fuel and then run lean?

Good point. Not sure what would happen though.

Phil gave good info on the external pump...

Melvin

Well, my question was about REPLACING the stock pump completely with just a Walbro upgraded one. Based on the opinions of others, I ordered an FPD003 kit which is for an earlier DSM, but comes with the GSS341 pump . . . should work? This will flow more than the stock pump, right?

lilviv said:

Well, my question was about REPLACING the stock pump completely with just a Walbro upgraded one. Based on the opinions of others, I ordered an FPD003 kit which is for an earlier DSM, but comes with the GSS341 pump . . . should work? This will flow more than the stock pump, right?

Click to expand...

lilviv, if you look at the chart you'll see that a single Walbro will flow almost as much as the stock Supra pump but at less current ,sounds to me like the Walbro is more efficient, using dual Walbro's will get you almost twice the flow of a single stock pump using less current...

In my setup, like I said, I'm using a stock pump plus a Walbro, the stock will work in the switched mode and the Walbro in 12v. I've heard of people using 2 stock pumps because they say the stockers last longer than the Walbro. But how long the stockers would last running at a constant 12v drawing the kind of currnent they draw is another thread.

I would not recommend a single Walbro making the kind of power you're making, plus you plan to upgrade you injectors correct?

Well, I do not plan on upgrading injectors . . . and, I figured I didn't need to 'cause my Nitrous system is injecting fuel before the throttle body mixed with Nitrous Oxide?

Also, where is this chart you are referring to? You don't think it has a higher flow capacity and/or reliability than the stock one? Thanks.

mello2 said:

lilviv, if you look at the chart you'll see that a single Walbro will flow almost as much as the stock Supra pump but at less current ,sounds to me like the Walbro is more efficient, using dual Walbro's will get you almost twice the flow of a single stock pump using less current...

In my setup, like I said, I'm using a stock pump plus a Walbro, the stock will work in the switched mode and the Walbro in 12v. I've heard of people using 2 stock pumps because they say the stockers last longer than the Walbro. But how long the stockers would last running at a constant 12v drawing the kind of currnent they draw is another thread.

I would not recommend a single Walbro making the kind of power you're making, plus you plan to upgrade you injectors correct?

Click to expand...

mello2 said:

I picked up one GSS341 to run with my stock pump, you can compare the flow rates at the link below. I purchased mine from Lar, PHR also sells a higher flowing Walbro for a little more money.

Walbro

also

Rates

Melvin

Click to expand...

The links are above, click on Rates and Walbro, they are both links

mello2 said:

The links are above, click on Rates and Walbro, they are both links

Click to expand...

Man, does this mean that I will be worse off than a stock pump with the Walbro GSS341? Sigh. =(

I got it for a little under 125 dollars shipped and after tax.

Mohd sent me this URL:

Fuel Pump Info.

On there are two separate charts, one has the GSS341, and one has the stock Supra fuel pump.

Can someone formulate decent opinions based on those charts?