EFI fuel pumps gone bad!! Help!!

[G's Chop Shop]

I have done a couple of LS swaps for a couple of customers. The last two have been LS3 swaps. For some reason my customers after spending high dollar for their engine it seems they want to cut corners or save in other parts needed yet are still very important.

I have used the Walbro 190 for these builds and have had problems with both of them. The first one is in a 68 Camaro with the stock fuel tank and the fuel pump mounted inline with the corvette filter(no filter before the pump). This car is occasionaly dragged and it would work perfect during the whole 1/4 mile (11.80e.t.-stock motor n/a) but after crossing the line and breaking it would starve for fuel big time to a point of not moving at all. It had to be turned off and switched on and off a couple of times before it would work good again. We also started noticing that the pump started to make more and more noice. Suddenly the pump gives out which led me to believe that the pump was getting clogged up or something. So I thought it would need a filter before the pump. We contacted our provider and they gladly sent me a replacement with a new filter to install before the pump. I install the new filter and new pump and it does the same thing and now it is dead again. My customer wants a solution for this problem and so do I but I am puzzled and do not want to make him spending money without fixing the problem.

The other one is a 68 C-10 with a LS3 swap. It has an aluminum fuel tank mounted on the back between the chassis. Same fuel pump with filter before the pump and the corvette filter afterwards with a return from it. This one starves sometimes when at full throttle going straight but starve more when cornering and turning. this one did the same thing.....became more and more noisy until it died.

Using the fuel pump formula I know I only need 40 gph to feed a stock LS3.

Is the Walbro 190lph capable of handling the needs of an LS3?

I imagine there is a problem with baffling in the stock tanks but why do the pumps die?

What is the best solution for the baffling problem?

Should I go with the 255lph?

[ohcbird]

The first step would be to make sure you have great electrical connections.

The second step should be the installation of in-tank baffles of some sort. I'd also reccomend some type of surge tank.

Although a 190 would support it, there is something to be said with switching to the 255, or one of the Aeromotive / Accel / Holley units (and many others)... at higher demands, you won't be working the pump as hard.

What pressure are you running them at?

[G's Chop Shop]

I am running the stock fuel filter/regulator from a corvette. it runs at 58psi.

surge tank?

[ccracin]

Most likely you are uncovering the pickup and starving the pump for fuel. Basically running it dry. Turning it on and off most likely is just repriming it. A surge tank is a separate bucket of fuel inside the tank that helps eliminate starvation due to fuel slosh. Running the pump dry alot is not good for it and is probably the root of your failures. I suggest you quit messing with inline pumps and go to this link.

http://vaporworx.com/

This company is owned by Carl Casanove who is a site member here. CarlC is his user name. There is a lot of tech information on his site. It's a great read. His stuff is cutting edge for efi retrofits!

Good Luck!

[Bsinclair]

is the Walbro 190lph you have designed to be mounted in the tank? ive ran into issues using these pumps externally. between slight cavitation and the cooling effect the fuel creates the pump would either fail or not pump enough fuel. you might also have a voltage drop issue causing the pump to run at a slower speed. i run the bosch 044 externally without any issues but its overkill and quite noisy...

[Fishin2deep4u]

Originally Posted by ccracin

http://vaporworx.com/

This company is owned by Carl Casanove who is a site member here. CarlC is his user name. There is a lot of tech information on his site. It's a great read. His stuff is cutting edge for efi retrofits!

Good Luck!

This is the same route I went. I agree with a surge tank without done type of module to keep the pump full of fuel.

Dave

[G's Chop Shop]

Thanks for the info, will definitely help.

[Steve Chryssos]

Vaporworx for sure. Siphons fuel down to the last 1/4", as it has an internal "surge" reserve. You can;t beat that OE grade design. Also, don't underestimate the need for a high quality fuel vent like the II Much Fabrication piece. Gph rating are useless if the pump must oppose suction due to insufficient venting. Many a pump has burned out due to poor venting.

I run both the Vaporworx setup and the II Much kit and could not be happier.