All the info you should need.

DIY TRIPLE PUMPS on the quick and cheap - LS1TECH

People makeing over 1000 hp including E-85 users.

Whats the most RWHP put down by a triple 255 pump set-up - LS1TECH

 

My stock tank(40 gallon) with less then a 1/4(maybe 1/8) never had an issue at the track or beating on it on the street. That included on nitrous. Wasn't running crazy times but low 13s and 100 shot and never starved of fuel at all. Might not be perfect but something in my stock tank worked well at low fuel levels in huge tank.

I am not saying that a triple pump set up in a stock tank is going to work but all I am saying is that I didn't have any issue with a stock pump.

 

This is turning into an apples and oranges comparison. Yes triple pumps flow a lot of fuel and can be used in the stock tank. Im not sure if the geometry of the fbody tank is more condusive to keeping the pumps in fuel than the truck tank, but I bet it is. Also note Mightymouse does not use a bucket assembly, he just has the pumps laying in there, but I guarantee you he runs his full of fuel, making the half tank or lower argument a mute point for him, hence why he doesnt use a surge tank.

Your setup is a 400ish hp setup. There is a big difference in fuel needs from a 400hp setup using nitrous and a 700 or 800hp setup using FI. I know from my own experience I have pushed a single 255 to over 600hp, and I also know I have starved the pumps with dual densos and about a 1/4 tank of gas.

 

I am just trying to save mikegyver a lot of hassle if possible. Maybe there is something unique about his set up(such as truck tank) but I don't see his current plans as productive. It may work but I am confident there is a much more simple, lest costly way to get more then enough fuel for his needs.

 

It's alot easier for 3 pumps to empty a stock bucket than it is for 1 pump to empty the same bucket. ****, if you think about it for a second, the 3 pumps displace that much more fuel from the start, so there's less fuel in the bucket AT ALL TIMES. Less fuel to pump out of the bucket before they have to start pumping AIR.

 

Im gonna go on a limb here an say the surge tank has a return line back into it to control FP at the rail correct?
The engine would have to eat up close to a gallon in the surge plus what ever the stock pump puts in while fuel is being demanded under heavy engine load or WOT.I dont think hes gonna have a problem long as the plumbing/wiring is correctly configured between pumps.Btw. the stock pump will deliver a pretty healthy amount of fuel at little to no psi.Ill test one tomarrow so we can see what the number actually is.

 

I understand this. The point I was trying to get accross was that f-body guys are running 3 pumps quite a bit with out issue. It is something to atleast look into.

Possibly the truck tank is to differant, I don't know. I am just trying to pass on info that can hopefully be helpfull.

 

Thanks, I appreciate the concern. In my '00 tank, the opening is less than 4", I can't put even two of these pumps in if they are side-by-side. I've been through several fuel pump configurations, the first time that I put a physically larger pump in the stock bucket, I had to butcher the bucket. That is when I learned that you can't run less than 1/3 tank with a compromised bucket. With my stock bucket, I couldn't even put in one of these Densos without low-fuel problems.

All the stuff our heros on Tech do does not apply when it comes to the fuel tank. There is more area to the rear of the pump in our trucks than a whole f-body tank. The fuel pickup in a truck is uncovered from the gas sloshing rearward a lot more than you would think. That means that your relying on the contents and the design of the bucket heavily. I have been through the experience of having to keep the tank half full if I want to push hard on the gas pedal.

I have had two inline pumps fed by the in-tank. The Bosch 044 was inadequate, that might have been my fault since I was using a stock in-tank pump. The MagnaFuel 4301 (?) fed by a Walbro 255 worked for awhile until the 255 failed.

I've had either two or three Walbros fail. The MagnaFuel only runs about a year or two before needing a rebuild, covered under warranty. My main complaint about the MagnaFuel was the noise. I had to turn the truck off at the drive-up window. People walking beside the road always looked up at me, as if they were thinking "that's a weird noise".

So thanks for the thoughts, but you've been thinking about my fuel system for two days, I've been thinking about it for three years.

But please keep the ideas coming, that's why I started this thread before I have anything in concrete (stainless steel, )

 

Yep. It needs seven fittings: Supply and return from the main tank, supply and return from the engine, a drain, a wiring fitting, and a vent. The vent will be a 3/4" check valve with a valve cover breather for a filter. Cool. That information will be valuable to everybody.