figured it out. engineered it. building it maybe this weekend. entire cnc'd unit that will drop in and replace the factory plastic pump assembly. the only thing that makes this project difficult is siphoning and tank leveling. well, after a conversation with someone today sparked some serious motivation in me to complete the engineering... and i have spent the last several several hours on the drawing board and it hit me right in the face exactly how this can be possible and actually very easy... cant believe i didnt think of it before.

its simple enough that it will not take long at all to build. there is a red 350z down there at jotech that has this parts name written all over it I think a car in PR has been on my case for one of these as well i want to see some 700+ rwhp street car 350z!

 

Wow,

Sounds awesome. Please let me know if it works.

M

 

sweet keep us updated man

 

Congratulations Charles, I'll be giving you a call next week.

Derek,
-DSport

 

AWESOME!!....Keep up the good work Charles

 

Nice work Charles!

 

Charles lets get this done by next weekend if not sooner, a working proto type. Send me a PM with the new developments or just call me. I have been thinking of some stuff also.

 

phunk,
You already mentioned you're hitting the drawing board with this, so good luck..I won't be going FI until summer but I am getting my supporting mods together and this is the system I'm considering running, and it may be an option for you to consider as well..The concept is really nothing new as it's been used in racing for a long time. I think it'll save a bit of headache trying to piece a twin in-tank design together and still keep the OEM function.

I've basically come up with a twin in-line walbro system that'll utilize a surge tank roughly 2-3 litres in capacity. The stock fuel pump assembly is left unmolested other than to supply fuel to the surge tank. The twin pumps of course will feed from it as well and supply the fuel to each rail on both ends. The return on the rails will be tapped in the middle of the rail and follow the traditional route back to the surge tank. The tank will also have a return line running to a tapped fitting on the stock fuel assy.

Sort of like this:

 

Yes!!!! my harassment is finally paying off. This is probably the best news I've heard this Xmas.
Congratulations Charles, I'll be looking fwd to your set-up.

Carlos,
626whpG35TT, PR

 

Glad to here you are almost done. Ive been waiting for this for while now and will be ready when its out

 

should i have my name down on the waiting list?

 

thats awesome keep us updated!

 

this setup is very common in many high hp imports here in PR, my only concern with it is the noise produced by a twin or even single pump out of the fuel tank. I had a similar setup on my SupraTT and it was too much noise for daily driving (but it works )

 

+1 I would have to have an in-tank setup just because of the noise factor.

 

Yeah, I don't know just how loud the walbro's would be compared to say aeromotive or weldon pumps. I've heard those pumps running and they are loud, even more so if you hard mount them without rubber insulators.
The other option would be to fabricate a little larger surge tank and drop in dual in-tank pumps. A lot of space behind the drivers seat (stock woofer location) to fit a nice sized tank.

Anyway, don't wanna hijack the thread..

 

I will not be using an external surge tank such as you pictured. I have developed a way to keep everything inside the tank just like stock, only with 2 pumps instead of one.

The additional complication of external lines and hoses and mounting a can are just not up to my way of doing things. I could have done that last year, but I havent ever liked that idea.

 

I want to see pics like an idiot,pleaaaaseeeee

 

The step up for the fuel pump is the same set up we use in the formula one race boats. If you pick up from the bottom of the tank you can replace the first fuel pump with a check valve. The only trouble is that we had to use 1/2 inch inside diamater fittings. We used a red holly 6 psi pump to feed the surge tank an a bosch pump to feed the injecters. The fuel system is the same that you find on a mercury 2.5 outboard motor. You will be able to hear the pumps running. After we installed this system we never had any fuel problems and our boat ran at speeds close to 136 miles per hour. Note you have to put a filter in front of the first pump or it will get full of dirt and starve the surge tank for fuel. The first pump must pump more gpm than the high preasure pump or the system will run out of fuel in the surge tank. We also put a filter infront of the second pump as at one time we ran both pumps with no filters and had many pump failures. Since the pumps are external to the task I would also put in a rollover switch, for incase of a accident it would turn off the pumps in case the car turned over in an accident. Note the fuel lines on the suction sides of both pumps should be 1/2 and be at least 250 psig lines or they will cavitate and starve the system for fuel under high loads.
This lesson was learned the hardway as we were leading a race and our boat would just shut down on us and for no reason restart a minite later and repeat the shutdown over again . Our engine made 387 hp on this set up, on 56 psig of fuel presure. We flow tested the pumps with the tank and it dilvered 273 liters per hour of fuel ( no injecters at end of high presure pump open hose end) 60 gph.
I hope this helps you with your set up design.

Formula 1 Boat # 79 Novak Racing, Toronto Canada

NO LONGER RACE THE BOAT, JUST DRIVE THE 350 Z.

 

Just in time! Awsome!

 

I would change one thing on your drawing. The discharge from the first pump should go into the bottom of the surge tank and not the top. Our engine used 27 gal per hour and we never ran out of fuel.
0 to 100 mph in 4.0 seconds ( race boat). The system works perfectly as it removes any air out of fuel system before it can get to the engine.