Fuel line size (help Jody)

[69x22]

I am running a F1 Pro Charged 417 stroker. The fuel pumps are 2 Walboro 225s, mounted separately in a SS tank. Plans are to run the second one on a micro switch off of the accelerator. Questions are what size supply line and what size return. I will be running a Aeromotive bypass valve up by the engine.
Also when 1 pump is running what will keep it from back flowing into the second one? Do I need to install some sort of check valve?
Thanks

[speedjohnston]

It depends on the amount of boost and power you plan on making. I haven't done the fuel system in mine yet, but I did purchase my procharger stuff through Steve Morris who is the procharger guru. I believe he told me to run a -12 with a -10 return but if you gave him your combo there wouldn't be a better person to ask. He sold Steve Morris racing engines and you can find him at New Era Racecraft. Check out his street radial giant caprice wagon running 7.50's at 190+. http://www.neweraracecraft.com/

[speedjohnston]

Aeromotive used to have some diagrams of running two pumps and the whole combo with filters check valves etc. I took a quick look and didn't see them but I did find the valve you need. http://www.aeromotiveinc.com/products.php?prod=39

[64duece]

You'll need to run a -10 feed and return minimum. -12 feed would be abit overkill but, this doesn't hurt when it comes to fuel system design.

Your second pump needs to have the check valve on the head end as stated. You'll flow fuel back through it without one.

[LSXZ28]

In addition, you may want to run the second pump with a Hobb switch instead of off the accelerator - alot easier to tune when the second pump comes in only under boost. I have tuned several LSx cars with dual pumps and this type of actuation and it works great...

[camcojb]

good info above, #10 minimum inlet and a check valve for the second pump. I like the hobbs switch idea for the second pump, but I've run it off of tps also. Nice looking setup.

Jody

[69x22]

Thanks Guys.