fuel line size for supercharger

[chargd72]

Found a paxton centrifugal unit that will be going on a SB 408.  I WILL be using a carburetor.  Probably CSU or Quick Fuel.  But I need to know what size fuel line will I need.  Will 3/8 do, or 1/2 inch?  If so, do I have to modify my own fuel sending unit or do they make them with the bigger lines?  I'm only shooting for 8 to 9 psi and the unit can push 1200 cfm.

[4cruzin]

I would think that 3/8's would be enough for that application . . . 

[chargd72]

Thanks for the reply.  Anyone one else agree/disagree?

[cdr]

i say 1/2,especially on a blower motor,if it leans out even for a millisecond its toast,better to have more than not enough.

[Dino]

Why take the chance?  Go 1/2"

http://www.ebay.com/itm/Dodge-Plymouth-B-Body-sending-unit-HALF-INCH-Fuel-line-return-1-2-68-70-/330893832478?pt=Vintage_Car_Truck_Parts_Accessories&vxp=mtr&hash=item4d0acf311e

[4cruzin]

I would of said 1/2 on a big block but still think 3/8 will be enough for the small block.   

[1974dodgecharger]

Ask cuda ken...

[chargd72]

Wow, that sending unit line is huge!  I would like to just do 1/2 and be done with it but most of the fuel pumps and boost referenced regulators I'm seeing are at 3/8.  And the pumps are flowing 140 GPH and the regulators can reference up to 65 psi.  It seems like 3/8 would be plenty??  Calling on Cuda Ken...

[cdr]

3/8 pipe thread,,,that is MUCH larger than 3/8 hose size. 3/8 pipe threads starts off .675 od before the threads are cut.

[chargd72]

3/8 pipe thread,,,that is MUCH larger than 3/8 hose size. 3/8 pipe threads starts off .675 od before the threads are cut.

Excuse my ignorance but wouldn't the ID of the nipple on that pipe thread that connects to the hose be 3/8?

[cdr]

yes & no,you can get different sizes,but the id of the fitting is what really matters. am sorry if i came across as a smart a$$ did not mean to do that.

thanx charlie

[chargd72]

No worries.  Consulted with some of my turbo Buick buddies and Cuda Ken.  The decision is to go to 1/2 to leave room for improvement.  My challenge now is to find a fuel sending unit for 71-74 B body with 1/2 line that has a return line.