Fuel Injection Return Line Pressure?

[motorhead]

If there is typically 35-70psi of pressure on the feed side of the fuel system in an early GM-style fuel injection system; what is the pressure on the return side after the regulator?

I ask because I am planning out the fuel system for my TT EFI SBC build in my Monte Carlo and I would like to use the stock carb feed line ~5/16" as the system return. Not that the size (flow) is the concern, nor the material (25yr old steel). However, I am not overly keen on disconnecting the entire length of the line from tank to engine cross member to gain access to the clamps holding the rubber line which are currently tucked inside said cross member.

So if the return side pressure is approximately 15psi or less then the stock rubber line is more than suitable, no?

Yes, I am this lazy.

[TURBOPOWERED68]

the return line should NOT have any pressure at all.
If it has pressure it my because its undersized or it has a restriction somewhere.   

[daveismissing]

http://www.gnttype.org/techarea/fuelsystem/Returnlinearticle.html

[motorhead]

Thanks.

I also found this: http://www.mrgasket.com/Portals/0/downloads/mallory/pdf/Mallory_Instructions_troubleshooting_fuel_system_size_4110_4150_5250.pdf

[motorhead]

Thanks!
 

http://www.gnttype.org/techarea/fuelsystem/Returnlinearticle.html

Right. So using one pump that runs under 40gph I'll be less than 10psi and therefore SHOULD be safe. If I go beyond that requirement I can step up to a larger ID line. Heck I could run a larger 3/8" short line and link the stock feed and return lines with a y-block. I am such a cheap ass.

[SuperSix]

Yea - lazy prick - change out those lines!

[motorhead]

Budget build my friend...