Swapping to injection, questions

duct-tape

duct-tape

Well-Known Member
Site Donor
Messages
522
Reaction score
152
Location
Atlanta, GA
Next on my list for the b34 project is the fuel.

How should I adapt a pump? Is it an inline type setup or do I need a pump in the tank? Also, will I need to run a return line?
I could find much in search, so any/all info would be great
 
You need both, an in-tank pump and a return line. I’m not sure how the e3 tank differs and what pump you would use. In an e9 most use the 318is pump and e28 sending unit, the pump pickup needs to be lengthened however. I bought fuel pipe from BMW and modified it as a return line, 74 and later cars used a return line even with carbs.
 
HB Chris said:
You need both, an in-tank pump and a return line.
74 and later cars used a return line even with carbs.
Click to expand...
These 2 things. My car is 72, so I'll have to work out the return.
Does it HAVE to be an in-tank pump or can I use an inline pump?
 
“ These 2 things. My car is 72, so I'll have to work out the return. ”

The 318i pump setup takes care of the return line.

Unless you have a csi tank .....
 
You need 3 1/2 atmospheres of pressure so 50 pounds with a return line with a regulator. There are other aftermarket in tank pumps, Don was using a Mustang pump at one point.
 
I went with this setup from Tanksinc.com on my 72. I also did the POR-15 seal process. All in all it was a fair amount of work. I still have a ways to go before the car is running again but hopefully this setup works well.



IMG_20200806_204330158.jpg
 
Last edited:
I don’t think the issue is the return in the tank, it is finding a return pipe itself. They were hard to find for an e9 seven years ago, don’t know about e3.
 
I think I will just use old fashioned galvanized steel fuel likes bought at a parts store and use couplings where needed.
 
e9 return lines are avail and cheap.
great deal
e3 not available as far as I know.
off to the Parker store for their easy bend fuel pipe.
 
From the engine bay to the diff it follows the fuel pipe
A36C47BD-6A85-4FB4-BE78-96CB1267D9AF.png
 
i was looking at the sending units with the return line built in, but they are specific to the tank, because of length. I may just modify my sender and add a port.
I'm not worried about finding an OE return line, I'll just make one
 
You must log in or register to reply here.
Back
Top