is a fuel return really needed for dual 45dcoe

[totorote27]

I think you will face pressure spikes at idle !

Do you mean Pressure spikes without a regulator?

I would assume that the hollley regulator can be used with the carter fuel pump ?

[BOBLOOK]

I think you will face pressure spikes at idle !

Yes !

Do you mean Pressure spikes without a regulator?

Yes

I would assume that the hollley regulator can be used with the carter fuel pump ?

It will work fine

[3trolla79]

Why do u need to put a regulator on the return... Just wondering sorry I don't get the picture ..doesn't the return jus dump into the gas tank??? Sorry if that's a stupid question .....just wondering because I have the same issue with stumbling but it's just a simple 32/36 weber but I'm looking into puttin on these 40s I have off a 93 1100cc gsxr but I need to wait till I get the jet kit or atleast a manifold made up for it but I understand I need them to be at an angle and I need a electric pump with a regulator according to @hemiluvs build???

[baldo]

There are two way regulators but they are old ones. I have a purolator one. Have not seen one in quite some time, but Im not really looking for one either. Anyways all I got was yes we do need a return line, awesome! Where do we put it? Do we need to custom the tank or use lines in the car already?

[BOBLOOK]

The majority of car have the Oem return line !

[baldo]

I have not run a stock anything in over 15 years! I keep asking the same question. In the gas tank are 3 lines, 1 I am using for my non oem fuel pump on the left. Now the other 2 what? Which one is the return line the middle or the one on the right? Thats all I need to know to figure out the rest.

[baldo]

The reason is I was going to install a line and get rid of the stock one. Ill figure it out.

[skunk1]

i run a bank of 4 41mm keihin fcr's, i had the ability to change the float seats from a few different sizes. in the motorcycles they came from some had fuel pumps and some gravity fed. the problem was they only like 3.5 psi, so needed a regulator. it is my understanding you can easily over power the float seat at idle so any carb needs a regulator, but on the same note a return should allow it to not over power the seat. the problem is "x psi" (3.5psi for me, 5psi for most webers, up to 9psi in some stock carbs) is maintained with the regulator, but flow rate is not controlled by the regulator; so when regulating down you can get a drop in flow rate at wot. my fix was to set the regulator to "x psi" at wot. this should net you the flow at high speed, but the return should not allow it the "bleed" over. the other thing was my return line was choked down, like a 1/4" stock line. so it too had a effect on standing pressure and wot pressure in the line as well as flow rate. the easiest way for me to check this was, lol, driving with the hood off and observing the pressures in the lines at the carb and return at all engine speeds. i agree you need a return, not only for the fuel to circulate, but also so you dont burn up your pump. stock size pumps dont have the flow rate required for side drafts in my opinion.

[BOBLOOK]

I have not run a stock anything in over 15 years! I keep asking the same question. In the gas tank are 3 lines, 1 I am using for my non oem fuel pump on the left. Now the other 2 what? Which one is the return line the middle or the one on the right? Thats all I need to know to figure out the rest.

Line should be there i know but to tell you were exactly i can't don't own an corolla anymore !

By the way some car have the return line on the carburetor itself other on the fuel pump

You can see them both lines on the fuel sender