just1n962

That's a pretty good idea I think I'll give that a go. I appreciate the help and I'll update when I've run the test

That's for the regulator that I bought off amazon that I don't have yet. What I'm currently running is the cheap pump with no regulator straight to the carb. I'll put the pressure regulator on if I switch back to the more powerful fuel injection fuel pump though. Hmmmm no I do not know the fuel pressure and flow at the carb inlet. How would I go about finding that out?

Well there is no return line... It's a brand new Holley 390 CFM.

The carb never actually consumes that much. That's how they measure the things but the carburetor itself has a built in regulator that opens and closes depending on how much fuel the carb needs.

Okay sweet. Yeah that's fine. The whole car is extremely loud anyways ha

Just a simple 4.5 to 9 psi regulator off of amazon. By bypass line do you mean a line that will allow fuel to return to the tank? If so then yes it does.

So I have my swap completed and I have been running a little 40 dollar pump from autozone with a 35 GPH flow rate and 4 PSI and it seems as though my holley 4bbl needs a good bit more than that... With the carb tuned I can now get it to idle nicely and I even was able to take it up the road a little but if you put your foot down a little and get the thing past 3000 rpm it wants to shut off. It's just not getting the fuel.. Now I know that I should have the 80 GPH flow rate pump but it's just so expensive... I still have my fuel injection fuel pump and just ordered a pressure regulator. Will the regulator be okay under the fuel injection pump? I'd appreciate any help here. (And please don't tell me how I should have stuck with EFI)

so new alternator?

Well you wouldn't think it would be simpler to just take out all wiring from my vehicle and replacing it with 260z wiring? I wouldn't be trying to mix and match the two. It would be either one or the other. It probably won't work out though and I'll just keep my harness. Oh by the way, my vehicle not starting was simply caused by one of the connectors on my alternator.... It was never really connected and the day after I drove it (before starting it that day) I decided to tighten down the bolt connection and that's what caused my wiring to go crazy and my positive battery cable to spark... I pulled that red/white wire off the alternator today and it went back to turning over normally..

Yeah I wouldn't want that. Okay will do! Thanks Steve. I'm also looking at a couple 260zs right now and might end up gutting the wiring out of one of those and just simplifying my life.

Haha yes I know. I figured you would be disappointed but this is definitely the route that I want to go.

Hello all. So I made the decision to ditch my ever failing fuel injection system in my 75 280 and do the four barrel carb conversion. (I have the Arizona Z car intake and holley 390 cfm.) Everything is hooked up and ready to go with the low psi fuel pump (I didn't forget to switch it), and there is no power going to my fuel pump now.. When I took all the fuel injection stuff out I removed the fuel injection wiring, computer, etc.. from the driver side so I don't know if that is what's causing my fuel pump to not have power or not? If anyone knows of a way to fix this I'd greatly appreciate it.

I want to thank you all very much I have just solved the issue with the fuel pump the right way! I followed your instructions and got everything hooked up right. Now my fuel pump doesn't seem to be doing the best so I'm gonna try to clean it out again or just have to get a new one..

Thank you. It has been a long year for sure. I would not recommend getting a complete rust bucket like I did ha but at the same time it makes you feel very accomplished.

There is a chance that I will be working a shift in atlanta on the 25th but I don't have any info on that just yet. Let's go ahead and shoot for that date and I'll keep you posted once I know more. I appreciate you helping me out here.

Yes I am. Oh yes absolutely! Have you done that engine swap yet?

Yeah I posted them to the Georgia Datsun page one time when I was thinking about cutting the springs.

There's a little before and after picture of the last year.

I pulled the engine and fuel tank and all the lines. The engine is completely rebuilt and brand new, I took apart the tank, cleaned it out, welded it back together and coated the entire inside and all the fuel lines are new. It's definitely not an issue of crud anywhere. Even with the fuel pump I took that all apart and cleaned every inch of it. This was a full on restoration. The only problem is that the car that I chose to restore had a previous owner who decided he'd take a "what the hell" approach to wiring this thing up when there were issues.

I'm definitely going to be trying out all of these diagnostics and figuring out more about reading the meter. And when I talked about turning the key I meant that I turned it all the way to start. The engine does turn over and it wants to fire but without gas getting to it she obviously won't. We got her to run for a second or two off of starter fluid.

None taken. I love the cutting, welding and engine rebuilding part of a restoration but I can admit that wiring is not my forte. I had my dad at the back end listening to and feeling the fuel pump for activity when turning the key and there was none until we connected another wire to the positive end of the fuel pump and the other side of that to the starter ignition switch wire. It was pretty weak but was pumping gas. Definitely not something that could be heard from inside the car. There's probably a better place that I could connect it that would give it more power but I'm not sure where that would be.

It was a pretty full restoration, rebuilt the motor and all and stripped most everything out. The ECU should be good. I bought it off of a running 76. I haven't seen any kind of ground for the fuel pump, is there supposed to be one? The black wire that goes to the negative just runs back up through the hatch along with the green/blue and to the hookup on the passenger side.

Okay this is great stuff. So I should use a voltage meter with one side on the black/white wire from the relay and the other end on pin 5 of the ecu to see if they correlate? Also, I have a 76 fuel pump relay and fuel injection harness. Does that make a difference? It's all the same connections I believe.

Okay so I've been restoring a 75 280z and it's so close to being finished but for some reason my fuel pump won't kick in when the engine is turning over unless I direct connect a wire from the fuel pump to another wire source that is getting current. Is it okay to do this? If so, where can I hook it up so that it's safely getting enough power, isn't stealing too much power from something else and won't burn up any wires or create a huge electrical problem. Oh, also, where would I hook the negative side to?