Aerodynamic

Hi guys I apologize for the delayed response. @maltese the reason I want to change to just the electric pump with a regulator is for the consistency of fuel pressure flow. Through my current system the mechanical pump alone occasionally has times where it cannot keep the fuel pressure fully consistent which is obviously an issue. I am also redoing my fuel system to get rid of all the metal rails boiling my gas so close to the engine and I figured I might as well switch to the electrical pump only since it's already been properly installed. I just need to figure out how to power it. @datzenmike @datsunaholic Thanks for the input you two. I've been told to look for the aforementioned relays in the past yet they don't seem to exist on 260s. It also doesn't help that '74 was a weird year and I have an engine from a 280 in there lol. Guess I'll just have to keep digging for some kind of solution. Or just give up and seek out an auto electrician haha.

Hi everyone, I have a question about some stupid wires in my engine bay that hopefully you guys can help me with. Now before I start, I am aware of the many threads talking about fuel pump wiring on Z's but I've found no helpful information whatsoever. I am trying to convert to using only the modern electrical pump in the rear of the car, but I'm confused with the wiring. I have traced the wires connected to the pump all the way to the engine bay and they have continuity to the blue single wire in the photo: That's great and all, but where does this wire go? After poring over wiring diagrams I noticed that possibly the above harness of wires needs to connect to the starter and the alternator as "cutoff relays" however there is nowhere to connect them. My pump currently has no power or way of starting. Here is a photo of the wiring diagram. Any info would be greatly appreciated, as I honestly don't know what to do next and this seems like a frustratingly simple problem.

Looks like I need to get on it and find out what I've got. Datzenmike, I appreciate you mythbusting my claim. I've developed a mistrust for both my speedo and tach. It really doesn't add up now that it's laid out. 72240z, I totally forgot about my speedo cable replacement. That's probably causing problems as I replaced it with another cable from a Z without thinking. Like others recommended, I've just settled with driving slower and that's fine with me. I guess I'm off to find my diff ratio next... Thanks for the input everyone.

Hi everyone, I have a 74 260Z that has a swapped L28 and a 5 speed transmission (not sure the exact model). Anyway, my gearing is extremely short. Too short for the kind of driving I have to do every day. I'm slightly worried that running the car 5 days a week for an extended time at high rpms will eventually lead to problems. In order to even keep up with highway traffic around me I am running the engine upwards of 4000 rpm at times. As much as I don't like doing this, I am still barely keeping up with commuter traffic at about 65-70ish mph. It's also really loud and is murdering hurting my fuel mileage haha. Anyway, after searching around it seems that even Zs with 5 speeds and gears like 4.11 and such only run at around 3000 rpms at the same speed I am going. It seems crazy to me that I should be so high up in the revs. I'm not even sure if I have a valid question coming out of all of this or not, but I was wondering if anyone had any suggestions on gearing. I genuinely have no idea what I'm talking about. Am I the only one who spins this high on the freeway?

Good points there San Maru Currently I do about 16-18 mpg driving around on streets, but I waste massive amounts of gas at idle because my throttle plates won't close all the way. I would definitely consider switching to Mikunis if the opportunity came up, yet I feel that I can get my current Webers running fairly well in the next few weeks. If I can get to 20 mpg average I will be happy :cool:

Hey everyone, I am looking for the bulb and wire assembly for this light right here. The part is #9 on the diagram. Thanks

I do not have a carburetor synchronizer but that would probably be a good investment. Also thanks for the thread link! I'll be looking at that later tonight. I am also going to buy a new throttle linkage clip as I have discovered mine is mysteriously bent way out of shape. Hopefully I will have more time to work this weekend because as of right now school and work are killing of all of my free time... :geek:

Hey guys really appreciate the input on the ignition options! My coil looks like it's seen better days. I snapped a quick picture of the engine yesterday: I also have a picture of how the throttle sits in relation to the carburetor stop plate. The screws are't adjusted partially because the car has never idled properly haha. Are they supposed to sit this far away from the carb body? Or am I just majorly off in terms of adjustment? I honestly don't know how they're supposed to go :hmm:

Definitely going to buy a new spring tomorrow then. Ignition was actually something I was going to look into next as I feel I am not getting as strong a spark as I should be. I'm getting there slowly!

@ Datzenmike I do have a return line set up now, though it seems in that picture that a lot of the stuff isn't connected. I'll hopefully be able to upload a current picture of how the engine looks but I have work in a little while and its 103 degrees outside so I'll wait for now. Does anyone know the general tension for the return spring? Mine doesn't feel too tight now that I've checked.

Also @DTP, Just read a lot of your information and much of it I have not thought to do/check. Thanks alot!

Hey guys thanks a lot for the replies! Looks like I've got some work to do this weekend haha. I have tried tensioning the throttle return spring in the past and it left me with a stuck throttle! But I agree my spring probably needs replacing. As for the vacuum leak, I may have one at the manifold; gotta check back on this. I found an old picture of the engine bay. The fuel lines are set up differently now. I have a consistent 3.9 psi at the carbs. That black hose in the back going into the manifold is to do with the vacuum correct? I haven't really touched that thing since I started working because tbh I don't really know what it is.

Hey everyone my name is Edward and I'm new to the world of internet forums so bear with me! :frantics: In March I purchased a 74 260z that had been sitting in the back of my auto shop class in high school and was kind of fading away. I've worked all through the class and all of summer replacing everything many things and now the car is somewhat driveable. Here is the only picture I have: I do have one question however concerning my triple Weber DCOEs. I have gotten the car running pretty smoothly, not perfectly, but running well when up to speed. For the life of me though, I cannot get it to idle under 1400 RPM while stationary at an intersection or something. The only time I can get it to run at the proper revs is if I physically pull up on the throttle linkage with my hands and hold it there. If I let it go it seems that the carbs begin to leak through again and the idle climbs back up. I barely have to pull on the throttle linkage though; just move it slightly, about 1/8 of an inch. I've gotten the right timing, and the carbs tuned to run smoothly through the revs, but I cannot get the idle down. My question is do I have a leak somewhere, or how can i get the idle back down to normal? I can't really seem to find a straight answer around the internet, so any help would be greatly appreciated. The carbs have been rebuilt so I was wondering if they could be leaking out of the throttle plates, (There is a small gap) but I don't know if that is the problem. Anyway, it'll be great meeting some of you and learning about Z cars in the process!