sparrow6190

richer all the way up to the top, smoothly*

not really... you are just insisting that I don't understand. it was running lean, at choking out. im about to install a potentiometer inline with the temperature sending unit too because of the mods ive done

yeah just sounds like dirt, rust, and old... take a wire brush and go to town

any update? every time I ever had an ignition problem it was a "doh!" moment , its actually quite simple on every year except they made every year a little different...! ugh oh, and as for running a zx dizzy and having problems like you said earlier (the autos have a 9* t-bar, and i think lighter springs, manuals have the 8.5 and a bit stiffer springs i think, but ive seen all different kinds...), the closest zx dizzy to an actual 240Z dizzy you could get would be an automatic with no vacuum advance hooked up, but you still would have very minimal mech advance so it would not be any sort of upgrade from the original points , not if they are working fine.

I wish I still had the little plastic cap on mine.... it fell off so it stopped working right, good thing my BCDD is working... have you checked that? They don't have them on the zx's, I wonder what they use.... I've actually just been thinking about taking it off...,

yes it effects the entire range not just the idle entirely

they used way too much vacuum and not enough mechanical advance after the 240z in order to get better mpg. Vacuum sucks, at least a lot of it, and it REALLY sucks because it doesn't work. I personally want to just order a dashpot from summit with only like 10+ vacuum advance on it, that would match up nicely with my timing, 16-18btdc and 36-38 mechanical total by 2500rpm. I can only imagine how amazing she would run on the highway at with a low advance vacuum dashpot.... Stock ain't better, they don't make it anymore for a reason

Sounds like your vacuum advance is takin a crap, they suck I disabled mine and drilled out the t-bar and added lighter springs... much simpler and very effective... As for running rich or lean, at high rpms? low? After 30+ years these afms DO need to be adjusted... its just a spring, and adjust them WORKS WONDERS. You can replace perfectly fine parts all day with new ones... or just adjust a 30+ year old EFI system.... its ancient, and kind of like a carb as is it does get dirty and takes mechanical readings on volume and meters air with flaps and bypass n such... The bypass screw is an actual bypass screw, so the more it is closed, the more air is actually pushed through the meter, resulting in a richer mixture. So enriching or leaning out the mixture take this for example - I was running lean at top, and much better at lower rpms IF i tightened the bypass, because it has a great affect at idle and has less effect for the more air that is actually being pushed through and metered at high RPMS with high air flow. So all i had to do was turn the spring CCW inside the afm about 4 teeth or so, then open my bypass more for a leaner mixture at idle and up. (BTW, do not close your bypass screw all the way doing this, you very well may damage your afm and flap because the bypass screw acts as an escape at rapid deceleration... or your flap goes FLAP FLAP FLAP and bounces around, which is a no-no)

jeeze, everyone always has these crazy ideas why, and how things work. the idle bypass screw controls how much air goes past the flap, and not through it, thus at idle you wont have much air going through so the small hole has a great effect, and it DOES effect your entire mixture all the way through, it is a BYPASS, as it it bypasses the flap, the more you have it closed the richer your mixture is because it is actually being forced through the flap.. so yes, its not just as simple as "just idle" I'm not sure if it was answered yet, but it just is an old car with an old mechanical electric fuel system, STUFF GETS OLD.... but all you need to do it take your AFM cover off, losen it counterclock wise around 4 teeth, after 30+ years you people REALLY should expect something like that.... I like my AFM idle adjustment screw set at about 2+ full turns out from bottom now. This is the only real way to richen up your mixture all the way through, unless you get a potentiometer and hook it in line with your temperature sending unit. then you need to set your idle bypass and idle adjustments until it pulls smooth all the way from stop to 6k+.. you can use common sense to a point but an A/F meter would be amazing... I absolutely love(HATE) how everyone thinks of these outlandish ideas, so intricate and silly when its always something so simple, like a clogged fuel filter or crimped line, an old spring, a lose connection or a broken wire that would have been easy to trace. After upgrading to headers, 2.5exhaust, xr3000 ignition, drilled t-bar with lighter springs and no vacuum, and lots of mechanical advance this is what I needed to do, and now its a total beast, for cheap-o-hell too...

Where did you buy those springs? Were they specifically for the Z seats or just generics that matched spec?

oh my bad, i read the posts but must have missed it, thanks

Thats a real shame, I have the two cut outs under the deck and I can't use them! Im sure there are some more tools down there too... I hear some things slide around when im driving a little too fast. What is the main difference in the raised deck besides its obviously raised, did they do it for any good reason? I might try and modify the deck when I have the car apart before I take it to the paint shop and transplant my old lids from the 75' in. I just can't deal with the fact I have all that open space I could be using!

In my 78 I was digging around under the rear deck compartment a while back and found an old breaker bar and the original tool bag up behind the seats sticking out of one of the tool box openings behind the passenger seat, but there is no cut out for a hatch in the deck or in the carpet. Ive been looking for confirmation that Datsun quit installing the boxes in later z's but I can't find any help. Is this the norm? And does anyone know where I could get a kit to install the boxes? In my old 75 280 back home it has the metal lids and everything so i was confused when there werent any on this 78.

im just glad my clock still works great, I didn't even know untill i decided to set it one day and it was still 100% accurate a week later!

lolz im bout to order some illuminas i think, they seem better than the HP's, but i dont really know, i do like the adjust settings though.... thats neat!..