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Mechanical: - Valves adjusted - Cam looks fine - Made new gaskets for oil bar Electrical: - Tail lights now work - Key now starts car - New alternator now charges battery On Deck: - about to practice Mig welding with C25 for first time.... holes in floor be warned!

The question depend on your age, Allow me to tell you to tell the story: Back in the early 90's when I built my car (71) IT HAD to have a cam, Had to!, at the time I worked right down the street from Camonics (NH CA) the owner, Ed Ninos (rip) talked me down into a "mild" grind of 262 duration. it was great!... Now lets fast forward ...that cam is a pita, it turned(?) the car to be a hooligans car, taking off from street lights is painful without gunning it,. there is nothing under 3000 rpm, at 4000 it explodes with power and pulls to 7k in a second flat. What can I say...I'm too old for this crap.

You're right except LOTS and LOTS of traffic! ? When its get cooler I might go out there and fill up!

Those are Appliance mesh mags and were very popular back in the day. I had a set that I bought a year or so after I purchased my Z in 74, had them refurbished locally here in Austin recently and sold them for $1000 with a set of BF Goodrich TA radials. I’m sure someone on this forum would be interested in your wheels. Sent from my iPhone using Classic Zcar Club mobile

Haha! Well if someone wants to set something up, I'd be happy to participate! Not sure I'm qualified, but I can twiddle some knobs and stuff!

Maybe, but an engine that runs closer to stoich requires a lot less maintenance and responds better to fuel inputs

I pulled the dash this morning, Man are 280z dashes easy to pull, I swear I had that thing out in 10 min. not so with a 240z. Actually I had completely the wrong idea about 280's, coming from 1970-72 240's I assumed 280's were heavy and fat with too much needless crap. But there so many refinements from the 240's, the rats nest of wire connectors up under the P/S dash on a 240 becomes 3 large plastic connectors that are easy to separate, there 8 tiny philips screws that have to be removed while lying on your back with your head crammed into the foot wells to get the heating push cables off on the 240, with the 280 it's 4 one handed clips. I have noticed many small refinements like these that I'm sure the line workers appreciated just as much as I do. Managed to get the dash cap off, a nice clean crackless dash is a wonderful thing but they are just so damn expensive, there has to be a better way to install a cap and make it look good. I've seen dash caps on Z's at shows that looked great, if anyone is interested we could start a separate thread just on caps and techniques to make the work and look better. The pic of the coolant control valve on the heater has a very A/C looking temp sensor on it, is this stock for a 77? This car does not have A/C nor did it come with it when new. Why such a complicated switch for such a simple function?

I agree that it is inherent to the design. That's why Nissan recognized the problem in 1973. I would assume that they had professional engineers work on the solutions that they proposed also. Just saying...they didn't publish that document for amusement. If those proposed solutions don't work then I think it's reasonable to look changes in fuel formulations. The fundamental problem is the same as for the EFI engines. Too much heat for the fuel. Many possible solutions, some not so pretty. A fun problem though.

You are right Zed hed. From now on I will refer to solving my fuel percolation problem. Others comments about fuel mixture variations from summer to winter etc. That may make some difference but only minor. And remember I started working on this problem long ago when you could buy leaded premium fuel at the pump so its something fundamental when it gets hot. As long as its below 90deg no problem. That was before global warming too,

Here is the interesting thing. The Z's don't experience vapor locking until the temperature get's over 95. So if the temp never gets higher than that no problem. My feeling is that the problem happens in the fuel bowls on the carburetors and in that small hose going to the jets, however, if the fuel is recirculated back to the tank then the fuel that goes to the carbs is cooler so it improves the margin. The other thing is that the Z432A may have ceramic coated exhaust pipes and a very good shield over the exhaust header. That would be a much better design although more costly for the mass market that the 240z aimed at.

The 432's exhaust manifold is stainless steel. It is not ceramic coated. You may have missed the point that the inlet side of the S20 engine - being a twin cam 'crossflow' design - is on the opposite side of the cylinder head to the exhaust side, so the exhaust manifold dos not heat up the carburettors or the rest of the fuel system in the way that it does on the L-gata engined versions.

The problem here is not "vapor lock". It's percolation. It's described in the Nissan document. The solution will come from the fine details, I think. As far as fuel goes, don't overlook winter blend versus summer blend. This has nothing to do with ethanol. It's a formulation change designed to make engines start faster and run better when they are cold, by increasing the volatility of the blend. For emissions purposes.

Here is the interesting thing. The Z's don't experience vapor locking until the temperature get's over 95. So if the temp never gets higher than that no problem. My feeling is that the problem happens in the fuel bowls on the carburetors and in that small hose going to the jets, however, if the fuel is recirculated back to the tank then the fuel that goes to the carbs is cooler so it improves the margin. The other thing is that the Z432A may have ceramic coated exhaust pipes and a very good shield over the exhaust header. That would be a much better design although more costly for the mass market that the 240z aimed at.

I'm most likely totally off base here but #1,2 and 3 runoff the front carb. May be a fuel problem. I would pull those plugs one at a time a check their spark. Good luck.

Some of these wires get hot and smoke? You have a lot going on there. The Start ignition system is different from the On ignition system, at the ballast resistor. I would check those wires closely.