Zed Head

He gave details in #395. Phones... Still fascinated by the piston design, with the ridges and the thin top ring land. Detonation is a big problem with these engines. Have you (Takhli) built many L series engines or are you breaking new ground here? Just curious.

This issue? You tested the relay?

Just curious about who picked the parts and how they decided. What the goal is. Sounds like you're using the basic "How To Rebuild" and "How To Modify" recommendations. Looks like fun. Good luck.

The "wait a minute and it restarts" is typical of bad ignition module. I notice that you didn't say "new" about the distributor. If everything works correctly except that the engine won't restart right away, that's a sign of the module overheating.

What would be the point of that?

He said that he swapped to a ZX distributor, back in #20. Hard to tell what's happening.

#1 - don't think in terms of "ripping". Check the main circuits in the EFI system. The connections by the battery, both positive (fusible links) and negative sides. Check the the fusible link connections under the two white covers also. Is it behaving the same way as ther last time it was dying or is it different now? Before you said the tach needle was rising and falling and acting weird. Now you say it drops like a rock. Could be your new distributor. Can't remember if you said it was new or used. Considering all of the other odd electrical problems with the blower motor and alternator, it's hard to make a good guess. If you notice any other details besides the engine dying and the tach dropping they would be clues.

Actually, that's not the opposite. Anyway, the wheel just sits on top of the column. The signals and everything else are below it. The horn pad is mounted to the wheel. It'll work. The only electrical contact is a round contact on the bottom of the wheel. A little copper spring-loaded contact slides on it as the wheel turns. Stole this picture from here - http://jdm-car-parts.com/products/datsun-competition-steering-wheel-with-datsun-horn-pad-for-datsun-240z-260z-280z-510-skyline-and-more

Well, that's a bummer. I have an Airtex E8312 pump and a modified Bosch FPR and my pressure typically drops to ~25 psi then just sits there. I've popped fuel lines on old 280Z's and ZX's that had obviously sat for a long time and found good pressure. Clamp the lines individually and you'll know which end has the problem. On starting difficulty in cold weather - I've found that if I crank the engine for about 5 or 6 turns then wait about 20 seconds for the fuel to vaporize the engine starts up much more easily. If I try to get it to go by letting it crank away it seems like just a waste of battery and starter life. I removed my CSV years ago, so it's all injector supply.

If you get on to the MSA site and search "steering wheels" you'll find that they sell a bunch that fit 70-83 model years. Odds are in your favor.

Maybe he's a member and saw the post. It said $400 the first time, and mentioned the transmission. Not so much of a deal now. Never mind.

A hair or piece of rubber maybe got blown through the FPR. I had one that would drop pressure occasionally. You should put that 5 speed in. See if you saved it.

Can't tell if you're asking if the 240Z horn pad will work on a 280Z wheel or if the 240Z wheel will work on a 280Z. Ambiguous. These links might give some clues. http://www.carpartsmanual.com/datsun/Z-1969-1978/steering/steering-wheel Looks like the column (and the nut, other link) never changed so the wheel should seat on the shaft end. So the wheel should work as a whole with the horn pad, I'd guess. http://www.carpartsmanual.com/datsun/Z-1969-1978/steering/steering-column

Not uncommon for the FPR to have an iffy seat, that doesn't always seal. It's just a metal tube pressed against a flat piece of metal. And the check valve in the pump is just a ball and seat design. Both are are all metal, no rubber, so any small piece of debris can hold them open. The injector seats are the same, so a tiny piece of grit can cause problems. Seems like you might just be bored and creating problems for yourself. [Zing!] It happens The spray patterns for the 280Z injectors are typically just a narrow stream. No real pattern. Primitive.

WA CL - Gig Harbor is just west of Tacoma. http://seattle.craigslist.org/kit/pts/5896573380.html

Found the earliest reference in the Z manuals from 1973. Looks like the very early version of the BCDD maybe, with a speed-activated throttle opener. Can't find it described in the chapters, though it might be there. Images from Body Electrical. 1972 compared to 1973. The GB wire at the speedo is the actuator for the relay. And people think that carbs are simpler than EFI.... To the OP - that doesn't seem to be a 1971 speedo. And with no throttle opener solenoid you don't need to worry about the "box" on it.

I've used ceramic muffler repair compound to seal an EGR supply hole (I think that's one you're looking at), after I forced a bolt in to the hole. You can make a bolt in to a self-thread-cutting bolt by grinding a notch into the threads. The exhaust manifold gets very hot further down where it's not cooled by the head, I'm not sure that JB Weld would last long there. Take the old MC off and measure how deep the socket is for the rod from the booster. It needs to be the same distance so that the booster rod will work correctly. But if you get another booster you might have to do some more measuring. If the booster's not already shot it probably won't last long. Consider preventive replacement. I have an Autozone Duralast insulator/mount and it seemed of decent quality and fit and works fine.

That works too. Nissan didn't do a great job though on the internal baffles of the 280Z tanks though. They're known for fuel starvation on sweeping left hand turns when down to about 1/3 tank. I'm only aware because I've experienced the sudden loss of power with my 76 and did some study on it. Never did install a surge tank, I just drive according to the fuel gauge.

Found a pretty good page, it's even Datsun-oriented. Also shows how to use a surge tank for both problems, re SteveJ's other post/suggestion (I didn't see the connection but do now). http://www.superstreetonline.com/how-to/engine/ssts-1119-building-a-fuel-surge-tank/

People often report back pressure from the smaller 240Z return line, making it impossible to control fuel pressure. Too high. They either run new lines or replumb and repurpose a vent line. Apparently they're bigger. Of course, many people also use a super-duper race pump that has way more flow volume than they need. Reasonable specs on the pump for the application and a quick test should answer questions. SteveJ mentioned the other issue in a recent post - internal baffles in the tank to be sure the pump doesn't run dry. A surge tank will help that problem.

Just wanted to mention it since you said you have a fairly big leak. I'm pretty sure that I replaced the crankshaft seal on the engine currently in my car, and I'm getting a few drops for every week it sits in the garage. I won't know if it was my seal repair or something else until I take it apart again. It was fine for quite a while then I jinx'ed myself by saying I had a leak-free engine.

You're considering several different categories of car. The 240Z is the basic, no frills, carb'ed "pure" sports car that Nissan intended. A 280Z is essentially a refined 240Z, with EFI and its associated blandness. A 300ZX is more like a modern car, smooth, quiet, even more bland. The Porsches are a different kind of car, more "engineered" than the Z's, which tend to take the simple route to accomplish an objective. These are all "old" cars though, compared to the computer-controlled vehicles today. You're going to have to learn on the fly to keep any of them running well, unless you find a shop nearby that can work on one. You might consider that in your choice. Find a shop that can help, then choose a car that fits the shop. Or pick the car you want and learn how to make it work. Some of the ideas you're throwing out are a bit exotic and knowledge-intensive, like the RB26 or the twin turbo 300ZX. Even a carb'ed 240Z takes some learning.

Do you have target specs? Like CR, cam lift, duration, etc. Just curious. With that dome it seems like you'd be running high CR and with the valve cutouts, high lift and duration. It's definitely not a factory spec. 8.8 CR engine, I'd guess. Curious. The specs. make the power. It's an odd looking piston shape, but not clear what it's supposed to be doing.

Check the mating surface on the crankshaft for wear. I have an old 240Z propeller shaft with a groove worn in it from a bad seal that didn't get replaced. The metal spring inside can actually break through and contact the sealing surface if it gets bad enough.

Do the number font styles match the other gauges? That might tell you if it's a 1971 gauge. Many emissions devices have a speed detector attached to the speedometer. You might read the various Emission Control chapters to see, or look at wiring diagrams.