Zed Head

Found this in my 1976 FSM. Weirdly, it doesn't show L28 as an application. But it does imply the bolts are 1/4", non-metric, also weird.

Your car is an impulse buy. Candy red sports car. It's not the sensible buy of someone who has planned ahead, with any of CO's criteria. Put it somewhere visible with a big For Sale sign and a link to the CL ad as contact info.

I bought a motorcycle because it caught it my eye, For Sale, in someone's front yard as I drove home from work. Had to have it. Wasn't even looking for one.

9/76 is before 1979.

It was known that he was moving. Google says closed permanently but I think he's still out there. Probably have to call. His fancy new web site is still awaiting its own birth. http://www.zspecialties.com/ https://www.datsunstore.com/

Resto-mod cars really have brought some good money on BAT. I think if you found a grill and some bumpers that would add a lot of value. No offense, but it looks incomplete as it is. Maybe even just a front bumper. Here's a BAT 280Z up for sale. https://bringatrailer.com/listing/1978-datsun-280z-40/

The tow hooks and exposed grill probably aren't going to help. Specs on the engine build would help, if you did it or a pro. A professionally built engine could add value. Home built, maybe not. More details are always good. "Treated" doesn't really mean anything. "Bigger" brakes either. No interior pictures. You forgot to mention the rear strut tower brace, if that's what the red bars in the back window are. Just stuff that pops in to mind. Bringatrailer seems to bring some good prices.

Take off the headgasket and see what shape the stub is in. I did almost exactly what gwri8 described on my one broken bolt. The problem with letting a shop do it is that they sometimes charge by the hour. And it can take a while to get them out. I'd clean up the interface and see if any rust breaker can get in there. The shots with a hammer help break up the bond. I didn't tap mine I gave it some good hard knocks. It came out eventually. But I had more to work with.

Do you have the 3.9 R180? I've never been clear on what ratios the 240's come with. The early 240 4 speeds were 3.592 first gear. 3.592 x 3.9 = 14.00.

Good luck. You can spend a lot of money just on the rebuild. Check that head for warpage. It might need machining, which will add cost. A big shave will need camtower shims. All kinds of nickel and dime stuff. Your new camshaft will need a set of rocker arms and lash pads. I'd put a list together and see where you can save.

What is the ratio of first gear in the transmission, and the differential? A factory stock 1976 280Z has a 3.321 first gear ratio and a 3.54 differential ratio. This gives an 11.76 overall ratio in first gear. A 1981 280ZX has a 3.062 first and 3.9 rear - 11.94 overall. Those ratios will determine how much "pickup" you'll have in first gear. Tire size is important also but the gear ratios are more important. You will achieve more response by increasing either of those two numbers, first gear or the differential ratio.

Where did that "Page 11" come from? Might be some clues there. Never heard of the V-3 program myself, but I have a 280Z. A wiring schematic would show the function of the relays and with that the wiring would be easier. Also, you posted in Fuel Injection instead of a carb forum. No biggy, just not a great intro. Who are you anyway?

That seems to be the difficulty. There are a few guys on the forum who have rebuilt theirs and know where the good parts are. Some of the "kits" apparently are not of high quality. Most say to use Nissan synchros, even though they can be expensive. The bearings are common, it's the synchros that are hard to find, I think.

That seems to be the assumption that is made, based on appearance. But there is no data to back it up. The big rectangular exit hole of the N42 head looks better compared to the N47 hole. Bigger is assumed better. But...no proof. And Nissan's specs are exactly the same. Just adding some info for wil849's search. Lots of ways to spend money with no significant benefit. And possibly make power costing mistakes, like putting round headers on square exhaust ports.

That's bad research. They are identical except for the exhaust port liners.

Don't forget that the switch is normally closed. It opens with oil pressure. That's the flaw in it, if you unplug the oil pressure switch the fuel pump runs with the key On. You'll need another relay to make it act as a safety switch. That diagram hurts my head...

You're going to swap a similar head on to an existing short-block, and install a high-performance cam shaft. So far. You could just install the cam shaft and save the head swap money.

Of course.

Two prongs is correct. One prong is the pressure sensor and the other is the switch. Maybe you picked the wrong prong? Bottom of the T is the switch.

The engine has a head on it. Looks like either an N47 or a P79. Are you sure that's not a 280ZX engine? If it's an N47 head there's no real benefit to swapping to an N42 head. It's been very well described all over the Z sites about where the ID numbers are for the engines and heads. Get those numbers and you'll be way ahead.

Better top off the battery. It's low.

I don't think you mentioned the whine before. Might be that the whine and the vibration and the 4th gear synchro problem are related. Maybe a bad bearing.

Factory 280Z engines had 8.3 CR.

Not enough info. Many piston-combustion chamber combinations.

Redline MT90 has a dramatic effect on worn Nissan synchros. It's not hype, it really works. I had a 3rd gear grind on a 78 5 speed and Redline made it go away, over Valvoline 80W-90 gear oil. It's a cheap fix attempt. Pennzoil Synchromesh has a good reputation also.