Daeron

Be well and thank you!

Pete: The circle you are seeing is just a difference in shading of carbon; if you go check out the Head Differences sticky thread, someone pointed out the same thing about an E31 or some other closed-chamber head there.. (it may have even been me, I can't recall) but it was just a photographic illusion.

Sounds almost like they might have been reading off a list of improvements made on the next generation, but then attributed them to upcoming final 280ZX models. gotta love the boys in Marketing....

Thanks Tony... We had a heat soak issue with my brother's ITS car last weekend, and probably have it solved with a sheetmetal heatshield (already had that) combined with two layers of aluminized sticky expensive insulation material my brother bought at the track. However, as you said, "keep the heat where it belongs, out of the engine bay......"

http://forums.hybridz.org/showthread.php?t=135748&highlight=efi+bible+step

If you are investigating a junkyard/used engine for how good it might be, a compression test is not the way to go. It will do, and it is easy, but ideally you should run a leakdown test. Regardless how low the number is, if all six cylinders are pushing 85-90 PSI the engine will run fairly well, and surprise you with how much power it will have. If the same engine is rebuilt, run in, and re-tested to find 160 psi in all cylinders, it would not be a surprise. If, then, that engine somehow had one cylinder go to 130 while the rest were at 160, it would run like crap. If it ran. Compression checking has almost nothing to do with the absolute number; all that matters is the six cylinders show up within 10 percent of each other.

And, in case the original poster was unaware, an L20B is a four cylinder, 2 liter L-series motor.

Except, the stock engine management cannot take advantage of: A: the "hot" cam B: the (unknown to the computer) increase of air from the ported head and "bigger" intake C: the (equally unknown to the computer) increase of fuel from your pressure regulator or D: the altered breathing characteristics (I believe the technical term is "pumping efficiency" or "volumetric efficiency" caused by changing the stroke, pistons, cam, etc. Take a stock L28E. Throw megasquirt, MAYBE some turbo injectors (actually, simply more modern injectors flowing about what the turbo injectors did.. stock was just under 200, turbo was just over. 250 would be ample, 400 would be fine if you are thinking of having more room for power in the future) and a good cam on the thing, and then PROPERLY TUNE IT on a dyno, and you can likely get her up to around 170-190 wheel horsepower. Or, you could put a cam into a stroker with a huge throttle body and 60 PSI of fuel pressure, and run it on the stock AFM fuel management, and get the same power for alot more money.

New.... or "Remanufactured" by the lowest bidder in a sweatshop factory that replaces failed components and forgets to check anything else for impending failure? Go buy brushes and bearings and rebuild your own starters and alternators. Save 50 bucks, keep junk out of junkyards and know it is done right. To the OP: It is probably your fuel pump relay that is the problem. Many of us have discovered that previous owners bypassed the fuel pump relay entirely and custom wired the fuel pump with a switched, fused 12V line. This is NOT a good idea. http://forums.hybridz.org/showthread.php?t=135748&highlight=efi+bible+step That should help you in your diagnosis.

Haven't done any intake/exhaust work myself since getting them, but I must say, GearWrenches are worth their weight in GOLD!!

If I am not mistake, there was an "early E88 head" which had chambers all but identical to the E31 heads; peanut shaped, just like what we see here. I do not know if I have ever seen one of these personally, and this head looks like it has probably been worked over even if it IS this "early E88" because the chamber side of those valve seats just doesn't look factory (ie the valve shrouding) and it also looks like there might be an awkward ridge to provide a hot-spot for unwanted ignition. I would definitely consider re-ringing, re-honing, and having a 3 angle valve job done on the head if this is a GT2 motor. Just out of curiosity, what do the ports look like on this head? It certainly looks like a nice motor you bought.

I'm certainly no Z32 aficionado or egg-head, but I know the SBC swap is about six pains in the ass into this car. It is totally doable, but you talk about knuckle-dragger approach, and I know nothing different between SBC and SBF that would simplify the swap. Granted, I don;t know much about domestic Iron, but I know enough to know that the modular OHC Ford V8 is a very different critter from the 302 and that the 302 is the better match (dimensionally) for the SBC. If you want a quick and easy V8 swap, you need a car built from 1970 to 1983... Either S30 (240, 260, 280Z) or S130 (280ZX) If you want to swap a V8 into a 300ZX, then you can certainly do it, but it isn't going to be "knuckle-dragger" unless the V8 is around 3 liters.

This advice can apply to any job, and every shade tree mechanic has his own threshold of "job complexity" where labeling like this becomes necessary.... ...so, once in a while I like to throw out the idea of color coding. the first time I had to do a head job on my own car I grabbed some labels I had (they were for a form feed dot matrix printer, obsolete stationary) and an 8 color Sharpie set. Color coding that stuff kept me from having to identify any of it specifically.. it became "thing" and "to thing" on vacuum hoses, etc. An eight color sharpie set makes color coding easy. Color coding makes lots of things easy. Do you need things boiled down that simple for you? Maybe not, but every simplification makes the job go quicker AND easier. When you need to use crutches, you want to have good crutches around.

Thanks, man! (or mate.. thats what I wanna call you but I hate to sound like a pedantic american so I use my own lingo) by the way, oz, what is your proper name? Mine's shawn, and you;ve probly told me yours already but I can't remember it. I'm having (if you can't tell) a foggy, AND beer-laden evening and I'm feeling lazy. I didn't even click through on my own links, I just went on my recollections of what you asked and what I posted. Even still, I like to think I'm useful in recycling this kinda stuff. (by the way by beer-laden, I mean I drink good beer. Michelob Amber Bock is my standard, but as a rule I mix things up, and never drink a beer unless it is noticably darker in color than my own Irish skin. So don't think i'm swilling down cans of American swine over here either. Burp.)

No, honestly, I do not personally have any. Thats why I said my bit about regurgitating information above to be honest. However, within the last ahhh, two or three weeks, I know I pointed ozconnection towards a few posts brian (1 fast z) had made regarding the topic that I usually take as holy writ until I see otherwise. Let me see if I can find that thread.. EDIT here is my reply: I also want to add that I had envisioned a very shallow valve recess in these pistons; One would not, by any means, NEED to bore this bowl out that deep. Unless I am mistaken, in one of the two threads linked was mention of how thin you can and cannot get away with. At the very least, the post should be useful as a litmus test for you regarding these pistons. the other one has nothing to do with piston machining, and only piston-to-head clearance. Two valuable threads to keep up the sleeve IMHO though.

Well, I have to ask (since we stumbled on a box of like, either 7 or 9 of the aluminum adapters a few months ago) What about putting twin DGV webers on in place of the SU's? My Dad forced me to shut my mouth and quit whining about four barrels on Z-cars a long time ago; it goes against my natural grain but I grudgingly admit power can be made and any complaints I may have are, in the face of a well built engine all around it, superfluous. Despite that, I *still* feel that 1 and 6 get the short end of the stick with just about any 4 barrel manifold I have seen, and the twin Weber downdraft seems to me the best of both worlds (except for the fact that you have two carbs instead of one.) Obviously the big, heat absorbing J that the adapter makes is a drawback.. but I know many people have used them as "big power" SU replacements on many cars equipped with SUs. why not throw them on instead of a holley?

Excellent! I just had to point it out; its part of my nature. One rule my family and I learned this weekend: no such thing as too many layers of heat shielding!! (long, mostly irrelevant story, heh)

I'm not understanding this quite clearly. The valves and spark plug are on one side of the combustion chamber, and the quench pad of the combustion chamber (and the intake/exhaust) is on the other side. Correspondingly, on the piston, one side has valve reliefs, and the other side you want to keep flat and push it up against the quench pad as close as possible. So, a thin head gasket allows the flat top of the intake/exhaust side of the piston up close to the flat quench pad of the head. You ask about the "non-quench side of the head" and it appears to mean you are actually referencing removing material from the piston, on the non-quench side. That would be the side where your valve reliefs are. The way to relieve compression (since you're running an ultra-thin gasket) is to carve out a recess in the piston, with the bottom equal to the deepest section of the valve relief. Extend this bowl as far towards the inlet/exhaust side as the combustion chamber is in the cylinder head. Shape it similarly, but smaller (if anything) than the outline of the "peanut" combustion chamber. I'm just regurgitating information; but it is good information nevertheless. Take it, go play games with the calculator, and figure out: -what rods you're using -what compression you want. Input the data and determine: -how close you want to get to the head -how thin you want the gasket and find out what volume your recess needs to be. My logic is, if you stick with the thinnest spot Nissan produced the pistons with, then you are likely safe. Hope this helps.

Cool! This is a great build thread, I can't believe I missed it this long. I, too, love seeing people (like me) pour ridiculous amounts of time cleaning and repainting all the stuff that is totally hidden.

http://forums.hybridz.org/showthread.php?t=135748&highlight=efi+bible+step http://www.atlanticz.ca/zclub/techtips/electrical.htm

The aluminum wire cover could function more as a cooker for the wire harness unless used in tandem with some other barrier to keep the heat from the header away from the aluminum cover itself. The radiant heat that would otherwise go straight into your harness and cause an issue, will instead rapidly heat the aluminum wire cover and while some of it will be kept out, if you are THAT close, you'll just wind up cooking the whole affair together. I mean, the cover would probably be more help than harm, but I am pointing out that it's like shooting your foot with a .22 rather than a .45, unless there's another heat shield. The wire cover WOULD let you get away with a rinky-dink heat shield, though, while tucking the harness away at the same time.

Well, you can go with an ITB setup. The car has 40mm webers on it now, so just a set of throttles and the hardware it would take to run it would run you around $1000. The L-6 came with EFI from the factory for about ten years, though. And in addition to that, people have retrofitted (with some effort) the EFI electronics system from later Nissans (as well as other cars) onto L24/6/8s with stock and aftermarket EFI hardware on them. The simplest and easiest and cheapest way to convert to EFI would be to find someone with a 75-78 280Z or 79-83 280ZX parts car or car with a blown motor, and take the complete intake tract, and the engine sub-harness and computer, along with all the sensors and the fuel pump, and install them onto your car. Depending on the year of the car and the way the fuel delivery system is currently set up, you may need to do some work with fuel lines. If the car was made with EFI from the factory the lines would be adequate, so long as they are still stock, but if it was originally a carb'd car you would likely need to do a little work there. That would be the most difficult and most exzpensive single part of this conversion, if you go this route. If you get a stock EFI manifold, you could theoretically go to the junkyard and get a suitable TB with a TPS, find a nice looking MAP, get a good modern CTS and a few other sensors and switches. Then you could pick up a MegaSquirt system (that is a cheap, do-it-yourself standalone EFI computer. You can buy it assembled, or you could buy the board and the components and solder it all together yourself to save money.) and some relays and other associated wiring and be going to the races. Honestly, if you are willing to go using junkyard stuff to extreme, you could probably find a nice, modern 6 cylinder car to take a wiring harness from to use for your project. (shoot, that isn't a bad idea.....)

I didn't want to sound rude, but I was REALLY tempted to post this before, and since someone replied without noting how old this thread is and how random the bump is... *I* have always said you've got no business forum-chatting if you can't recognize necroposting