NewZed

Fuel pressure regulators have been known to get stuck/clogged. High pressure = low mileage.

That would be pretty cool to see, just to gain a little more insight in to what works and why. Thanks for taking my post in a positive way, you could have told me to get stuffed and went away. Just to round out the picture a little bit, what type of coil were/are you using and what is its primary circuit resistance? I think that HEI module is designed for a sub-one ohm coil, about 0.4-0.5, from various internet sources. Could be a factor, maybe. The ZX coil is 0.84 - 1.02 according to the FSM. For the record, I'm using an HEI module with a Z31 coil (~one ohm primary, 10K secondary), with a 280Z style single position pickup coil (not the stator ring), and it works great. Another odd thing - the GM HEI stator looks like the ZX style stator, ring-shaped, just eight points instead of six. If you were just eye-balling parts, you'd probably pick the ZX style distributor instead of the 280Z style as the one that would work right. To the OP - if the ZX distributor is in good shape it would probably be the easiest to install. Fewer wires to mess with, just power and coil negative. Then you can measure your advance characteristics while the engine is running, and decide if you need to make any changes. That's another post though.

Here's a failry simple look at noise sources and how to work with them, from a company that's been in the data acquisition business for a while. Might help you figure out you if the noise is in the sensor, the wiring or the sensor location. http://www.omega.com/techref/das/noise.html

Which problem are you trying to fix? The LC-1 not giving the correct readings due to noise (you reprogrammed it for some reason)? Or are you trying to fix the "Settings Configuration Error..." which would be an MS thing. Or the bucking problem, which would be tuning. You've described a lot of simultaneous stuff happening.

From the linked article - "If a reluctor of different design is used, the dwell may end up longer or shorter than the ideal time. The HEI reluctor rotor is comprised of a wheel with short-duration spikes on it. If a rotor is used with long-duration ramps before thespikes, the bias voltage on W may increase too much, creating the aforementioned stumble at higher RPMs" I have a problem sometimes, similar to what you might have done in your post, in projecting what I think might be happening in to what I write. Quite often I have to go back and remove the stuff I don't really know or add a qualifying statement. I copied the the relevant passages from the articel and your post about the reasonthe ZX distributor won't work. A reference about the AC signal produced by the Zx type distributor would fill in a missing piece. I've seen that article before and noticed that the two motorcyle igntion systems described and their behavior using the HEI module don't seem to match anything I've seen described using the Z type distributor. Interesting conversation. A few words or references supporting the comments about the ZX style reluctor waveform behavior, and also the "unstable" behavior that you saw using it (what do you mean by "stable" and how does it relate to the article - coil stuck on, cross-talk, or whatever) would add a lot. I'd like to know, I have a spare ZX distributor in the garage. Edit - Ideally, we'd have something like the traces on this web page - http://jaguar.professional.org/ignition/ to work with to answer some questions. Wish i had an oscilloscope.

Be careful about making decsions based on just one comment. Read all that you can find and make up your own mind. Most of what Zark has written goes against what you'll find about how the GM HEI module works and how it performs. He's interpreting motorcycle "knowledge" from one internet thread and applying it to ZX distributors. Needing a hotter plug for electronic ignition, over points, doesn't really make sense. Plug temperature choice has more to do with the combustion process and carbon buildup over time, not spark initiation. In general, Post #6 makes little sense. He might have had a real problem with the ZX distributor and the HEI module, but the reasoning behind why doesn't fit generally accepted knowledge. Your biggest concern for engine performance should be the advance curves, vacuum and centrifugal. For durabilty, the condition of the distributors. Have you taken them apart yet? Tested the pickup coils' resistance? Odds are pretty good that one is broken and the choice will be made for you.

I looked but couldn't find a reference, in a drawing or in the list at the back of the chapter. I think that Nissan assumed that they would never be removed, indicated by their inspection recomendation that says if wear is found in the bearing surface, "replace cylinder head assembly".

Burned by the Page 94 typo? "How to Rebuild..."?

Your exhaust sounds very loud considering it's going through a turbine. Is there any exhaust pipe at all after the turbo? The backfiring reminds me of what a couple of V8s I've had in the past sounded like when they had a flattened cam lobe. You said that it ran for a month. Did it run well? And is the problem exactly the same as before? Has it always backfired like that? You should summarize the last month or two to give a better picture. It doesn't sound good right now, seems like bigger problems than just won't stay running.

Core.

Did you check the parting surface between the head and block? Look for coolant residue or surface rust. I had an N42/N42 engine that leaked at the spot right above the starter, between the head and block. I don't know if the head was warped or the head gasket just gave out after many miles. It only leaked during warmup and cool down, when the engine was at full operating temperature it sealed itself up.

Start an anonymous poll thread. Should Ben use the 77 cam or the P90 cam? That way no one gets the blame if it fails later. You could also call Isky and ask about the cracked dowel pin hole. They might tell you not to worry about the crack and it will be a no-brainer.

Never mind. Happy holidays.

You could go super way back old school and use paper - ARIZONA Z CAR 2043 East Quartz St. Mesa, AZ 85213 Just an option. You could write him a letter and ask him to check his e-mail.

The first thing I would focus on is the wiring hacks at your fusible links terminal (last picture, with the wire nut). Looks like someone used plain old wire for one, and completely removed a whole link block. You'll have to look at the Air Conditioning chapter of the FSM to figure out your small vacuum hose connections. There should be a connection under the throttle body for the BCDD. Look in the Emissions chapter for a drawing. The Electrical chapter will show you where some of the various wires should be connected. The diagrams have color codes for each wire. White with black stripe is switched power, be careful with it especially considering your lack of fusible links. The blue wire iwth female bullet probably goes to what you're calling the proportioning valve. It's actually the brake pressure differential switch. It activates the brake light in the tach (or speedometer, wherever it is) if there's an imbalance. Described in Electrical chapter. One of the blue wires probably goes from your coil (-) to the ECU Pin #1 so the old ECU could "know" when to squirt the injectors. Engine Fuel chapter. Charcoal canister stuff is in the Emissions chapter also. The wiring diagram would help you. Here's a link to one, can't verify accuracy - http://www.atlanticz.ca/zclub/techtips/wiringdiagrams/F77ZCAR-WIRING1.pdf

Pretty sure that the one on the lower left is the thermotime switch, lower right it is the coolant temperature sensor, upper right is the EGR switch or the top gear vacuum advance switch, upper left is gauge sender. Looking at the picture, not position on the car. There's actually a drawing somehwere in the FSM that shows and labels all of them.

I was just trying to get some details. Couldn't tell how familiar you were with how things are supposed to work. You do know that there should be a few threads showing when the gland nut is tight? "The gland nut will not close..." I assume this means that you can't get the threads started? And, maybe finally, are you using the Tokico gland nut or the old one that you took off? Even if you have the Tokico nut, it might be the wrong one per John C's comments above. They've been known to put the wrong nuts in the package. It could just be the wrong gland nut. Lay your old shock/insert next to the new one and compare lengths.

One last thing. Since your thread is void of any specific measurements or pictures, and vague in general, it's reasonable to guess that you might not be aware that the spacer that comes with the shock is a press fit on the bottom of the shock. About two millimeters of engagement. If you're just dropping the spacer in the hole then dropping the shock on top of it, the spacer won't be centered and it won't be properly pressed on to the shock. This would explain why the right parts aren't working for you. Good luck.

I get the feeling that he's going to trim the spacer down until the gland nut tightens on the strut tube. So it looks right. I hope I'm wrong, and end up looking like an ass.

How far? And when you say they stick out, do you mean that the gland nut won't screw down all the way? Or have you even tried putting the gland nut on? Please don't ask what a gland nut is.

I would take a breather, study what's been suggested, and put a sensible plan together. I have this vision of you throwing everything together, getting it running, then revving the crap out of it until it blows up just to vent some frustration. Seriously, you have several paths to get a good cam in the engine and get things working. The whole cam, cam tower and rocker arm things have been discussed to death on the various forums. The most recommended suggestion seems to be to take the cam, towers and rocker arms out as a complete assembly, with every part in the same order and orientation and swap them over to the other head. Tap on the cam towers as you slowly tghten the bolts to make sure the cam spins freely befoe you torque the bolts down. "Blue" up all of the rubbing parts afterward, spin the engine over a few times, then check for high spots and/or odd wear patterns. This is what I've learned. I've never had a cam off though.

It's in the FAQs but easy to miss because it's in the "L Series" box at the top of the Powertrain page. Lots of other good stuff on the L series page. Here's a link to BRAAP's tips - http://forums.hybridz.org/index.php/topic/95316-braaps-l6-efi-induction-advice-and-tips/

Just re-read your thread and see that you don't mention fuel pressure. Are you assuming that something's happening based on the pump noise, or the volume of fuel that you see coming out of the rail's return line? To know for sure, you should measure fuel pressure, and collect and measure the fuel that comes out in a known amount of time. It might not be "losing its prime" at all, maybe it's just a weak pump. Or it might be fine except for the noise. You need the numbers.

Maybe you just have a blockage between the pump and the rail's outlet. Have you tried disconnecting the line at various spots to see if the pump will pump at all? Also, I couldn't tell from your pictures, but you might have the fuel lines connected backwards, or the wiring. The pump will spin in reverse if the electrical connections are backward. It happens.

The dowel pin might be just for location. Clamping force from the bolt would hold the sprocket. The crack might be irrelavant since it's "pinned" by the dowel hole. Just a proposal worth thinking about. Edit - I got curious, did a search and found an old Hybridz thread on the same topic - http://forums.hybrid...-issues-beware/ And another - http://www.the510realm.com/viewtopic.php?f=2&t=11001&view=next