NewZed

The water temperature SWITCH only matters when the water temperature is low. It completes the circuit for the ignition module to use the other pickup coil in the distributor, to advance the timing ~6 degrees. Not exactly clear why, but maybe for a faster idle while the engine is cold. It has no effect once the engine is warm. The water temperature sensor, the one with the same Bosch style connector as the injectors, affects how the EFI works all the time. The higher the resistance across the two wires, the richer the EFI runs. It's common for corrosion in the connection to cause rich running. The Engine Fuel section in the FSM has a great explanation of what most of the components are for and how they work, with pictures and test procedures for most of them.

Ignition switch wire switched with combo switch wire, at steering column? Turn on combo switch, send power to ignition system? The wiring diagram in the FSM, body Electrical section, has the wire colors listed. Easy to check.

For blocking the cold start valve line - http://www.mcmaster.com/#5272k147/=f26fza Not pretty, but it is effective.

Do you mean integral to the strut insert? "Cart" makes no sense. Are you sure the gland nut isn't just stuck to the top of the insert? Another picture, pulled back to show more of the insert would be interesting. Just doing some grammar policing...

There's a picture in the FSM.

rejracer, I missed your post, I'm just seeing it. I'll check out the Syncromesh, it sounds interesting. In the meantime I tried a 50/50 blend of Valvoline Dex/Merc ATF and Swepco 201. It made the drop in to gear easier for relaxed driving but I lost a couple hundred RPM on the gear-grind limit when in a hurry, and it was noisier when it happened. I drained the 50/50 blend and re-mixed the Swepco 201 I had taken out, to give a 25% ATF blend. That made a significant difference and it feels like the best it's been, about the same as the 100% Swepco. I think that 50/50 was just too thin for the worn parts. I ordered some parts, inserts and springs, from Courtesy Nissan and will probably just use what I have before opening the transmission to see what I can improve, unless GM's Syncromesh sounds amazing. Thanks for the tip.

I thought that one of the first things you are supposed to do with Megasquirt is get the Megasquirt timing readout to match the timing light, by adjusting the trigger offset. Once you get that it doesn't matter if your distributor is 180 off or not, since Megasquirt controls the timing. Sounds like you've started in the middle of the Megasquirt setup process. http://www.megamanual.com/ms2/tune.htm#spark

Pretty good road-side problem-solving. You need good steady fuel flow and fuel pressure for EFI to work right. If you went from no-flow to full-flow by blowing air back though the filter, damper, pump and tank, then everything fromthere back to the tank should be your first area of concentration. You could be running at low pressure even with good flow. I wouldn't do much more past the fuel filter except put a pressure gauge on and do some work to make sure that you can maintain fuel pressure. Don't worry about the injectors or their connectors until you're getting the right pressure to them.

Disconnect everything from the switch to the starter and measure resistance to ground from every pin in the various connectors with an ohm-meter. If you find the pin or connection with zero resistance, then you'll know that anything connected to that pin should be looked at (unless the pin is supposed to be to ground, of course - have the wiring diagram handy). Then you can focus on the path that that one pin uses instead of worrying about everything from the battery to the starter, plus any branches. It really doesn't take much time, and when you find the connection that is grounded, but shouldn't be, you'll know you're on the right "path". It's just a meter-based method, using the wiring diagram, versus the eyeball technique. You'll probably find the problem with a lot less effort than pulling out the entire harness. Of course, tearing things apart is part of the fun.

Sounds like you know what you're doing. You might try leaving the battery disconnected, and the shunt, and the fusible link, turn the key to ACC and check the various connectors for what portion of the circuit the short is in. Isolate it to a smaller area. Check the shunt for an internal short, and short to the housing also. If you're blowing a 40 amp link, it would be a low resistance short. That's a lot of current. Something might have melted when the 80 amp link blew before.

Did things work right before the ZX alternator or is this problem coincident with the ZX alternator "upgrade"? Which of the two links blow? When do(es) they(it) blow - when the battery is connected, when the key is turned to On, or when the key is turned to Start? Have you tried disconnecting the shunt and testing each terminal for a short to ground? Test each connector for a direct short to ground also. There's not much to the shunt, it just directs a portion of the charging current through the ammeter. It does have connections to the VR though, so if you just modified the wiring for the ZX alternator, you might have misplaced a wire. I would guess one of the white ones. There's a good 1975 wiring diagram on http://www.atlanticz.ca/zclub/techtips/electrical.htm

You might take a look at the spark plugs. If it's lean everywhere, they should be pretty white. It's the old, pre-AFR gauge way of evaluating mixture. One more piece of data. Might help you with the JWT guy also.

Isn't .040" = 1.01 MM? Thinner than the stock 1.25 mm gasket? Will you be stacking them? I'm not up to speed on whether the 1.25 mm refers to compressed thickness or if the installed thickness is actually thinner, so could be off target. Just curious.

Here is more than Haynes - http://www.xenons30.com/reference.html . Look in the Electrical and the Engine Fuel sections. Small wiring diagrams in each. I would bet good money that the person who modified your wiring looked more like you than Afro American. No need to expose your prejudice or lack of awareness to the world. Just keep it hidden. This a car forum.

from the post before - I was trying to clarify what you were asking. I am interested in what's out there in engine management so anything I can learn about the various companies is valuable to me. But if you could step back and be a little more objective, you would see that you just made my point for me in your last post. Your issue is with the one guy you talked to at JWT, not their products. Just trying to help you focus on the real issue...

Oops, didn't know that Google had its own acronym for its image search function...

Are those before and after pictures? They don't match. One shows what looks like the stock R200 and another shows what looks like a short-nose diff with CVs. Maybe the MM short-nose diff conversion package. That rust looks pretty severe, along with the gouged frame rail (first picture), and the front end damage. It might be worth parts. Compare the cost of the MM parts, and confirm what it has, and if you want the parts. There's probably more rust damage that's not so easily visible. These cars don't have "frames" to straighten, with rails that you can work on, they are unibody or monocoque. Basically a big metal box, with stiffening rails welded on in important areas.

As I had wondered - your post is really a complaint about how you were treated on the telephone, not a technical question. Should probably be in the Non-Tech forum, if allowed at all. Why don't you call back and try to talk to someone else before you trash the whole organization and their products? Maybe you got a bad apple.

Where did you get the dyno work done? Might as well put both parties' names out there, just to make things even. Maybe the dyno shop isn't that good, and the Wolf tech is right?...

Here's a couple of informative threads - http://forums.hybridz.org/index.php/topic/38461-240z-260z-280z-turbo-swap-guide/ http://forums.hybridz.org/index.php/topic/50208-the-ultimate-l28et-guidewhat-you-need-for-350whp/

Everyone up to palmetto's post gave a suggestion. johnc gave a link with good information. Miles even gave the words to put in the search box. ROTW said thank you. You should let him complain if he wants to, it's his thread.

By "maximize timing" I was referring to advancing for maximum power. The typical dyno tune procedure, from my understanding. The knock on high CR has been that knocking occurs before you can advance your timing enough to get maximum power. But some say that they don't have the problem. It would be interesting to ask what their cylinder pressures are when checked with a standard compression tester. Even with the variability in gauges, a trend might show. A true measurement instead of a calculated guess. Again, just looking for something new besides the "I did it, don't know why you can't" response that seems to pop up in every detonation/flat tops with N42/Maxima N47 head conversation. Doing something without understanding how it happened isn't very satisfying.

It's just a perspective that goes beyond "I run flat tops at 10:1 CR and don't have any problems". It's a starting point that gets past just the assembly of parts and gets in to what's happening in the engine. For example, cylinder pressure at TDC should mean more than the mathematically derived CR, calculated from stroke and chamber volume. CR is a vague, fairly meaningless number, as is the term "dynamic CR". The cam numbers and the mathematical CR determine cylinder pressure, along with VE factors. The discussions would be more enlightening if they went along those lines.

Something has always bothered me about the flat top/ high CR/ detonation discussions. If someone can run a high CR and maximized timing, when other people can't, assuming no combustion chamber modification (quench factors), it seems reasonable that it might be because the setup has low volumetric efficiency and/or exhaust gas scavenging. The similar engine that detonates must be packing more active fuel molecules in to the combustion chamber than the other, without the dilution of inert exhaust gases. For example, if I install a Maxima N47 head on a flat-top F54 block and run 38 degrees total timing on 92 octane, and don't get knocking, I should start looking for obstructions in the intake and exhaust systems, or poor cam design. It knocks for other people, why not me? Detonation is just the result, chemistry and physics, of packing a certain quantity, of the right concentration of fuel and oxygen, in to a confined space at a certain temperature and pressure. When pressure, temperature and concentration are all correct, the mixture that that hasn't been burned from the spark initiation blows up, all at once. VE determines how much gets shoved in, which determines cylinder pressure, and the scavenging of exhaust gases determines how diluted the mixture will be. You could say that if you build a high CR L engine and it doesn't detonate on pump gas before you get the timing advance maximized, you must have done something wrong. Just an alternative perspective on an old topic. It should be a point of pride to get a relatively low CR engine to knock, it means your skill at maximizing the active charge in the combustion chamber is high.

You're saying that low HP detonation is different than high HP detonation?