Kingman

VG30 fuel injectors in general have a high failure rate, Pathfinders, Hardbodies, 300ZXs, 200ZXSEs, etc. While the engine is running, try unplugging one injector at a time. The one that makes no difference would be the dead injector.

Yeah, the sensors can cause some serious trouble, especially on 300ZXs (known as the Cylinder Head Temperature Sensor by the Z crowd) and MPFI Pathfinders. They seem to be a bit more reactive to the failing sensors than our (oops, your) TBI is. Glad to hear it's running better. I keep forgetting to make some serious ground cables for mine, I've got way too much wiring laying around. Also, sometimes a significantly better ground with advance your timing a little so it might be worth it to double check that once you do it.

I would keep the Hardbody H4 lights, instead of the Pathfinder 9004s. There is infinitely more choices for some seriously powerful lighting set ups with H4s and a hefty relayed wiring harness. 135W low and 160W high is what I have in my Datsun 620 pickup, they are like a new sun lighting up the night. CieBie lenses are a European code spec, so you can run the insane amounts of power without blinding oncoming traffic.

Up until 150F, the computer runs the engine in open-loop mode with no inputs from any sensor, just a pre-set mapped ratio. After that is when closed-loop is activated and the computer takes constant readings from the various sensors, O2 sensor being one of them.

I'm 99.999999999% positive I fried the Z computer. I rewired the injectors to match what the Z car ran, didn't help. Fuel pump quit coming on and priming like it should with the computer also, but when I plug the TBI computer in it primes like it should. The fuel system was working fine. There's also no more spark when cranking, only a spark when the ignition switch is turned to OFF.

I've always had the habit of gapping new plugs, I usually seem to get at least one or two that aren't anywhere near spec.

Thanks! A little bit of what I've done is sort of "for now" because I don't have a ton of money to buy all the parts I'd like to. It was painstaking taking the time to perfectly measure every wire feed, solder the connections, vinyl glue and shrink wrap them, then follow the wires with electrical tape and finally guttering. All of the wires I've ran are that way, at least I'll know there won't be any reliability issues with that part. You are correct, the intake will hit the lip above the firewall. There's 1/4" of room above, under mild bumps and acceleration it shouldn't twist quite that bad but under full torque load or huge bumps it will, guaranteed. I need to rework it a little, but once the motor is running. I haven't figured out the air intake routing. I'm going to just run some 3" flexible tubing straight off the throttle body, MAF next to that, and then bend it to where I want the air box mounted. The stock pieces I have simply won't allow for what I want. I have it set up now with no filter attached just for a test start and revving. To road test it I'll then need to run a secure intake. The sequential fire VS batch-fire is a strange debate. Theoretically it should give better performance and economy, but it doesn't. Real world numbers have shown tons of times that the only net increase in economy and efficiency is at or a little bit above idle. Less atomization of fuel when sprayed into a closed valve. Above a low point, there's virtually no difference and at best 1MPG increase. However to run a turbo... sequential fire is desirable... I also didn't like how the fuel lines were unevenly spaced on their way up to the fuel rail, so I made some holder things with zip ties. Zip ties hold the world together!

It is. Eventually I will run a '87+ ECU where it will actually run full sequential and not burn up the load transistors.

Yet more garbage from Consumer Reports. Fram filters use a weak filter element and a cardboard cap known to deteriorate quickly. They are a terrible filter in every respect. Use Nissan (Bosch), Purolator, or WIX (NAPA Gold) for the best filtration and anti-drain back. Thicker oil is used to make up for the greater differences in bearing tolerances that come from age/mileage. The hydraulic lifters also wear out, and have a harder time keeping thinner oil past the o-rings, using thicker oil will help them out with staying pumped up. The viscosity difference in the oils isn't enough to make a noticeable impact on mileage and power output, usually. It also depends on how good your piston rings are, crank case ventilation system, valve seats, etc. for how often the oil needs to be changed. Some engines after only a few thousand miles will have a strong presence of gasoline in the oil, it's good to change it then. I run Chevron brand 10W30. Chevron is the most highly detergent and cleaning oils out on the market.

Everything is on, I tried starting it and it was a no-go. Just straight cranking. I'm glad it didn't start, I learned the ECUs don't take kindly to: A) Me tapping the wrong wire for an injector, that on the TBI computer is a ground and on the Z31 computer is a 12V output. Thankfully I didn't fry the computer, that would really piss me off. Batch-fire injectors being ran through only two switched circuits instead of 6 to carry the load. I thought I could cheat and run only 2 pins from the ECU to the injectors since mine was retrofitted at the dealer for a campaign they had. The newer computers run full sequential, the older ones were retrofitted to batch-fire since they were blowing computers left and right. So I have to run the 6 wires from the computer and splice them into the 2 feed lines for the injectors, not a big deal at all. Fix that tomorrow and hopefully it'll run. I'm not too hopeful though...

X2. Some seriously impressive stuff there!

That's pretty crappy man. I've been running straight water in mine since I put the motor in, it's ran dead on at 180F.

I misunderstood the first part then, that would be a good idea for reliability but not really necessary. I did, however, understand what you're saying about the SAS. I know you want to get rid of the R200, I was just pointing out as an example something that most people don't realize - the factory running gear is insanely strong. I can see the need to upgrade the rear axle if you run a lower gear reduction transfer case (factory TX-10 is 2:1) with the 450HP. Sounds like you've done your homework, can't wait to see a build thread!

Sorry for the random thought, but would you please make your sig pic smaller?!

The H223B rear end is damn near equivalent in strength to the Ford 9", it can handle the power. Also, a Dana 60 is EXTREMELY heavy! Ever tried to pick one up? That's a ton of un-sprung weight added to a vehicle not designed for anywhere near that amount. Food for thought on the strength of the stock differentials. Our R200 front differential is the rear differential in the Nissan 300ZXs. These have been proved to handle 600+HP without issue.

I believe the light comes on when the oil pressure is less than 5 PSI.

Hmmm, I just went out and checked mine and they are all perfect... A good heads up!

Why does making a coolant hose that starts at 3/4" ID and opens up to 7/8" ID have to be so farking hard? Couple trips to NAPA to even find a hose that did that, a bunch of cut up metal tubing, and lots of guesswork... here's the disaster now known as my thermostat bypass hose for the heater core. I also ran the fuel injector wiring to the ECU. Wasn't that productive of a day...

The plugs for the factory shocks are down on the frame, right next to the UCAs.

I'm not sure what it is exactly, but it plugs into the wires that run along side the positive battery cable, and the other end routes back up the conduit going to the firewall.

Just an update. Nismopu came down from Woodland to check on my progress, we got the MAF sensor wiring figured out which has been hanging me up for a little while. Turns out I can use the TBI wiring for the Z31 sensor, only difference is the Z31 has a heater element that the Pathfinder doesn't. Makes things easier. Injectors are also easy, pins 101 and 106 at the computer to run all 6 injectors. Yeeeeeeee! It's getting closer, I'm shaving off some all of the emissions stuff and an accessory air regulator...thing (pointless), it makes wiring a lot easier since that thing runs wires through a few other sensors. I also originally had the fuel lines backwards, I was tired... so the stock fuel lines fit perfectly on the new intake. I need to run the whopping THREE wires to the computer for the injectors and then that part will be done, then finally mount the upper plenum, extend the TPS wiring since the TBI wiring is the same but too short, figure out a hose for the upper plenum coolant hose, go get some flexi-tubing for the air intake, and find a way to mount the air box. That about covers it really, there's not much more work to do. Once it's running I'll take it in to an exhaust shop and have them weld in a new bung to mount the Z31 oxygen sensor. So I may be running a while without one, won't hurt anything just have a larger appetite.

All that's needed is putting the transfer case and transmission in neutral, remove the drive shaft is even better.

James, I found the sensor on RockAuto, it's under the cooling category, click on "coolant temperature sensor."

You may be tightening it too tight and the belt can't make the turns, try loosening it a lot and restart, you'd be surprised how loose a belt can be without squealing.

Yes, but the server has only so much capacity.