michaelp

WOW man..WOW..really? You're just digging yourself into a big hole. The typical "TPS" Throttle Position Sensor, is a Potentiometer. It varies voltage throughout its sweep, its a variable resistor called a Potentiometer, utilizing 3 wires. The 3 typical terminals would be VREF (Voltage Reference), GRD (Ground), and SIG/SGN (SIGNAL). The Z31 utilizes a single-connector TPS on manual cars, as throttle position SWITCH, and is only an idle switch. 86-89 Automatic cars have a secondary connector that has a potentiometer to show true throttle position for the transmission control module, while 84-85 are fully mechanical. ALL 86-89 cars have the connector in the engine wiring harness, but it does not do anything on manuals. The Automatic TPS has the secondary set wires on it with the connector, but the manual does not. The automatic TPS can be put on a manual car and it'll function perfectly everytime, you can even plug that connector in...but that connector isnt doing ANYTHING. Source: 1989 300ZX FSM Don't argue with stuff you don't know, and have just observed on your cars. I've made Z31 engine harness', I know where that connector goes, and its for nothing on the manual. If you get a chance to mess with nistune, you'll also notice it shows no throttle position on Z31 ECUs, but it will on Z32s. It shows "IDLESWITCH" as one of the possible faults. http://xenonz31.com/reference.html

Yeah, I already PMed him just curious if anyone else has anything.

I'm looking for a COMPLETE L28ET, and depending on what it is (if it has an upgraded turbo or something) I may be interested in trading a set of Italian-Made triple webers that were installed on my S30 in 1982, but were never driven on (I have new gaskets and seals for them). Other NA stuff I'd be willing to trade are 2 sets of headers (MSA and Pacesetter),Mallory distributor, Pacesetter exhaust, etc...

Because all you've owned were 86+ automatics, no manuals? The automatics had a separate 3-wire plug for a potentiometer, it controlled the transmission and thats all. Doesn't affect the way the engine functions at all, like my 88T which has only the one connector to the TPS and an idle switch...because its a man's car with a 5spd.

NO!. The Z31 does NOT work off 5-volt reference, in-fact you'll have 12-volts at the reference wire to the TPS. ALL the TPS is on the Z31 is an idle switch, and also a WOT switch on automatics (hence the 3 wires). On manual TPS', only 2 of the terminals/wires are actually used. 12-volt reference, and the "signal" wire for the idle switch to the ECU, which when the throttle is closed it has 12v sent to it.

Thing with a broken hose is the cold start idle valve. Runs to the intake on the DS. I removed my EGR by making a custom block-off plate for the plenum side, took 10 minutes. Another option would be going to a JY and looking for a EFI D21 or WD21 (hardbody or Pathfinder) with a VG, some of them have no EGR from the factory have have a factory block-off plate that'll work on your Z31 after you remove the studs from the plenum. For the exhaust manifold, a 1/2" NPT plug will thread into the hole without much effort even though its not exactly the right threads, and it seals it. The "downpipe" recirculation isnt recirculating exhaust gases, its the "AIV", Air-Inlet Valve. Its simply an electronic air-pump, and pumps fresh air into the exhaust...not exhaust into the intake.

Z31s have single exhaust, on the LHS of the car, and its impossible to do dual without a fuel cell or something similar due to its 19 gallon gas tank taking all the room in the back except for a tiny but of space on the LHS for the muffler. That said, I've seen more S130s with dual exhaust done than Z31s. Well..cant say its impossible, its been done. I wouldn't do it, because the RHS pipes would be super close to the gas tank, and it'd be a PITA to do it with anything but a fart can or straight pipes.

Mallory distributor: Carb rebuild kit, but not for the webers. SU maybe? "Miyaco" Hydraulic Brake parts (wheel cylinder) Asbestos equiped antique brake pads, front: (LOL) New in package DATSUN interior rivets: Seals for something (says on the package, but I forgot what they were): JCC Clutch Slave Cylinder: "Quality Brake Products" front caliper rebuilt kits: The passenger fender has some holes, so I'm going to steal the one from my other 260Z I bought a year ago (it has no floors at all)

Yeah, theres a couple holes there. It was in a garage most of its life, but spent about 2-3 years outside on a concrete slab, which is where the rust came in. Rockers seem ok, but I have a sand blaster at which I'll be sandblasting inside the rockers and such, then getting fresh paint over all of it. Oh yeah, and the drivers window will roll down but not up, the handle jams when trying to go up. So I have to look at that, probably just gonna have to grease it or something. Passenger window is off the tack, so another thing to look at.

Yup, crack free dash! I actually have 2 crack free center consoles, didn't know it was an issue. I have another 74 260Z I bought for $200 a year ago, but the floors are 100% shot in it. I'd like to get it running on the webers, but idk. Like I said, car was last registered in '79 and they were installed in 82. Plans overall, L28ET sometime.

SO, I finally got my 260Z home. When I picked it up today, the guy gave me a TON of paperwork, receipts from over the years etc. The car was last registered in 1979, and the Webers, header, exhaust, etc, were purchased and installed in 1982. I also have the original window sticker. It has 45,000 original miles, with matching documentation, last registered expired in 1979 (stickers still on the windshield). The car has a set of Italian-made Weber 40 DCOEs on a Cannon intake manifold, which was Purchased brand new and Installed in 1982. It also has what I was told was a NISSAN MOTORSPORT header, and also a Pacesetter exhaust (with paperwork of its purchase also in 1982). I can't find any of the paperwork about the purchase of the header, though. I'm quite sure the car was NEVER driven with any of the modifications, but its hard to say. I'm guessing that based on the last time it was registered. Anyone know what these tail lights are for? They were in a box of stuff I got with the car

YUP, thats actually exactly how modern Nissans handle elevation. Modern Nissans utilize MAP and MAF, and use the MAP upon initialization for a BARO reading to determine altitude. Combined with MAP, BARO, and the MAF...they can adapt GREATLY for changes, and stay within optimum AFRs for power. I've seen A32 maximas boosted without tuning it, just forcing air into the engine, blow-through MAF style.

Most map cars use a BARO sensor to determine atmospheric pressure for elevation change, or use the MAP sensor as a BARO sensor prior to startup to determine elevation. BLOZ UP, thats exactly right, which is what we were trying to explain to hoov.

I think the record for most power on the stock Z31 MAF is 440whp atm, but thats with a different tune, larger injectors, rescaling the MAF, etc.

Because the Z31 doesnt have a POS vane air meter like 280Zs and 280ZXs. Its a hot wire MAF, and can compensate a decent bit for changes in AIR FLOW and MASS. With cams, you'll have more air, which is MAF will meter and the ECU will compensate for by selecting the proper load factor. If my ECU can handle a jump from 6.8psi (170whp) to 14psi (260whp) and not run lean, and still run rich as ****, then it can handle cams that are going to add a max of 10-20hp at the FLYWHEEL. The ONLY issue you'll run into with cams not running properly on the stock ECU is if they're designed to work past the 6400rpm rev limit, in which case you have bigger things to worry about than your rich as **** stock tune...like the bottom end and the fact that the VGs stock oiling system us garbage. FWIW, I've run a Z31 with aftermarket cams and the stock tune, at more than stock boost. It ran fine, and the AFRs were still ridiculously rich and safe. Car made more power with the cams than they did with the stockers. So, someone needs to learn how MAF cars work.

All 84-87 injectors are low impedance, with 88-89 being High. Low Impedance ECU and trigger high impedance injectors, but if you use high impedance ECU on low impedance injectors you'll fry the Injector Drivers in the ECU. If you're willing to drive to Savannah, NY I'll give you a MAF for it.

The Z31 turbo ECU is more than capable of adjusting for them. You can make anywhere from 170whp to 260whp on the stock Z31 ECU, and it'll still be rich as a pig at high RPMs in boost. But thats the issue, is its rich as **** and can't be relied on for the most power you can get. Did you change the MAF yet like I told him to to tell you before, and like others have told you? Just curious how this thing is coming.

FWIW, my Z31 always ran like 9.5:1 AFRs at WOT and 11psi of boost, on the stock tune. It idled around like 13.2:1 and 14:1. Plugs were ALWAYS black, but seem to last a long time regardless. I run .035" gap on them, in a VG30ET (9:1 compression)

You cant run 370cc injectors on an ECU tuned for 260cc injectors...

Slightly off topic, but the SOHC VG, and many other newer SOHC Nissan engines, use lifters much like the pushrod V8s, and no pushrods. They are infact legit lifters in these engines, where the cam pushes up on them, they push up on a rocker arm which pivots on the rocker shaft and pushes the valve open...

So my Z detonates under boost. Checking fuel pressure, it can do 30psi idle, 37psi 0"Hg/psi, and at 3psi of boost it was pulling 42psi but detonating! I checked fuel volume, and it does 67LPH at 30psi and 87LPH at 40psi...has anyone done a volume test on the stock pump before? These numbers seem a little low to me :-\ I have a Walbro 255 to go in regardless, but I'm curious what others think about those volume numbers.

Its amazing how much bondo some people use to cover up a tiny spot of surface rust that could have easily been fixed properly...THEN the rust spreads under the bondo, and the bondo cracks.

Every inch of rust is being cleaned to bare metal, if theres a hole new metal is being welded in. This car will be getting brand new floors, etc. More will come soon

began knocking **** out of the floor. Tails out: Fender removal: Started sanding one fender down, had some rust on it.

Nice! Z with snow