Chickenman

Bought the rear caliper SS braided hoses from Silver Mine Motors for $75.00 USD. They sell all of their Big Brake Kit parts separately, which is nice. http://www.silverminemotors.com/datsun/datsun-280z/brake-kit-individual-parts Edit: The rear SS hoses are really well made. All custom made and no additional adapters required. DOT approved. You just fill out the comments section, telling them what calipers you're using and front or rear. Rears came pre-assembled with banjo fittings on the caliper end and the correct Metric adapter that attaches to the factory bracket on the strut. The factory hardline screws right on. New Banjo bolts and washers are included. Best deal I could find. http://www.silverminemotors.com/datsun/datsun-280z/brake-kit-individual-parts/steel-braided-lines

Double check your measurement. A common rear rotor for these kits is a 1985 300ZX USA spec rear rotor. Raybestos 9300R ( I have two sitting in front of me right now ) . But these are 290mm ( 11.4" ). Canadian spec rotors are 10.15" . The Raybestos are a a whole $18.48 USD each from Rock Auto. I got these for my conversion. You don't need drilled rotors. In fact, they are bad for Track days ( They crack ) https://www.rockauto.com/en/catalog/nissan,1985,300zx,3.0l+v6,1209530,brake+&+wheel+hub,rotor,1896 Those look like home made brackets. You can get CNC billet machined brackets for the 300ZX 290 mm rotors from Z Car depot for only $69.95 USD a pair. Awesome deal!! These are made for the Maxima calipers. https://zcardepot.com/brakes/rear-brakes/rear-disc-brake-conversion-caliper-brackets-240z-260z-280z.html

As for parts for old Nissan's. There is a surprising amount still available for them. Drive-train parts are usually no issue at all. Trim and interior parts are the things that are hard to find. BTW, a little tip from your friends up North. Check out Canadian Nissan Dealerships. Our dealership Parts departments can still order direct from Japan. As I understand, USA dealerships cannot order direct from Japan. A lot of parts NLA in the USA and Canada are still available in Japan. BTW, I just ordered a lower thermostat housing for a 1971 240Z. Took my local dealer only 1 week to get it from Japan ( Metro Vancouver Dealer ). 11061-P0300 housing $35.05 CDN retail. My cost $28.04 CDN... from Japan!! The Metro Vancouver area is a hot bed for Datsun fanatics. Lots of 510's up here and Z cars are making a big come back. Many Of the Dealer ship Parts departments are run by enthusiasts, some who raced Datsun's back in the 70's and 80's. Several of the old farts are still involved in Motorsport as well as the new guys. Most of us are starting to retire now. but we're trying to pass the history and enthusiasm on to the next generation of Partsman . Southside Nissan and Coquitlam Infinity still have some of the old time Nissan guru's employed there. I'm a ex-Nissan Partsman. 18 years at Nissan Dealerships till 1993 I worked at New West Datsun, Coquitlam Nissan ( 2 different stores ) and Southside Nissan ( Part Time ) .

Z Cars were great in their day.. ZKars... mehhh. Thing is they are 40+ years old now, You are going to put so much time and effort and love into this car that it would be a shame if some Moron smashes into it. And it will take some time to get reliable. I would recommend getting a good used Japanese car. Something like a Honda or a Mazda 3. The Mazda 3 Hatch backs ( 5 Door ) are awesome vehicles. Reliable, roomy and inexpensive. Plus Mazda generally has higher interior quality than Toyota or Nissan. More in line with Accord level. All the modern safety equipment as well. If you want something higher class, Mazda 6's are a bargain and can compete with much higher priced European cars for handling and Luxury. Save the Z for weekends when you want to go Autocrossing or go for a Cruise with your special gal.....

X 2!! She's a keeper.

^ Above comment about timing chain is very valid. Check the Chain timing and make sure it is correct. If it is, carry on testing. In addition to the above suggestions. 1: Do a compression test ASAP and post up the figures here. You want all cylinders within 15 PSI of each other. It will tell you a lot about the condition of the engine. Engine to operating temp. Disconnect primary leads at terminal connector on fender. That will disable injectors and ignition. Jam Throttle body wide open while cranking. Battery must be fully charged and ideally connected to a battery charger. 2: Do you still have a EGR valve on your engine? EGR valves are supposed to be fully closed at idle. A partially stuck open EGR valve can cause very rough running and sooty plugs. It doesn't take much for the EGR to cause rough running and spit back through the carbs. Old EGR valves tend to carbon up and won't seat closed all the way. It creates havoc with idle and low speed running. Even disconnecting the vacuum hose won't help if the shaft is stuck. The carbon and varnish buildup can physically prevent the valve from seating. Test the EGR valve off the car with a Mighty Vac. A block off plate for testing, temporarily eliminates the problem of a stuck EGR valve. EGR valves are useful though. They reduce emissions and reduce cylinder temps allowing more timing to be run at cruise. ( increases MPG while reducing chance of pinging ) But they must function properly.

^ Uhh.. that would make sense. I've been sick as a Dog with the Flu for the last month, so I missed a lot of posts. Just saw Jai's post on January 19th where she listed what was done in Chronological order.

The " G-Spot " is a myth. Mystical spot meant to frustrate men over the ages...

Replacing the CTS ( Engine Temp to ECU ) has been mentioned several times by various member, but it's not 100% clear if a new one was ever installed???? Has the Coolant Temperature sensor ( two prong ) ever been measured with an Ohm meter or better yet replaced. Bear in mind that the resistance varies with heat. so just checking resistance at ambient temperature may not be adequate. The two tiny prongs are hard to clean. Use a good quality electrical cleaner such as Dioxit ( Spray type ) or Weicon Electrical. Contact spray. The Weicon product ( made in Germany ) is fantastic. Spray it on old corroded contacts and 10 minutes later they look like new. I notice that you mentioned that you cleaned the bullet connections, but what about the connections at the actual CTS? Or was that the TCS you mentioned? Have you checked the spark quality yet? That should be at the top of your list. Your plugs are horribly fouled. Weak spark will do that... as well as a dozen other things, but you have to have good spark quality as a baseline. Edit: I just noticed that the new plugs you installed are the wrong Part number. You Installed BPR5EY-11. Those are 1.1mm or .042" pre-gapped plugs . Those are not correct for a 1975 or 1976 280Z . You should be using a BPR5EY or BPR6EY plug. No suffix ( 11 ) on the end. That is a regular .8 mm or .031" gapped plug. ..031 to .035" is the FSM recommended gap for the 75 and 76 models. You woud gap new plugs to the lessor figure. The weaker Trignition in these units requires the smaller gapped plug. Not worried about heat range difference. I understand why you installed the 5 heat range. Those are the optional Hotter plugs by NGK. That's OK for now, you don't drive the car much. And 6's would foul even worse. Just a note on NGK plug numbers. BPR5EY. The P stands for projected tip. R for resistor plug. Y for V gap electrode. These revisions are are all good for producing better spark quality. Resistor plugs actually produce a stronger spark than non-resistor plug. ( Can be explained later. Techno mumbo jumbo )

Since we're doing comparisons'. I think I may have Rob beat for dirty Brake Fluid when I received my 280Z from PO. It looked like the Brake Fluid hadn't been changed in 20 years. It was filthy black. Flsudhe the whole system and was surprised that I had to replace only 1 rear wheel cylinder due to leakage. And too many JuJubes have the same effect as too many Pistachios... Google tells all!!

My poop was green the other day. Ate too many Pistachios...

Ummm... no. Hope you're flushing the whole system. Brake fluid is a regular maintenance item just like engine oil.

Was it raining? A sticking caliper ( either from pistons or sliding surfaces ) will really show itself when the rotors get wet. Brake pads normally lightly brush the rotor surface, and will wipe away any surface water. If you have a sticking caliper, that rotor will remain wet and there will be a pull to the good side for a second. Once the water wipes off it's usually fine. We get used to this type of thing in the PNW. BTW, if you are not running the rotor splash plates, the problem can get really bad when it rains. Taking my Audi in for a Brake service for this exact same problem. Have a bit of a pull to the right in rain. Pads are sticking a bit in the caliper, likely because of salt and dirt buildup. Normal winter maintenance type thing. Speaking of dirt. If it wasn't raining, you may have got some dust and dirt dirt in between the pads and where they locate in the calipers. That has to be nice and free and all moving surfaces between pad and caliper should have a light coating of Copper-Coat or Never-Seize. Sounds like it's time for a good servicing, including a caliper rebuild. If re-using the old pads, give them a light sanding on some 80 grit sandpaper. Just enough to cut any glaze.

Silver Mine just sent me a notification about a new product. An electric PS kit for the S30. This is one of the most complete kits I have ever seen and the price point is pretty good as well. $900 and it's literally a bolt in kit. Everything is included and fabricated. No cutting or welding involved. http://www.silverminemotors.com/featured/electric-power-steering-kit-for-240z-260z-280z-datsun-1970-1978-s30

Sometimes it's the simplest things... LOL. Good score on the A/F tester BTW. Sweet!!

Well... the good news is that an intermittent problem has now become permanent. That's easier to diagnose.... Be Safe.

Jai: Non working Tach and new plugs get sooty quickly? That could be the Trignition box. First thing I would do is check the spark output as others have mentioned. Pull the coil lead out of the dizzy and hold it about 1/4" from the engine block ( Stat housing is good ). Have a helper crank the engine. You should get a sharp bluish/white spark with a bit of a " Snap " sound. A weak yellowish or orange spark is not good and may indicate a failing Trignition unit. Tach is also triggered through Trignition box. Edit: I can't remember what year your 280z is Jai, but 1975 and 1976 models had very low output Trignition boxes. 1977 and 1978's had more output. If spark is very weak, check the coil wire resistance to make sure you don't have a bad coil wire. If that is OK then I would suspect the Trignition box is failing. Failure after a heat cycle is a common problem with old electronic systems. They fail when they get hot... then the components cool off and it works for a while. Sound familiar? BTW, A bad ground to the Trignition box can cause overheating of Internal components in the Trignition box.... so you may want to check that. It the Trignition box does turn out to be flaky, a 280ZX " Matchbox " Dizzy with the electronic module on the side of the dizzy is a great upgrade. Very strong spark and much more reliable than the old Trignition boxes. Rock Auto has re-manufactured 1980 280ZX distributors for sale for $104.79 out right. Part #31619: https://www.rockauto.com/en/catalog/nissan,1980,280zx,2.8l+l6,1209316,ignition,distributor,7108 The A1- Cardone re-man unit does not come with a Cap and Rotor, but you should be able to use your old 280Z cap and rotor if they are in good condition. If you need a new Cap and Rotor, go with OEM Nissan or buy the Beck Arnley parts from RA. The Beck Arnley parts are usually OEM Japanese made. Keep us informed of what you find. GL.

Jim...my Lord that's a beautiful engine bay.

Point gap should be .018" to .022". I prefer to go with larger figure with new points, as gap will decrease with rubbing block wear. If using a dwell meter, you want 35 to 41 degrees of dwell. More point gap = less Dwell angle. Important note: With new points always wipe a clean sheet of white paper through the closed points to remove any anti-rust coating. Wipe it a few times using just the closed point pressure until paper comes out clean. Failure to do this cleaning can result in the petroleum residue burning and result in a weak spark. An "Old School " teaching that may have not been passed down through generations. BTW, even with timing set correctly, a weak spark can cause backfiring through intake and exhaust.

I kinda ruled out valve lash because his compression figure were all good. How sharp is the spark? You should get a sharp blue SNAP with a good points ignition and HT lead from coil held about 1/8" to 1/4" from a ground. Weak spark or yellowish spark indicates a problem. One thing that is often over looked is the condenser. A weak condenser can cause sooting of plugs. Ignition will also break down at load and can cause backfiring through carbs. Since you recently changed plug leads, triple check that you got the firing order right. It's really easy to swap a couple of plug leads. Engine will run, but will be rough and you often get backfiring through carbs. In original post, owner mentioned back firing through carbs. That is unusual and normally points to Valve issue or ignition problem. Since his compression readings are very good and consistent, that rules out a valve lash problem IMHO. Still, it wouldn't hurt to check. But I think this is more of a fine tuning issue.

Can't see where the other end of your PCV hose connects to, but it should be connected to the Block breather tube as in the following picture. Is it?

A picture tells a thousand words. Can you post a picture of what hose was disconnected?

If it's loose, expand the tube a small with a taper plug. Sometimes a close fitting socket can be used to flare the end a tiny amount. Then use the Loctite Stud Lock.

Haa Haa. Reminds me of the wiring mess I found from PO of my car. PO said it had a " secret Kill switch " installed by his mechanic for the Fuel Pump" . Yep, there it was. A nice shiny toggle switch coming out of the center console by your right knee. It was cleverly labelled " Kill " to fool thieves... Being the curious type, I decided to toggle the switch while driving. Absolutely nothing happened. Car kept right on humming right along. Tracing the wiring found that someone had hot wired this switch direct from the fuse box to the fuel pump.... but they left the original wiring in place!! Not the brightest electricians in town. Lots of other wiring nightmare stories involving CB Radio's, AC " Turbo " switches, " Chromed " alternators that don't work, etc etc. Fortunately the main engine harness was never hacked...

You may have over done the tightness a bit with the prybar. It doesn't have to be that tight. The good news is that it will loosen up. Pour LOTS of oil down the curved side of the chain before starting!! As the chain wears and stretches, the Cam timing retards. Same thing if you shave the head. #1 hole is Zero advance. #2 hole advances cam 4 crank degrees ( to offset retardation from stretching of old chain ) #3 advances Can timing by 8 crank degrees. I've never seen a L seriers have to use hole #3. Advancing cam from " Straight up " install ( Hole #1 ) usually results in a gain of some bottom end Torque, at the expense of some top end power. Sometimes useful if engine is Over-Cammed ( See Racer Brown's articles ). However, you really need to degree the cam to be sure, as has been mentioned. Generally, on a DD or mild Competition engine, I will just install a Cam straight up. Otherwise it's Dyno time to see what the effects of advancing/retarding camshaft really are. .