NewZed

Only posted because the general vagueness around this topic is fascinating. Horsepower numbers, buzz words, lack of specifics. The driveshaft shop at least has some informative discussion on their web site. Hard to tell who's making what and who knows what they're doing.

Beats your guy by 200. http://www.modern-motorsports.com/datsun-240z-280z-complete-cv-axle-conversion.html

One could argue about how warm an engine is after a "few minutes". You can see a possibility for mis-interpretation though.

I would get in to the details. You're looking for something big but it's probably something small. Could just be a vacuum leak at a carb gasket. Spend some time understanding what's really happening. You said it backfires through the carbs when you rev it, but you also said " I did get it to run the other day long enough" implying that it won't even idle. Won't idle and won't rev are two different things. If you're using an E12-80 module use a coil that has specs. close to a ZX. Like ~ 1.0 ohms primary circuit resistance. Be careful with your cam swaps and lash adjustments. The cams don't tolerate certain things and will wipe a cam lobe pretty rapidly. Backfiring through the intake can also be a sign of a wiped exhaust lobe. Make sure that your lobes are still lobes, and not cylinders.

Back at ya. What is your idle ignition timing? What is your mechanical advance curve, approximately? Is your camshaft installed so that lobes open and close the valves at the appropriate times? You're swapping parts, but don't seem to be setting them up to function properly. Timing is more than everything with an engine. Could also just be running lean. That causes intake backfire also.

1. The electrical circuit that controls the lights. 2. Timing: ignition and cam.

JMortensen has written in the past about removing the springs and running the suspension through its travel range to make sure there's no binding. Nobody seems to do it when they have these problems, but it would probably be informative and save a bunch of head-scratching in the long run.

Notice how tall/deep the zcardepot flange is. Might not work with someone else's axle.

Higher height from a lowering kit is an odd situation. Maybe they're on sale for a reason. http://www.thezstore.com/page/TZS/PROD/23-4042 Bumper weight is gone but probably a small effect..

I did miss the title pieces. Best to list things out, for me anyway. You didn't mention the bushings. With factory rubber bushings, the caps need to be torqued with the car down, and rolled to unbind the tire/ground contact, and at ride height. If you torque them with the suspension hanging the rubber will hold the car up.

The lift under the crossmember hasn't been released. It hasn't been rolled to unbind the suspension after lifting. That guy in the picture is very strong and is pulling up on something. You have low profile tires, creating a bigger gap. You installed too-tall springs. There's a few clues. You haven't really given any info about the parts. Springs, isolators, perches...every car has those.

Never mind. You have the signs of a difficult customer.

You're dumbing down a lot of detailed information. "930" is a CV design, with a variety of materials used and manufacturers involved. They're not all the same. "Q45" is a car not a diff. The Q45 came with the short-nose R200, not the R230. The R230 came on twin-turbo Z's and SUV's. "Chromoly" is an over-used word that actually means very little. You can have a "chromoly" axle that will twist like a pretzel if it hasn't had the proper heat treatment. Seems like you haven't really absorbed much of what people have been offering. Look through the nicoclub FSM's to learn about the diff options. If you're not careful you'll buy an R230 kit, for a Q45 short-nose diff, with a 3.13 gear ratio. Not good.

Body Electrical has a clear schematic. I'd post a page number but you didn't post a year.

Early 280Z, late 280Z, or 280ZX? They all use a different EFI relay. If you studied the wiring diagram you'd probably realize that you can work around it. Half of the early Z relay is the fuel pump relay.

If your cooling system is properly filled, how can it accept two quarts more of oil? Have you drained a quart or more of oil from the overflow bottle? Just trying to help you with some details. If you just have a trace of oil in the coolant, and you're losing quarts from the engine, why are there not quarts of oil in the cooling system? Where did it go? You might just be running more oil through the combustion chambers. Worn rings maybe. You'll still be removing the head, among other things, but might be better prepared to fix it.

Probably depends on how you use the 500+ HP. Drifting? The viscous diffs don't seem to last long. Drag-racing? Probably depends on how well the car is set up. Autocross/road-racing? Some people say the viscous diff isn't smooth, just due to the way it works. Not your question but might be relevant. And the 180, 200, and 230 numbers are just the size of the ring gear, which is relevant to ultimate load-bearing capacity but might not be the most important factor in-use. Then there's the size of the external case, which you're talking about here, but may not be relevant. Haven't seen any broken differential housings reported in the R series. Don't forget the number of pinon shafts in the diff itself. Two versus four. They affect durability. Don't overlook the mounting problems with the short nose either. They can exacerbate the half-shaft problems. Misalignment of the shafts under load, from the diff moving, will find the weak spot in a drive shaft. Read through Sunny Z's thread about the path the to the 8.8" Ford diff. He's your role model. He's already done 3/4 of what you're worried about. http://forums.hybridz.org/topic/95937-78-datsun-280z-53-build/ http://forums.hybridz.org/topic/109324-ford-88-irs-conversion/

Metric, US/short, or Imperial/British/long? And, of course, you're talking fractional measurements, like .00003 tons. There are better units of measure out there. Losing not loosing. Unless it's spraying around the engine bay.

Carb to manifold adapters are common. Might be easier and just as effective as building a new manifold. Identify a common carburetor that's appropriate for the engine and build an adapter to your current manifold, or a stock 240Z manifold. What is a "Customs mexican madera" manifold?

The drums are probably worth something to someone. $20 each? I have my own spare set. Pre-77 wheel cylinders are about $50 at the parts stores. Calipers are good for cores. Rotors - depends on condition. Hawk pads - pro-rate to wear. Your thread title can't be much more uninteresting. Probably very few people even looked at it.

Model dependent.

Found some good pictures of the angled back 240Z R180 half-shafts, and the perpendicular 280Z R200 shafts. A backward 280Z mustache bar would push the R200 forward. http://www.zhome.com/ZCMnL/tech/R200.htm

Just check the simple reasons for excess fuel first. Check the vacuum hose to the FPR for raw fuel (blown diaphragm). Excess fuel pressure (the stock FPR is 36.3 psi). Leaking injector. Etc. ECU's tend to short the injector circuit open and flood the engine. Could be the ECU. Is the description below with the ECU unplugged? That would be odd since there should be no injector pulses. Holding the vane closed leans the mixture but also chokes air flow. It should also kill power to the fuel pump since the fuel pump contact will open with the vane closed (as the factory set things up - yours might be modified). You might spend some time in the Engine Fuel chapter looking at how fuel is supplied through the injectors, what the ECU uses to richen the base pulse, what the AFM does, etc. " I had my brother in law hold the wiper on the AFM clockwise, leaning out the mixture, and the car started and stayed running as long as he held it, once he let go, it would immediately run so rich, it floods out. "

19 lb injectors are over-spec. on flow. Mid-40's pressure is over-spec (way) on pressure. You should be running way rich from the beginning. What else did you forget to mention? Are you even using the stock ECU? Has the AFM been "adjusted" to compensate for the extra fuel the out-of-spec. conditions cause? Maybe the cog spring came loose and the vane is free to move.

Must be this car? http://forums.hybridz.org/topic/112393-datsun-260z-turbo-s15-6-speed-technotoytuning/page-12?do=findComment&comment=1159965 Turbo L6?