Zed Head

Found another video that's pretty good. Your first gear would be 2.45 by the tooth counts you showed. I'm calling the gear set the zero gear set but I'm sure that there's another name for it. Can't remember. It's confusing because it is the "4th" in the transmission but has nothing to do with 4th at the shift lever. "Zero gear" - 31 / 22 = 1.409 First gear set 33 / 19= 1.737 Result - 1.737*1.409 = 2.45

I fumbled around with some ratio calculations and your gear teeth numbers come up more like a very close ratio competition transmission. Not a 3.321 first gear. Fourth is always 1:1 on the Nissan transmissions I believe. Tried to find a calculator to make it easy but had to go back to basic math. One hard part of understanding the calculations is realizing that "4th gear" is not really a gear ratio. It's direct drive through the shaft. And, the gears that are called fourth gear are really just the gears that start the power flow through the gear set. They're not really 4th, more like zero. They are part of the ratio calculation for every "gear" that transmits power through the countershaft. Found some illustrations. https://www.artofmanliness.com/skills/manly-know-how/gearhead-101-understanding-manual-transmission/

I don't think that you really know what your ratios are. No offense. Unless you have tiny wheels. The black gear is the 3.54 gear so should give the correct speedo reading. I don't know that the "Nissan comp steel synchros" has standard 280Z ratios either. The ratios you wrote look 280Z but I don't know that there is a "Nissan comp" 5 speed like that. What would be the point? No offense, the numbers just don't fit together. You said you'd like a bit less RPM at highway speed but then said a 3.9 diff might be good. That's going the other way if you really do have a 3.54 now. Also, general warning, beware of California Datsun purchases. His track record is poor.

p.s. And, just because others, apparently, use a residual pressure valve on mixed drum and disc systems it doens't mean that Nissan did. Despite the extensive descriptions that Nissan put in to the brake chapters, the only mention of a difference at the MC between front and back is about the reservoir. The closest thing to an RPV is the check valve that they show. But there is one on each side and they look the same.

Thanks for posting the jalopyjournal page, that was a good read. I didn't actually absorb the whole of the page two of the Wilwood pdf. It was kind of contradictory, with saying only use it for drums, remove it for discs, then put it back in for discs if the MC is lower than the discs. ??? The jalopyjournal discussion is a lot like this one, with many different views, not all of which seem based in actual knowledge. It does seem to show though that there is a reason for an R and an F, and they do differ due to pressure reasons. So hydraulics do come in to play. Seems like it would only be for pedal feel though. Maybe balancing the contact times between shoes and pads, and/or reducing the pedal travel. So F and R do matter, for reasons not clear, therefore, also, importance is not clear. But, since it is a hydraulic matter, if releasing the pressure at the cylinder of the sticking wheel doesn't unstick the shoes in the single drum, then F and R is not the cause of the sticking. I learned something new. It would be neat to put a pressure gauge at the ends of the lines just to see how much residual pressure is maintained. And how long.

At 28 seconds

Probably right, for when you're climbing those really steep hills. Good luck. " If the master cylinder is mounted lower than the disc brake calipers, some fluid flowback to the master cylinder reservoir may occur, thus creating a vacuum effect that retracts the caliper pistons into the housing. This will cause the pedal to go to the floor on the first stroke until it has “pumped up” and has moved all the pistons out against the pad again. A Wilwood in-line two pound residual pressure valve, installed near the master cylinder will stop the fluid flowback and keep the pedal firm and responsive."

I have. The AFM worked fine though. Notice that the ratio is still 1.8, just like if you had 180 and 100. I don't really know how the AFM works so can't say if that means anything.

So that means the MC "issue" is just the fact there's an R where an F is expected. One reasonable explanation for the F and the R is that it makes it easier for the people assembling the cars to put the big reservoir on the right spot. The real discussion might be why they decided to switch the reservoirs. Maybe a decision was made to switch the reservoirs and the switching of the lines followed, logically, but had nothing at all to do with how the stacked hydraulic pistons operated. Anyway, if you're restoring it or you're going to be at car shows, then making it look right is probably worthwhile. Otherwise you'll spend hours talking about F and R instead of the other cool things. I only chimed in here because you implied that the previous owner did not know what they were doing, when they might have actually known exactly how things worked and decided it wasn't worth messing with.

The proportioning valve affects the parts after the valve. The master cylinder creates equal pressure and flow in the lines before the valve. It's difficult to follow this type of thread because the subject changes so often, plus many of the suggestions are not tried. You started with a single sticking brake drum now you're apparently going to reassemble the hydraulics. When you're done the drum will probably still be stuck, because it's most likely not a hydraulics problem. If you're going to take it all apart you might as well remove the line to the wheel cylinder and see if the drum is still stuck. That will relieve any pressure in the wheel cylinder. If your premise is correct the drum will unstick. When you're working on solutions ask yourself why one rear wheel would stick but the other not if the problem was caused by the hydraulics.

Disagree, emphatically. But, good luck.

Thought that you were working on a rear wheel cylinder and/or stuck rear brake (Brakes dragging.), one side only. Not clear what the subject is.

Disconnect the line at the wheel cylinder. Use your pressure device at the master cylinder and see if fluid comes through the line. If it does then the bleeder valve or the wheel cylinder is clogged. If it doesn't then there's a blockage before the wheel cylinder.

Did you press on the brake pedal? Not clear what you're doing. Nothing should come out until you apply pressure.

You could stick a heat gun/blow dryer at one end and just let it run for a while. Isopropyl alcohol (AKA rubbing alcohol) will take water with it but it's kind of a spendy way to do it. Take it inside and prop it in front of the fireplace. Stick it over a forced iar heating vent. Take it to bed with you.

Seems like you would, since the cross-sectional mass ratio (I made that term up) will be different on the side with the drilled balance holes compared to the side without.

Take a brake line to the local auto parts store. The people there will find you one. Or here's some good stuff. 10mm x 1mm keeps popping up, with double flare. https://ratsun.net/topic/43646-510-hard-brake-line/

The vertical metal is tubes that the coolant flows through. The horizontal zig-zaggys are just the fins that dissipate the heat from the tubes. It's not necessarily junk if it doesn't leak. But, besides leaking, the tubes need to be clear so that there is good flow and good heat transfer. Just drain it well and store it away. You might also consider taking to a radiator shop and seeing how much it would cost to refurbish it. It used to be common practice to boil them out but it's not so common anymore. Caustic chemicals and longer-lasting coolants make it not so profitable. I had good luck with a parts store Murray radiator. Many of the aftermarket radiators out there are meant for underhood flash, like cold air intakes and chrome hose fittings. Make sure you know what you're getting. And electric fans don't really add much, they're kind of for show also. A shroud, a good fan clutch, and a good radiator works really well. The cooling problems you read about are from 40+ year old parts, not the design of the system.

Looks like a P. But it would affect both wheels, if it affected anything. But it shouldn't cause a lock-up. An easy check if you're not sure is to open the bleed screw, since it's hydraulic. Releasing pressure would release the shoe. But, that's not going to eb the source of the problem. In the big scheme of things it's the person who understands how the system works who might use the "R" for the front brake lines. Because they would know that it doesn't really matter.

Brake parts cleaner used to be chlorinated solvents. Today's common ones are petrochemicals. Might explain the difference. https://www.berrymanproducts.com/chlorinated-vs-non-chlorinated-brake-cleaner/#:~:text=Berryman Chlorinated Brake Parts Cleaner,best cleaning for brake parts.

Seems like a job for 3D printing.

Those are good posts. I was going to say "every electrical connection". Be prepared to replace the injector connectors if you haven't already. There are much better out there, available at any wrecking yard from Chevys, Volvos, BMW,s etc.

No, you just don't have to see them.

I was showing you the Ignore option without choosing who to Ignore. I would have used my own account to show you but you can't Ignore yourself. so the option does not show.

There are a lot more dealers advertising on the web now. Google or your favorite search engine will find them. Old stock. Actually, this is not a dealer but seems like an outlet for them. https://www.kiacheapparts.com/oem-parts/kia-door-window-belt-weatherstrip-0k01159780?c=bD05Jm49U2VhcmNoIFJlc3VsdHMmYT1raWEmbz1zcG9ydGFnZSZ5PTE5OTkmdD1iYXNlJmU9Mi0wbC1sNC1nYXM%3D