Bloo

No, there isn't. The best you will do with a formula is to check what load range the tires have listed, and attempt to look it up. There may be tables of load vs pressure. Also, P-metric is not the same as metric. For instance P205/75-15 is not the same as 205/75-15. The size is the same, at least in theory, but the way they look at load ratings is different. Without going down the rabbit hole again, the way I remember it is there are load tables for metric tires for a given load range (reflects reality) but for P-metric tires, they are supposed to support some given load across a range of pressures (does not reflect reality). In theory you could look at some table if one exists, weigh the corners of your car, add for passengers and luggage, and calculate what pressures to run front and rear. Maybe even side to side. If you do this, the numbers you get will be in my opinion too low. It will be the softest squishiest setting that can in theory handle the load. If a tire loses ANY air at all, you will be overloaded instantly. Most tire failures are due to underinflation and overloading. When in doubt, more air is always better. I tell you all this with the assumption that you are looking at tires with US market markings, yet knowing full well your location is listed as Australia. It is a deep enough rabbit hole with the tires available in the US, but you could have tire markings in Australia that I have never seen before. @JACK M's method is the best way if you need accuracy. That is how it is done in road racing on pavement tracks, too, although I don't think you can be fast enough with your measurements on pavement to do it the way @JACK M suggested. In my opinion you need a friend to help take measurements. you have to come in from the "track" or whatever your test road is with the tires hot, pull off and instantly have your friend check. One tire per test. They cool off way too fast. In my opinion, you don't have time to get out of the car. We used tire pyrometers, because there weren't thermal guns yet. The pyrometer is slower to use, so the gun works to your advantage that way, but the surface probably cools faster too, and since you are measuring the surface rather than poking in with a pyrometer, that probably works against you. The biggest problem we always had was measuring fast enough. Look for hotter in the center if the pressure is too high, and colder in the center if the pressure is too low. If it is hotter on the outside edge than the inside, you need more negative camber. If it is hotter on the inside edge than the outside you need less. Radials are less sensitive to pressure change than bias tires, because the radials have a reinforcement belt under the tread, and it takes more pressure change to make them bulge in the center. I have no experience dirt racing, so I'll defer to @JACK M on that. It sounds like almost exactly the same method. In the 80s, here in Washington State USA, we didn't use corrosive materials on the roads and 20 and 30 year old (or more) cars were everywhere and got driven year round. These all came with bias tires originally, and almost all of them had radials. Maximum sidewall pressure was the rule, and in the 80s that was either 32 or 35psi. If someone liked it squishy, maybe he got 30psi instead. Never less than that. A few tires were rated 44psi but you hardly ever saw that. Those probably got 35psi like everything else, maybe 40psi if you like it a little crisper (I do). If a pickup (3/4 ton or larger) or trailer tire was rated 50psi max, it got 50psi. After all, It was expected to carry a load. Most of those were still bias at that time, especially trailers, but a few used radials. I still run 35psi in old American rear wheel drive cars with radials installed. It has never been a problem, nor caused uneven tire wear.

Or maybe new cork for a Pontiac face-type front crankshaft seal. The other two don't look like exhaust to me either, but I'm not too sure. Do you have pictures of the flanges they would go against?

Full size Mercury. I'm not near the car to check for details, but it sure looks like the one in my 70 Marauder. This is the center of the dash, not the main dash pad. The second pic is the correct orientation, the hole at the right is a courtesy/map light and points down. The divot at the left in the third picture accommodates a row of idiot lights below the speedometer. This should fit all the full size Mercurys, like Marquis, Park Lane, Marauder, etc. It probably fits 70 too, but I can't say for sure. EDIT: Here's a 69 Monterey from the Internet:

It appears to be, in essence, a generator test set of the type that uses field resistance instead of a carbon pile to check output. This will match a high percentage of the test procedures in prewar manuals. Of special note is the meter that can read down to a tenth of a volt on a 6 volt system (count the graduations between 6 and 7 on the yellow scale). In theory there should be a lot of old equipment that can do that, but it sure doesn't seem to turn up much these days. Setting up 6v voltage regulators with anything less is iffy at best. If I had not already built an analog instrument from scratch(!) with that capability, I would be all over it. Good luck with the sale.

I would connect a multimeter set for continuity to the backup light terminals (since they're smaller), put it in reverse, and turn the switch each way until the circuit opens. Then, pick a spot halfway in-between.

Wait, what? All that crap came from the inside? The normally clean side of the sock?!

I remain unconvinced that modern fuel has to be a problem. The ethanol-laced stuff *IS* horrible, and can be damaging to old cars. I wish it would go away. I however do not believe that one cannot run it in an originally configured car in most cases. More often than not, it is an excuse to not fix a problem that might be rather hard to sort out. On the other hand some cars were always prone to vapor lock. Also some 1920s cars have really overdone the carburetor heat. You did not post make model and year. Beyond "Buick" and "Marvel" I have no idea. You might have an overactive heat riser. But back to your question of what can you do. Run a fuel sock on your fuel pickup if at all possible. Check your fuel line from the tank to the engine with one end plugged and a mityvac at the other, and be sure it holds vacuum. This verifies that it has no pinholes. Don't assume you would see a wet spot from a leak, sometimes you do not see one. If any rubber hoses are used, make sure those do not have pinholes. Use 30R9 fuel injection hose. You don't need the pressure rating, but 30R9 is rated for Ethanol. It is also lined and will not develop tiny cracks which become leaks along the reinforcement strings as it ages. That was a common problem with the old hose used in carbureted cars originally. Make sure your mechanical fuel pump is getting enough movement at the diaphragm. On some cars the cam that drives the fuel pump can wear out and the diaphragm will not have enough movement. Sometimes this can be checked by bolting on a partially assembled fuel pump. Make sure the check valves in the fuel pump hold vacuum. Find some creative way to check them with the mityvac. Avoid at all costs having a fuel pump that has to be "wet" to prime itself. That is a recipe for disaster. On the other hand, a really good pump might re-prime before the carburetor runs dry. Replace any cork carburetor floats. Brass would be nice. If the float is to remain non-brass, use new natural cork (not rubber-and-cork-dust), or maybe balsa wood, or even <gasp!> nitrophyl. Seal the float with cyanoacrylate, or gas tank sealer, or something else that is impervious to fuel and also to ethanol. The original sealer was shellac, and ethanol dissolves shellac, so that won't do.

I would love to see an analysis of this by a chemist. Is there some way to "filter" enough of the black stuff out that it would be effective again, or is it simply a chemical reaction and when it is done, the active ingredient is spent? To test specific gravity in this range, get a kit for wine. I have this one: https://www.amazon.com/dp/B07DTV9HVV

I suspect for any 1937 car the original fuel pump can be taken apart with screws. Get an original one and rebuild it using ethanol-resistant parts. Verify that the check valves hold vacuum while you have the pump apart. Then-N-Now is a possible supplier of parts.

It's never the ECM.

I tried about 3 different brands, but not those. I imagine they are fine. There is not going to be any great advantage to any particular brand of spark plug. The bigger issue is that many brands have discontinued some heat ranges and then lumped all their recommendations onto whatever was left in production. I'm using AC LM-46 in my 1936 208 Flathead. They are lawnmower plugs. The "46" heat range is close to the originally recommended AC K-7, but slightly hotter. AC superseded the K-7 to AC-45 in 1937 if I remember correctly. The LM-46 are non-resistor, and have short insulators and unplated bases like the K-7 did. The short insulators are not an advantage, They are a disadvantage if anything because they could theoretically arc over easier. They sure do look the part though. They are burning fairly clean with no signs of overheating. I think I'll stick with them. If you try the E3 plugs, be sure to let us know how it goes.

Yes. This^^. "I wish I had bought the compressor one size smaller" said no one, ever.

Not hard to do, and your tests pretty much confirm there is something wrong inside the generator.

It's hard to tell. I cant tell how it attaches. It isn't the same shape exactly, but it is similar.

The back ones are just little radiused plates that I assume are supposed to be encased in rubber. They are held on to the hood with one rivet each. It is the same type rivet that is used to hold other parts to the hood panel. Mine are missing the rubber, and from the looks of it have probably been dinging up the paint for 50 years. I had plans to try to try to mold some new rubber in place, but never did anything about it. I didn't particularly want to drill the rivets out unless I was going to repaint. If you find a source, please post it!

There has to be something wrong in that generator. I say take it apart. Look for shorted windings. I know you said you don't have a growler but I got by without one for years. The old books all say to use a 110v test light (I am not advocating that). I tested at 12 volts for years and was never wrong once. Could I have been wrong? Yes, but I never was. Take it apart and check for wires shorting to the case, etc. Check internal wiring to make SURE this is a 12v-to-charge generator. I'm 99% sure it should be, but make sure. One end of the field should be grounded and the other end connected to the field terminal. If it's wrong, one end of the field will be connected to the armature terminal (12v) not ground. Disconnect the field from the case, check for continuity from one end to the other with a car batttery and a 12v test light in series. It should light. Then connect one end of your battery-and-test-light string to the case, and the other end to each end of the winding. Should not light. If it glows or lights up, that is a problem. Then take the armature and connect one end of the test-light-and-car-battery string to the shaft, and probe every commutator segment with the other end. You should not see any glow or light. Then, while you have it apart, in the interest of preventing future trouble, make sure there are no windings that have come loose from the varnish that could vibrate and short to ground in the near future.

Yes, but what do you call positive and what do you call negative on an ammeter? I would call it Ford's way because the generator, when working, is more positive than the battery. That's pretty nebulous though. Who knows what the aftermarket gauge maker did. If it goes the wrong way reverse the leads. I would clip a voltmeter across the battery and full field it again. If the voltage comes drastically up, that ammeter is backwards.

Your book isn't showing a diagram of the system in question. I have owned Fords of this period but never had charging trouble. I don't remember exactly how they work. There are 2 possibilities. Typically GM/Delco systems ground the field terminal to charge, and Ford/Autolite systems send voltage to the field terminal to charge. However, both brands have made systems both ways, so I have questions. Has this car ever been charging normally while in your possession? Do we know it was working and then broke with these parts? Or could there be some wrong parts here? Are the generators and regulators you are trying the correct type for this car for sure? Could the wiring be breached somewhere in-between the generator and the battery? Now with the questions out of the way, and the field wire disconnected from the generator, and the engine on a fast idle, you SHOULD be able to jumper 12 volts to the field terminal on the generator and the car should charge like crazy. You should hear the engine slow down, and you should see charge on the ammeter. Don't leave it hooked up unregulated like that for long. If it charges the generator is good. If not, there are some other things to check. I never put that much faith in the "motoring" test, but I think both of them should have ran well with the field connected to the armature.

Where were you standing when it went left? Standing at the front of the car, looking at the grille and windshield, the fan turns clockwise.

That I don't know. I thought it was generic. There is a generic type of cloth windlace that has been available for decades, and every upholstery and trim shop has or had a sample card of it. I installed a bunch of it in the early 80s. When I last looked at their catalog, Restoration Specialties had that generic type, and also another type with a slightly different weave that I believed was also generic. The second type was more believable for prewar applications in my opinion. The matching wire-on they listed matched the second type of windlace. If Restoration Specialties is making their own, or if it is all being made to order at SMS rather than being cut off of a huge generic roll somewhere, that certainly introduces a whole new wrinkle. I wish I knew the answer.

That's @Alex D.'s generator. You must follow the link to see the other thread.

That would be possible (though extremely rare) on a 64. The 64 models look almost identical to this.

Points triggered electronic ignition was a Studebaker option, and someone mentioned in one of the other threads that it was standard equipment on those top of the line Daytona coupes.

Third brush generators work like this: There are 2 circuits, the armature and the field. The armature does the charging via the 2 main brushes. One main brush is grounded, the other main brush connects to the output terminal, and charges the battery through the cutout relay when the cutout relay points are closed. The field is just an electromagnet in the outer frame. Controlling the field controls the generator output. There is no voltage regulation on a third brush and cutout system, only current regulation and it is a bit dodgy. The field is powered by the third brush. The setting of the third brush determines the voltage the field gets. RPM also affects this. The more voltage the field gets, the more current the generator as a whole puts out, so the third brush setting is used to set the output current of the generator. The other end of the field winding in the frame is grounded normally. Since you have that thermal cutout thing, I would guess that the ground end of the field winding is grounded when the generator is cold, and if the generator starts to overheat, the points on the thermal cutout open putting the resistor in series between the ground side of the field winding and ground. Some voltage is dropped across the resistor, and that means less voltage for the field. Less voltage for the field means less output. Less output could save the generator from overheating. If the resistor was missing or burned open, the generator would stop charging when the thermal cutout points opened from excessive heat. Never run a third brush generator with no battery connected. There is no voltage regulation, and the voltage will soar. The field is running on part of that voltage, limited by the location of the third brush, but not limited enough. When the voltage soars, it will try to burn out the field, and probably succeed. The "motoring" test you referred to is done by connecting 6 volts to the output terminal and the case, using the polarity (positive or negative ground) as used on the car. Belt or drive mechanism should be off so it can spin. The generator should run like a motor. I don't know how useful the test really is, but if the generator fails it there is definitely something wrong. It wouldn't find the open resistor, because the generator would most likely be cold. There was a thread about that resistor on a Cadillac recently. I'll come back here and post a link if I can find it. I would expect the resistance to be really low. It wouldn't surprise me at all if it is less than an ohm. It is probably made of Nichrome, and probably increases resistance as it gets hot. Making or rewinding a resistor should be doable. EDIT: HarryLime's got it.

Electronic ignition (points triggered).