The ratio in the rear end was certainly different for each application, but the planetary gear sets inside the case were all the same. The ratios for all THM350's were 2.52:1 for first gear, 1.52:1 for second gear, and 1:1 for third. The bigger THM400 (for big block engines) had very similar ratios. A light weight version called the THM200 was designed for 4 and 6 cylinder engines with a slightly taller ratio set. They blew up like some of my tubes, hot and messy, with red stuff everywhere!
All the TurboHydraMatic transmissions used a vacuum modulator to control the shift points with engine vacuum. Light throttle, high vacuum, low RPM shifts. Foot on floor, near zero engine vacuum, high RPM shifts. Old school fix, a vacuum bleed made with an aquarium air valve makes for adjustable shift point. Better alternative, an aftermarket adjustable vacuum modulator.
I had the THM350 in my van tweaked to where it would shift from 1st to 2nd at almost 6000 RPM when the throttle was floored, and 2nd to 3rd around 5200 RPM. Those points are also determined by the air flow capabilities of the carburetor. A carb that's too small for the engine will start to develop engine vacuum at high RPM due to the airflow restriction causing the trans to shift early. A crappy air filter system can change the shift points too.
I was lucky enough to get a new instructor in his first year teaching high school electronics. He oversaw the construction of the big Tesla Coil that got us banned from the science fair, and actually bet me that I could not make the outer envelope of a metal 6L6 tube glow red. It stunk up the entire vocational wing of the school, but I won that bet.
Good to know 🙂
The 020 in the VW had many different ratios and codes so I guess that's what I was thinking of. I had that Impala and then many VWs before going with BMW. The BMW gearbox is similar in that the ratios were the same but the differential had different gearing based on the engine. If you put the diff from a 320i on a 330i, the top speed will be lower, and it will drink fuel, but it'll be FAST LOL 4000 RPM at 120km/h is silly though... It'd be like driving my car in 4th instead of 6th 🙂
The 020 in the VW had many different ratios and codes so I guess that's what I was thinking of. I had that Impala and then many VWs before going with BMW. The BMW gearbox is similar in that the ratios were the same but the differential had different gearing based on the engine. If you put the diff from a 320i on a 330i, the top speed will be lower, and it will drink fuel, but it'll be FAST LOL 4000 RPM at 120km/h is silly though... It'd be like driving my car in 4th instead of 6th 🙂
The way to safely discharge a CRT is this.....
Clip a ground wire to the metal mounting frame of it.
Clip the other end of the wire to a long, insulated flatblade screwdriver.
Stand on an insulating mat.
Slide the flatblade slowly under the rubber anode cap - listen for a snap/spark.
hold for a moment..... done.
Come back half an hour later and it will have built up enough voltage from charge stored in the imperfect coating on both sides of the CRT glass to seriously shock you.
The resulting zap can trigger an involuntary muscle contraction which can result in serious injury. I still have a 2 inch scar on my arm from being sliced open by the convergence board on my high speed retreat from a TV set in 1969. A trip to the ER for stiches was only the beginning of the fun. The infection that ensued about a week later required the wound being reopened for drainage.
Anyone care.....anyone even have a CRT TV or monitor today....mine all got wasted as rifle targets. Did you know that CRT's will float, and make a cool geyser when shot?
It's all ancient history now, but then I am considered ancient by some of my friends.
The FWD Dodge cars of the 1980's did have options to play musical gear sets. I paid a lot of money to a man named Shelby for some magic gears and other cool go fast parts. He had follower Iacocca to Chrysler in the 80's and made some fast 4 cylinder FWD cars before they were trendy. With his intercooler, engine and transaxle mods, and a whole lot of boost out of the turbo I could beat a 5.0 Mustang in the quarter mile hitting the rev limiter at the top of 3rd gear going through the lights. On an open road 4th would get me to the point where I could just make enough boost in 5th to keep pulling to a 154 MPH top speed imposed by the rev limiter at 7200 RPM.
One tire size bigger and it didn't happen. Unfortunately the required tire size was only found as the optional size for a VW Scirocco for a few years in the mid 80's, and only made by Pirelli. Once those cars fell out of fashion the tires disappeared. Not that I needed to go 154 MPH anyway, but the look on Mr Gold Chains in his shiny new Vette when this crappy old Dodge passed him was priceless.
BTW, this thread is about todays youngers being more stupid.....are we not discussing our own stupidity, and thus disproving that point? Didn't we all do stupid stuff when we were "younger?" Would I dream of going 140 to outrun the cops, or 154 to best a disco bozo in a Vette today.....no, I'm now one of those grumpy old farts that talks about how stupid kids are....
Tubelab, in all my years of servicing, I've never had such an episode with CRT tube sets.
And I've changed/replaced hundreds of them.
Back around 1994, Zenith had hoardes of 23 inch table model sets (made in Mexico) with CRT's that failed, and took out the whole chassis too. - under warranty even.
I was busy as all hell with customers coming in with those sets.
Of course, Zenith paid dearly, then went bankrupt, and LG (originally Lucky Goldstar)bought them out to save the name.
See what happens when you decide to outsource assemblies?
And I've changed/replaced hundreds of them.
Back around 1994, Zenith had hoardes of 23 inch table model sets (made in Mexico) with CRT's that failed, and took out the whole chassis too. - under warranty even.
I was busy as all hell with customers coming in with those sets.
Of course, Zenith paid dearly, then went bankrupt, and LG (originally Lucky Goldstar)bought them out to save the name.
See what happens when you decide to outsource assemblies?
“82 that trans am was pathetic at best with like 150hp 305cui.....“
Funny, my diesel car gets 130 BHP from 1500 cc on a 3 cylinder engine
64 MPG on the highway about 45 in town. It’s the second Citroen Grand Espace C4 I’ve bought. Moves afoot here in the UK to ban petrol/diesel cars and only allow electric from 2030 so I think this will be my last fossil fueled car. I’ll be 74 if Im still around then, and it will be an electric Merc so see my twilight years out in.
I had a Ford Mondeo in the early 90’s that did the same 130 BHP power on a 2 litre engine.
That progress for you.
Funny, my diesel car gets 130 BHP from 1500 cc on a 3 cylinder engine
64 MPG on the highway about 45 in town. It’s the second Citroen Grand Espace C4 I’ve bought. Moves afoot here in the UK to ban petrol/diesel cars and only allow electric from 2030 so I think this will be my last fossil fueled car. I’ll be 74 if Im still around then, and it will be an electric Merc so see my twilight years out in.
I had a Ford Mondeo in the early 90’s that did the same 130 BHP power on a 2 litre engine.
That progress for you.
I only worked in a TV repair shop for three years, 1968 - 1971. I learned to connect a clip lead from the ultor electrode to chassis ground for at least an hour before attempting to remove the CRT. Dropping one of those onto the concrete floor could seriously ruin your life....if you lived.
For those "youngers" who don't know what we are talking about the CRT (picture tube with the glass face of the TV) has an "aquadag" coating on the inside and outside of the glass. The inside coating is connected to the HV supply and the outside coating is grounded. The ground is either fingers touching the coating in a few places, or a spring stretched across one side. Together these coatings form a capacitor that is the filter cap for the 20 to 27KV HV supply. The 'dag coating is not a perfect conductor even when not damaged. It is somewhat resistive, thus making this cap somewhat imperfect and subject to charge storage effects. The coating is also easy to scratch during installation of the tube.
Ever meet a color TV from the 50's with a metal CRT. The metal part runs on the 25 KV supply. The coated plastic shrouds are the capacitor. The plastic dielectric used in the 1950's sucked, and these shrouds can zap you days after being removed from the TV.....and that's in the Miami Florida heat and humidity.
Other than an implosion, how does a failed CRT take out the whole chassis. I have seen the arcing caused by loss of vacuum blow up some parts in the video driver circuitry, but the whole chassis...
The shop where I worked in high school was a Philco (Ford) authorized warranty shop. The weirdest thing I ever saw was a deflection yoke that had arced internally and got hot enough to break the neck of the CRT causing the whole assembly to fall in the middle of the chassis smashing a good bit of stuff. Philco wanted Polaroid pictures of this mess, but in the end paid for the entire repair.
At the time a lot of TV sets were still being sold in automotive repair centers and tire stores. Philco sold through the Firestone stores and offered financing to people who otherwise could not afford a nice 21 inch console color TV. Many of these residences did not have air conditioning, so the TV lived in ultra high heat and humidity, and often dirty conditions. This was the case in the flaming neck incident. Bug infestations (ants and cockroaches) made for some seriously fried HV boxes and burnt flyback transformers. Red fire ants are an excellent conductor and can explode leaving telltale brown marks around the 5U4 or 3DG4 socket.
That's basically what I did but without the wire. I slid the screw driver under the cup, and brought the screw driver toward the chassis. There was always an air gap 🙂
I was probably about 15 at the time. The TV was 19 or 21 inch colour.
Now, I have zero need to play with CRTs. I haven't even seen one in the trash for a couple of years, but I did find a 46" Sony Bravia XBR 1080 LCD that works perfectly...
I used to play hammer toss with mine. Surprising how hard you can throw a HAMMER at a 14" CRT monitor before it will break. I'd never seen a hammer bounce off glass and fly 20 feet before that.
I did similar things with those VWs. I never went crazy, but the stock VW GTI from 1983 was faster than the Trans AM out of the factory - that made for some fun "tour de stoplight" moments. The original Omni was a cheap copy of the VW Rabbit anyway. Even the 1.7L engine was licensed to Chrysler from VW, but they proceeded to make it "cheaper" and leave out main bearings, fuel injection, lambda etc. A true POS compared to the actual VW engine.
Then Chrysler put their own motor in it and it wasn't such a dog although those engines were poorly designed too. Most were in the scrap yard within 10 years. 🙁 Glad you had fun with one. Being younger, I didn't start "doing up" my cars until the late 90's. Even then, do you know how many upgrades I got from the scrap yard? I Loved VW for that. The suspension from a 1998 Golf will bolt up to a 1985 without mods... Warm up regulator from the Audi 5000 made more power, as did the throttle body. Intake from a newer VW Fox bolted onto my old Jetta but flowed much more air etc. Even up to the MK4 Jetta with the first 1.8t engine they offered, that block still has the bolt holes to be fitted into an MK1 chassis!
It was always set up as a sleeper though 🙂 You wouldn't know it wasn't just another boite de la marde.
Totally. When I was 15 and stupid, I drove a 70km round trip to pick up a friend who was coming to visit. I drove there by myself on the highways without any incident (or insurance/license) during the afternoon rush hour. 42YO me looks at 15YO me and says "Horseshoes, buddy! Horseshoes! (up your cul)"
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We must be more stupid in the UK as we have had sleeved pins since 1984
Or maybe we are just quicker at being stupid
Brian
With little embarrassment I am saying that would be me. But I do not watch TV too often. Dad bought Valve based CRT TV at around '72, then around '84 we had Nordmende TV and finally in 2001 I bought Sony Trinitron. Which is still working. So all CRTs. TV is placed in rugged atmosphere near our room window where sunlight, rain moisture and cold are often present. Dont know how much LED TV would survive. But change is inevitable in coming months I think. Here max 3/4 years of life is predicted for LED TVs.
Regards
If it makes a difference, I have a Sony LCD from 2006? that still works, and a cheap RCA that's lasted for 5. I'm using a "Philips" TV (read Chinese) now and it's worked 24/7 for 2 years so far... I've only had computer monitors fail - one of which was replaced under warranty 4 times before I sold it, and another that worked 24/7 for 2 years but I turned it off for 2 week while I went out of town. A segment of backlighting stopped working.
When the rash of bad 23" CRT's in 1994 happened, apparently they shorted in a way that damaged the video driver board and flyback too.
It was Zenith's Service Bulletin to just replace the chassis and be done with it.
So each CRT that came in also had a new chassis packed with it.
All those CRT's were made in Mexico, something Zenith learned the hard way.
I've got 3 CRT TV sets in the house.
A 2005 Samsung 30" "widescreen set that weighs 120 LBS. - works fine.
A 1990's 13" Daewoo in the back office, still chugging along.
And a 1989 10" Panasonic on top of the refrigerator in the kitchen. - also plays perfectly.
Of course, the small older sets need those digital (DTV) boxes, and all the TV's in the house are fed from the roof antenna system that I installed back in 2009. - hell, I get 60 broadcast channels for free, only watch a couple.
I refuse to pay for cable, to me it's crap.
Stored in the closet is a Samsung 15" monitor for PC, works, but has been replaced by an LCD Dell on my main desktop.
My parents bought a 23" Zenith hybrid in 1972. It lasted until 1991
when it was going thru 1 horizontal output tube a year and the price
of the tube exceeded $36.00 USD. They then bought a Philips 30" which
still works with only one repair, 1uF coupling cap in the
horizontal driver stage. Zenith has been owned by Lg electronics since 1999.
Oh, I still have 2 of those DTV boxes and still use an antenna.
when it was going thru 1 horizontal output tube a year and the price
of the tube exceeded $36.00 USD. They then bought a Philips 30" which
still works with only one repair, 1uF coupling cap in the
horizontal driver stage. Zenith has been owned by Lg electronics since 1999.
Oh, I still have 2 of those DTV boxes and still use an antenna.
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Tubes are in sockets for easy replacement, obviously.
But here's the thing... that output tube continually failing was telling you that something "under chassis" was at fault and needed addressing, which is something most people don't seem to understand.
And that is what fed the tube industry - the common ignorance of the public regarding electronics.
As for the Zenith/LG situation, the actual turnaround started because of the 1994 fiasco when Zenith filed for bankruptcy due to those faulty sets.
Ehhh, it was 29 years old and had other problems, I still consider that it was a good TV as we had almost 3 decades of use out of it.
Yes indeed, it goes to show how things were made to last and you got your money's worth from products.
My best friend purchased (after my suggestions) a Panasonic "Prism" 27 inch set back in 1988.
It was then their premium model with an awesome sound system built in, and loaded with features.
I believe it cost about $1000 back then. pricy.
That set lasted 19 years flawlessly, until one day the power supply fried itself with a bit of smoke coming out of it.
I pushed, and they got a Panasonic LCD set, now 14 yeears old, and still flawless.
And in 2013 another Panasonic LED set going strong.
I swear by that "Viera" line they make, I own one too, and the reason is after being in the shop for many decades I rarely ever saw them come in for any trouble.
They're just damn reliable sets.
So, as as a seasoned old TV repairman, I naturally wanted to invest in something reliable.
Shame that Panasonic stopped (for now) selling them in the USA a few years ago.
But I think Canada still sells them... any Canadians here can attest to that?