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BraveUlysses posted:I dunno what happened, I think I've seen the owner sitting in the vehicle in that area while it idled...might have been living in the truck? The rare person that financed a truck for only 60 months.
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Jan 24, 2022 03:53
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I love seeing all these ram commercials about how badass they are. Yet any time I watch car repair YouTubers it's 'well I'm good at replacing this because this is a common issue with dodge'
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Jan 24, 2022 14:09
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bonelessdongs posted:Do you have opinions on Jan Eggenfellner trying and failing to put subaru engines in planes? I remember one of his excuses was EFI just not being up to the task of engine control like carbs and magnetos are Subaru engines suffer the same problems as any other car engine in an airplane. The operating requirements are nearly completely different. Instead of mostly requiring low power output with occasional spikes, aircraft engines are pretty much asked to operate above 70% power for their entire lives. This is generally fine, because aircraft engines are kinda designed to be huge, loafing hi-torque engines. To get the same power from a car engine, you’re going to have to spin the bejeezus out of it… …Nearly any car engine conversion is going to involve a gearbox. Geared aircraft engines are certainly not unheard of (basically every radial is a geared engine,) but most of the time with an aircraft engine, you’re starting at say, 3400 engine rpm, and reducing to 2800 prop rpm. So an ~18% reduction. This means that your gearbox is going to be pretty lightly stressed, and isn’t going to weigh much. Most geared engines that I’m aware of eat the reliability penalty by way of reduced TBO intervals. It’s worth it for the increased power output. A gearbox designed to go from a 6500rpm output shaft to a 2800rpm prop is going to have much higher internal stresses. You’re going to need a much beefier case and gear train, and probably a much more complex one in order to be reliable. And remember, reliability is kinda important in this application. This is all before you get to the reliability impacts of the engine running at 5-6000rpm all day long. The Subaru engine market came along in the nineties as a replacement for the VW Type 4 in homebuilts. Now, I loving love air cooled VWs, but I’m not going to drive an air cooled on a road trip in TYOOL 2022, let alone loving FLY ONE anywhere further than the pattern. These crazy fuckers see a VW or Subaru flat four, squint at it, and say “hey, airplane engine. It’s flat, and it has cooling fins. Totally the same thing.” TLDR: I am unsurprised that someone attempting to market a Subaru engine as a production aircraft engine said that fuel injection and electronic ignition was too complex, because they have already ignored the 900lb pink gorilla wearing a loving tophat guarding the door. If you asked him, he’d probably say something along the lines of “you just can’t work on a fuel injected engine like you USED TO BE ABLE TO.” …And then he’d put his MAGA hat on.
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Jan 24, 2022 15:08
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Gearboxes don't have to be that complicated or heavy. Look at literally any turbine helicopter application. 10,000RPM to a few hundred. Heck the Purepower series by Pratt have a gearbox for their front fan. Marketed to last the life of the engine without service. Modern planetary reduction gearboxes make this possible. Now if we want to address the issue here, Subaru motors have very anemic journals on the crank, they like spinning bearings in high output applications. Ain't no modernization or redundancy going to fix that. Heck my built FA motor had its oil galleys increased in size to deal with the issue.
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Jan 24, 2022 15:27
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How come it isn't more common to use diesel engines, TDI, etc. They're happy to run all day at 2800rpm, make gobs of power, and will be running when only cockroaches are left on the planet. Oh, and you can burn JP1 as long as you add some 2-stroke oil or something for lubricity.
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Jan 24, 2022 15:43
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chrisgt posted:How come it isn't more common to use diesel engines, TDI, etc. Air density? Turbo reliability when they're having to shovel that much more air in?
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Jan 24, 2022 15:47
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chrisgt posted:How come it isn't more common to use diesel engines, TDI, etc. I'd take a shot at the RPM band not being wide enough for throttling applications. Though that doesn't stop the turboprops. Just adjust the prop pitch there
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Jan 24, 2022 15:50
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chrisgt posted:How come it isn't more common to use diesel engines, TDI, etc. Comes back to the reasons MrYenko posted - a shrinking GA market and buy-in costs that make the eye-watering price of a Lycoming look cheap. There are companies pushing for automotive-to-aero diesels, and it's certainly a great solution on paper with the combination of "uses a fuel already easily obtained at airports" and "no lead". But since the FAA continues to drag its rear end on eliminating leaded avgas, the same old engines are still available. The few people who are buying new engines in 2022 still prefer the engine that's been around so long you can predict the maintenance costs down to the penny.
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Jan 24, 2022 16:04
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tater_salad posted:I love seeing all these ram commercials about how badass they are. Yet any time I watch car repair YouTubers it's 'well I'm good at replacing this because this is a common issue with dodge' Dodge will give you a good, usable truck. Sorry, parts of a good, useable truck. Ok, ok. Dodge will give you one really good part and the rest falls apart around it. The square-body Ram was about the most unimaginative design possible, which might be a big part of why they sucked hind tit on sales. The 2nd gen Rams innovated but used some proven parts early on, and everything else really did fall apart around them. The 3rd gen strayed even farther from God, but the ergonomics were really good (and they sold very, very well). What you see of these older Rams are the survivors. When everything is in spec, put together correctly, and well taken care of, they last and last. All the same Dodge problems remain: front suspensions need rebuilding every 50-75k miles, the transmission could last forever or it could fail every 30k, the interior parts are brittle as glass, the electronics are... well, one step above Lucas. Parts are cheap and readily available, working on them is kinda easy, and you are never far from a mechanic that's done a ton of work on them. There's things on mine that I know are so fragile they may as well be consumable parts. Those parts I buy off Amazon, next day delivery. Rams are not the worst choice if you want a low-spec work truck or something insane, like the SRT-10 Ram or a diesel that produces 1000lb/ft of torque stock. For everything else, there's Chevy/GMC. Don't buy old Rams (because I want them all for myself).
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Jan 24, 2022 17:37
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um excuse me posted:I'd take a shot at the RPM band not being wide enough for throttling applications. Though that doesn't stop the turboprops. Just adjust the prop pitch there This is the best case scenario for a diesel engine. Let it run at a constant 2500-2800 RPM and use a variable pitch prop. Then you can tune the injectors and turbo size for that speed range and have a very efficient setup. Air density shouldn't be a problem, just get a turbo that can handle whatever your constant projected peak boost is going to be. Say you run it 10psi at sea level on a standard day and 25psi to turbo normalize at a higher (density) altitude. Not hard (but maybe expensive) to find a turbo that can handle 25psi (or whatever) at 100% duty cycle. IOwnCalculus posted:Comes back to the reasons MrYenko posted - a shrinking GA market and buy-in costs that make the eye-watering price of a Lycoming look cheap. There are companies pushing for automotive-to-aero diesels, and it's certainly a great solution on paper with the combination of "uses a fuel already easily obtained at airports" and "no lead". But since the FAA continues to drag its rear end on eliminating leaded avgas, the same old engines are still available. The few people who are buying new engines in 2022 still prefer the engine that's been around so long you can predict the maintenance costs down to the penny. Yea, i'm just surprised we don't see it more in the experimental world. People always just go use the same things over and over. The big draw to me is no gearbox because the prop RPM is also the engine's peak torque RPM. And the fact that I have a hardon for diesel engines....
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Jan 24, 2022 17:40
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chrisgt posted:
"In today's news, a NE US man was arrested off the coast of Newfoundland while testing a six-wheel-drive, diesel powered, amphibious airplane. Our team was able to obtain a statement from the man, "Once you go compression ignition, you never go back.", before he disappeared across the border in a cloud of blue smoke and Toyota transmission parts."
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Jan 24, 2022 17:53
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My wife's family consistently buys Chrysler/Dodge/Jeep vehicles and they are constantly making GBS threads the bed. I don't understand why they won't try something different.
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Jan 24, 2022 19:19
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The only successful auto engine to airplane engine conversion is the Austro mentioned in the video upthread. And that happened largely because the owner of the airframe manufacturer willed it into existence. And even there, the production numbers are minuscule.
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Jan 24, 2022 19:25
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I have a small diesel hatchback and it's quite noticeable in the handling how heavy the engine is. i guess that would make experimenting with diesel engine in a small aircraft a pretty substantial project.
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Jan 24, 2022 19:41
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stinch posted:I have a small diesel hatchback and it's quite noticeable in the handling how heavy the engine is. i guess that would make experimenting with diesel engine in a small aircraft a pretty substantial project. The most attractive part of aircraft diesels is that they run on Jet A, which is available globally, unlike 100LL which can be hard to get outside CONUS.
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Jan 24, 2022 19:43
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stinch posted:I have a small diesel hatchback and it's quite noticeable in the handling how heavy the engine is. i guess that would make experimenting with diesel engine in a small aircraft a pretty substantial project. Can aircraft understeer?
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Jan 24, 2022 19:45
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MrYenko posted:The only successful auto engine to airplane engine conversion is the Austro mentioned in the video upthread. And that happened largely because the owner of the airframe manufacturer willed it into existence. Successful as in mass produced? Back in the day, lots of homebuilts ran on Model T engines, with a smattering of various motorcycle engines as well. The Corvair engine is also fairly popular. Plus the aforementioned VW air-cooled.
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Jan 24, 2022 19:46
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Plastic_Gargoyle posted:Successful as in mass produced? Back in the day, lots of homebuilts ran on Model T engines, with a smattering of various motorcycle engines as well. The Corvair engine is also fairly popular. Plus the aforementioned VW air-cooled. “Mass produced” kinda stretches the meaning of the word even with Austro. It’s generally taken to mean “available factory-new in a certified airplane.”
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Jan 24, 2022 20:35
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Failure prevented perhaps? My brother is swapping ATS-V brakes onto his '01 Camaro, and a line lock. Pretty nice 4 piston Brembos on the front. I helped him flush/bleed the system. This is what came out. (click for bigger) 
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Jan 24, 2022 21:11
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MrYenko posted:A gearbox designed to go from a 6500rpm output shaft to a 2800rpm prop is going to have much higher internal stresses. You’re going to need a much beefier case and gear train, and probably a much more complex one in order to be reliable. And remember, reliability is kinda important in this application. Sure, you can say that all you want, but I still want to strap two EZ30Ds onto an experimental with PSRUs built from NP241C transfer cases (ratio: 2.72, would give you 2400rpm at 6500 engine speed) and Chrysler 8.25 or Dana 70 axleshafts.
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Jan 25, 2022 00:22
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I just saw a video where some aeronautics guy explains why new engines don't happen for GA https://www.youtube.com/watch?v=_k1TQGK3mZI
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Jan 25, 2022 00:36
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paul bertorelli is not just "some aeronautics guy," he's the best aviation youtuber there is. https://www.youtube.com/watch?v=f6q2VKsvQEQ just look at how many stripes he has!
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Jan 25, 2022 01:25
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If you have even the smallest whiff of interest in "airplanes" you owe it to yourself to watch Paul Bertorelli's videos. I can only dream of being so deservedly cranky when I grow up.
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Jan 25, 2022 02:27
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madeintaipei posted:There's things on mine that I know are so fragile they may as well be consumable parts. Those parts I buy off Amazon, next day delivery. I really feel like that's not unique to any heavy duty truck. You just have to pick your particular "this is stupid" design decision and roll with it. Ford put four cup holders in my console for some unknown reason and three of them are used to carry your usual fiddly bits that loving break all the time. I don't know what genius thought that a little multipart windshield nozzle should live right over the turbo on the hood but that's just the beginning of dumb poo poo on those trucks.
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Jan 25, 2022 02:40
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Sagebrush posted:paul bertorelli is not just "some aeronautics guy," he's the best aviation youtuber there is. in a world without visible downvotes on youtube, how can we be sure this man isn't leading people to their deaths?
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Jan 25, 2022 03:43
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meltie posted:Can aircraft understeer? It's typically called CFIT. Edit: As soon as I saw that dude's stripes I became a fan.
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Jan 25, 2022 03:44
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Haha I like that guy
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Jan 25, 2022 04:53
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sigh was hammering out these loving seals and...sigh
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Jan 25, 2022 05:27
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BraveUlysses posted:sigh I'd probably glue the new seal in. It's the last replacement for that valve cover, but who cares. If it doesn't leak, just run it
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Jan 25, 2022 13:38
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kastein posted:Sure, you can say that all you want, but I still want to strap two EZ30Ds onto an experimental with PSRUs built from NP241C transfer cases (ratio: 2.72, would give you 2400rpm at 6500 engine speed) and Chrysler 8.25 or Dana 70 axleshafts. Let me introduce Bob Pond. Bob Pond joined the Navy in 1942 and became a Naval Aviator. He never left the US during the war, but got quite a bit of multiengine time, eventually getting rated in every multi-engine aircraft in the USN. Leaving the Navy in late 1945, he went back to college, got a business degree, and generally lived the stereotypical postwar-boom life, building the family floor grinding and polishing equipment business into an international concern, and generally being comically successful. In his free time, Pond became interested in auto racing and stayed extremely active in aviation, though he never went to the airlines like he expected to leaving the Navy. He founded an air museum in Flying Cloud Minnesota, and when he retired to Palm Springs, moved the (significant) collection with him and cofounded the Palm Springs Air Museum. He often boasted that his museum was a flying museum, and during his lifetime everything that was owned by the museum outright was kept in flyable condition. (They have a significant number of non-flyable aircraft on loan from the Navy.) I swear this is thread-relevant, bear with me. In 1966, at a sleepy airfield outside Reno Nevada, the first event of what became the premiere air-racing league was held. Reno has multiple classes, all competing on a closed circuit. Today we’re going to talk about the 800lb gorilla; Unlimited. Six laps around a course that’s just a touch under 8 statue miles. Unlike most auto racing outside of land speed racing, Unlimited class air racing is just what it says on the tin. Piston engines (there is a separate class for jets that is essentially an L-39 spec class,) run what ya brung, fastest guy around the pylons wins. What sets this apart from say, Red Bull is that it is single class, live, wingtip-to-wingtip racing. It is loving intense. Since 1947, air racing generally has been dominated by surplus WWII fighters, with P-51s making up the majority of the field, and owning the lions share of the championships, but with several notable outliers such as Rare Bear, an F8F Bearcat having several streaks of dominance over the years and several different Hawker SeaFuries doing very well historically. It’s rough on airplanes, but even tougher on engines. Engine swaps are common, with several P-51s moving from Packard V-1650 Merlins to Rolls Royce Griffon 58s and contrarotating propellers harvested from retired Avro Shackletons. All of these engines are routinely pushed well into the obscene-levels of boost pressure to make the power needed to compete. A normal V-1650 is rated at 60” of Mercury manifold pressure and 3000rpm for takeoff, and 46”/2700rpm continuous. During a 2017 FAI outright speed record attempt (so not race conditions, but drat-the-engine-let’s-go-fast conditions,) Steve Hinton Jr’s crew chief mentioned that they would make the pass at 111” and 3400rpm, increasing to 120”/3400rpm as the aircraft dove for the deck and through the entry gate. Also, this makes a hell of a noise  So in the late eighties, early nineties, lots of Mustangs are getting cut up for racing, there are quite a few crashes, and the once-plentiful Packard Merlin is not so plentiful. Bob Pond looks at this and says “I can do something about this. We can do better.” Enter the Pond Racer.  Pond approached Burt Rutan about the project, which was formalized as the Scaled Composites Model 158. Powered by a pair of Electramotive turbocharged 3L V-6 engines derived from the Nissan VG30 of all things, the Rutan brothers and Pond wanted to build an airplane capable of not only competing with the big boys at Reno, and of taking (and holding) the FAI propeller driven speed record, but to use no existing warbird airframe or engine components in the process. (There was a competing project called Tsunami that was a bespoke airframe with a V-1650 Merlin that absolutely deserves its own writeup.) The FAI record at the time was 499.018mph, set by Red Baron (a heavily modified P-51) in 1979. FAI records must be beaten by 1% to be official, so the record would have to average 504mph to qualify. Rutan set the design goal at 527mph and got to work. The airframe was completed in a June 1989, but engine development was significantly behind schedule, and the aircraft didn’t fly until March 22, 1991. On August 21, 1989, Rare Bear averaged 528.329mph, taking the FAI record. (A record it still technically holds. The rules were changed to remove the 1% requirement, and the new record average was set on September 2, 2017 by Steve Hinton Jr in Voodoo at 531.53mph, with the fastest of four laps clocked at 554.69mph.) Bonus picture of Rare Bear in its superior paint scheme:  While the engines would run on gasoline for normal flight (pretty much all Reno aircraft fly from their home airports to Reno for the event which again, is metal as gently caress,) the engines in the Pond racer would burn methanol for competition. Running alky would allow for much cooler combustion temperatures, the evaporative cooling of the fuel would eliminate the need for an intercooler (and thus the drag penalty of an intercooler scoop,) eliminate the anti-detonation-injection systems required for competition on the other unlimiteds, and allow power settings as high as 1,000hp@8000rpm. In order to to get the aerodynamics required for 500+mph on ~2000hp, the engines had such loose engine clearances (typical for alky) and was so tightly cowled (26” overall cowling diameter) that the engines not only required preheating to nearly operating temperature before startup, but also post-run cooling in order to protect the structural integrity of the composite airframe. It was essentially an airborne F1 car.  The Pond racer had a shakedown race in the Unlimited Silver class in 1991, with the aircraft fresh out of test flight. They qualified at almost exactly 400mph, but DNFed due to a rapid unplanned engine disassembly and associated fire. For 1992, they decided to return to an unspecified (air racing is still a very suspicious bunch of people, and no one likes to talk about specifics) gasoline fuel blend (probably still with some methanol) and qualified at 358mph, finishing second at 364.978mph in the Unlimited Bronze race. Returning for ‘93, during a qualification run, the pilot of the Pond Racer told the tower he was leaving the race course with mechanical trouble with the #2 engine. The tower advised that he was trailing smoke. Observers on the ground reported a puff of smoke, followed by a smoke/oil trail, and that the starboard prop had stopped in the unfeathered position. Unable to make the runway with the added drag of the unfeathered prop, the pilot elected to attempt a gear-up landing, but overshot a clear area and came down in uneven terrain. After traveling ~900ft along the ground, the fire in the right nacelle intensified, consuming the right wing, nacelle, wing center section, and cockpit. Unfortunately Rick Brickert had apparently become incapacitated by the crash impact, as none of the emergency escape equipment (detcord around the canopy structure to separate it from the airframe) had been activated, and he perished in the post-crash fire. The NTSB found that probable oil starvation had caused failure of a connecting rod, which had windowed the block and started an oil/fuel fed fire. Sounds suspiciously similar to the DNF in ‘91. So there is the story of automotive technology failing in the air-racing world. Tsunami had crashed in 1991 killing its designer, and Pond declined to restart the Racer program. The challenge to warbird supremacy in air racing died with a whimper. Bonus picture of Tsunami:  Basically take the design ethos of the Gee Bee R-1 but use a Merlin instead of an R-1340. Why do I only effortpost in the mechanical failures thread? I don’t know. MrYenko fucked around with this message at 18:45 on Jan 25, 2022 |
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Jan 25, 2022 15:00
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stinch posted:I have a small diesel hatchback and it's quite noticeable in the handling how heavy the engine is. i guess that would make experimenting with diesel engine in a small aircraft a pretty substantial project. It's this. Power-to-weight ratio is the thing auto diesels are fighting against in airplanes. Even crappy aero engines are better than .6hp/lb. An IO-360 makes like 200hp and weighs 300lb. A Passat 1.9TDI makes, what, 100hp? And weighs shy of 400lb? Gonna need a bunch of boost and stuff to get the P:W down enough. *figures from wikipedia, picked the 1.9TDI because I could find a shipping weight for one.
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Jan 25, 2022 16:43
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BraveUlysses posted:sigh Is that a K24? 🤔 I'd also be down with the 'rtv and send it' approach
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Jan 25, 2022 17:25
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yeah k24 in a honda element yeah it will probably be ok with rtv i'm just annoyed about it
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Jan 25, 2022 17:30
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MrYenko posted:
i don;t know, but i'm glad you do. that's insane is gently caress, thanks for the post!
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Jan 25, 2022 17:55
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At just a glance I knew that was a Rutan thing. Surely you meant Burt Rutan though.
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Jan 25, 2022 18:30
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Wasabi the J posted:At just a glance I knew that was a Rutan thing. Fixed, I did. His brother Dick was project manager at scaled, and I was bouncing names around my brain parts.
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Jan 25, 2022 18:46
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Sagebrush posted:paul bertorelli is not just "some aeronautics guy," he's the best aviation youtuber there is. Omg I love this guy instantly, haha. I watch tons of aviation YT how did I miss this, thanks for the heads up!
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Jan 25, 2022 20:25
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Sagebrush posted:paul bertorelli is not just "some aeronautics guy," he's the best aviation youtuber there is. I love how the stripes just keep getting... more in the course of the video.
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Jan 25, 2022 21:11
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Well goddamn that was a hell of a story. He should try it again with all alloy block LS motors.
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Jan 25, 2022 21:13
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I found Paul recently from I think the OSHA thread. Really enjoy his videos.
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Jan 26, 2022 04:17
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