dwightlooi

Except it was a STUPID DESIGN which defeats the purpose of having disc brakes. The early Chrysler disc brakes works very much like a drum brake. The pads and caliper is on the INSIDE of the bloody thing. Instead of clamping down on an exposed disc, it pushes out on the brake housing. The only difference between it and a drum brake is that the pads pushes laterally rather than circumferentially. The two principal advantage of a disc brake -- a larger working surface for a given unsprung weight as well as superior cooling and dust ejection -- is not realized because the entire caliper assembly must be contained within the cast iron housing and it is all enclosed.

It's longitudinally engined, full time AWD... aka Quattro. The entire engine is ahead of the front axle. The transmission and the front differential axle is in a single casing. The center and front differential are torsen type limited slip; the rear differential is active. The default torque split is 40 front / 60 rear, but out to 85% can go to the rear and 65% can go to the front. -- It is also a Hot Vee engine. Meaning the exhaust comes out in the middle and the twin turbos sit on top in the valley of the Vee. The intakes are on the sides. There is an air-to-water aftercooler in the front between the throttle body and the intake plenums. The turbos are tiny and design for response not maximizing engine power. The engine makes a paltry 435 hp @ 5,100-6000 rpm with 444 lb-ft available from 1,500-5,000 rpm. The redline is a modest 6,000 rpm.

I defected back to the Germans this Christmas... got myself an Audi A8L 4.0T. The car sold new for 109. But at 4 years and 40K miles as a Certified Pre-Owned, it is $31.6K making it an exceptional value. This is in part due to the SUV craze and in part due to the fact that car enthusiasts are generally gravitate to the S-cars, the M-cars, the V-cars and the AMGs. This left the traditional flagship sedan with low demand and fantastically bad residual values (71% depreciation in 4 years). It is no S8 Plus for sure, but it is brisk enough.

Good for you! Just don't look back and say I could have gotten this or that a year ago and make out like a bandit. You don;t need to go that far back, Just go back a week and you could have bought the winning Powerball ticket!

LOL... you could have bought AMD @ $2 in 2016 and it's $40 today. Put a million down on that instead of a home and it'll be worth 20 million today. Moral of the story? NEVER look back and moan over the investment you should have made. That's a sure way to be very unhappy.

They dropped the Volt because nobody is buying them and they are losing money on every single one. The idea is very simple. Electric Power from the battery only needs to get you to work and back or from the shopping mall and back. That's 30-60 miles round trip for most people. That's 90% of the driving. Everything else is the exception. Fuel Economy doesn't really matter for the exception. It is more important that it be convenient, tiny, light and cheap. A turbocharger is about $600~700 if YOU buy one. I am pretty sure GM is not paying $600-700 to KKK, Honeywell or Mitsubishi when they buy them in the tens of thousands. A two stage turbine generator is basically two small turbos, one combustor can and a starter generator. There is no coolant, no radiator, no cams, no valves, no lifters, nothing. In aviation engines they BURN the oil and simply top it off as an expendable. If you want to recycle that you'll have an oil cooler, but that's about it. It is totally conceivable that the entire ensemble be under $2000 even in moderate quantities and with today's technology.

Let me put it in a simple way for everyone to understand. The problem with electric cars is that the energy density of batteries is horrible. A battery that gets you 300 miles is over 1000 lbs -- closer to 2000 if you count the structure you need around it not just the cells. 10 gallons of gasoline takes you 300 miles in a 30 mpg car and it weighs 60 pounds (the tank weighs less than the fuel) The way to solve the problem is to make the battery as small as possible and use it as a buffer rather than an energy source. You then replenish it with the smallest and lightest device that can convert hydrocarbon fuel to electric charge. Now picture a turbocharger a small car like the CLA45 AMG. That'll flow enough air to make about 400hp and raise the pressure about 3:1. If you take two of those you can raise the pressure about 9:1 and make 400hp without the pistons. If you only need 40 hp, imagine the turbos being 1/10th the size of the CLA45 turbo. Think two little pill bottles!

The powertrain is no different from the current "performance" electric powertrains like that on the Teslas or the Taycan. The ONLY difference is a turbine generator and we are throwing out 80% of that 2000 pound battery. The reason you go this route is that going from 20 kWh to 100 kWh (60 mile to 300 mile range) will cost you 1600 pounds. That turbine generator is about 50 pounds; 120 pounds with 10 gallons of gas. It is also about $3000 vs about $30000 for the extra battery capacity. The key here is that modern turboshaft engines are about 4 hp per (engine) pound. A 40 hp engine will only be 10 lbs. I am budgeting 5 times that because we want a CHEAP engine based on turbocharger technology not million dollar aviation engines., plus I am throwing in a generator.

The solution is simple. A SMALL BATTERY of about 10-20 kWh (30-60 mile range) capable of high current draws. A micro gas turbine generator making about 30 kW (40 hp) capabe of recharging the battery in 20-40 mins with the car stationary or about twice that when it is cruising along gently on the freeway. Who cares if the turbine is fuel efficient? It is only used when you are on a long trip or to "recover" from a stint of very aggressive driving. The important thing is that the turbine is very small, does not need coolant and is essentially maintenance free between time to overhaul. It'll fit in the spare tire well! The simplest practical design is a 2-stage centrifugal unit that looks like two sequential turbos with a combustor can between the compressor and the turbine, as well as a high speed AC generator on the shaft of the low pressure compressor. It should cost about as much as two turbos and an electric motor. Two centrifugal stages is good for about compressor pressure ratio 10:1~12:1 compression ratio (3.3 x 3.3 to 4 x 4) -- about the same as a modern piston engine. It is no GEnx, but it's good enough. This also ensures that emissions will be about the same as a typical gasoline piston engine. Unlike a Hybrid's ICE, the turbine either operates at optimal speed or not at all. When starting the generator-motor spins the low pressure compressor to about 150,000 rpm and generates a combustor inlet pressure ratio of about 3~4:1 which should be enough for the unit to be self sustaining. Fuel combustion and will spin up the high pressure turbine to speed and bring it to the operating pressure ratio. Start up should take about a minute. The Driver as a three position switch for the turbine generator -- OFF, ON or AUTO. OFF is pure electric. ON runs the turbine as long as the battery is not full. Auto runs the turbine when the battery drops below 20% (6~12 mile range). Very simple.

Actually, it does. Not a heck of a lot, but noticeably more than very low boost Germans like he Audi 4.0T. The reason is simple. It takes longer to get to 640 lb-ft than it does to 444 lb-ft. That boost rise simply takes longer. The Germans have very tiny turbos reaching only 122 lb-ft per liter vs 152. Boost only reaches 9.5 psi and plateaus from 1,500 to 5,100 rpm. Anyway, the whole hand built and exclusive to Cadillac thing is bullcrap. You can handbuilt and make exclusive a version of the small block V8 too.

I drove it last week, albeit not crazy hard. It's smooth and quiet with minimal lag. Still, I must say that there is a little more "rubber band" effect than say the VW-Audi CEUC 4.0TFSI. That might be because that engine peaks lower and with less toque (443 lb-ft @ 1,500 rpm) and doesn't make as mcuh power 435 hp @ 5,500 rpm. Less boost means less boost rise and a more linear perceived power delivery. I still think that trying to be more European is a mistake for Cadillac and GM. There is no need to do that. I'll very much prefer that Cadillac stuff their flagships with a "Premium" Pushrod V8 given the features which Chevy had to cut out from the LT2 for cost reasons. Features like individual throttles, Dual Injection and concentric cam dual VVT. A 6.8L V8 with all these features and the LS7 stroke will produce an estimated 550 bhp @ 6,200 rpm with 525 lb-ft @ 5,200 rpm. No turbos, no intercoolers, no lag, no extra weight and no extra things to break. With AFM it'll still turn in 16/25 mpg which is good enough and no worse than the LTA 4.2TT. I'll also get rid of ALL the 3.6L V6es altogether. Full size Sedan and SUV Caddy customers can have a choice between the 2.7L Turbofour or the big V8 depending on their preferences for economy or performance. There is no reason for the 310-335 hp V6 to exist. Crossover and compact customers can choose between the 2.0T and the 2.7T. Very simple power train lineup. Maybe they can upgrade the 2.0T and 2.7L to a "premium" setup exclusive to Caddies and Buicks -- Air-to-water intercooling, individual throttle butterflies and dual injection. The 2.0T should easily make 280-300 hp and the 2.7T 380~420 hp with NO CHANGE to compression ratio and boost pressure (by not running out of breathe at 4,500 rpm).

They can. Google GM Duramax 6.6 turbodiesel (L5P) -- that's pushrods, 4-valves and 910 ft-lbs @ 1,600 rpm. Also, most of the Honda Civic engines in the 1990s and 2000s were SOHC 4-valve designs -- Google Honda D16/D17. Even today, the 3.5V6 in the Pilot, Odyssey and (Acura) MDX is a SOHC 4-valve design -- Google Hona J35.

Raining like hell here in the SF Bay Area. 56 deg F. Well, at least the turbos are making more power. Cool and humid is good. That's like denser air and water injection. Besides, the Pilot Sport 4S is actually pretty good in the rain (surprisingly).

Cadillac is lost on styling. Their new stuff looks "Mazda Inspired". But, they have also shown a lot of inconsistencies and indecision, hence who knows if the next vehicle will go back to the previous gen cues, stay the course or go in a totally new direction.

Thanks!

(1) Valve and spark arrangement in modern Hemi pushrod cylinder head. (2) Flat Deck 6.6 Duramax turbo-diesel pushrod cylinder head. (3) Rocker and bridge arrangement on 6.6 Duramax turbo-diesel engine (4) Junkers-Jumo 213A engine showing off -- Direct Injection, Twin Spark, 2-intake / 1-exhaust valves per cylinder and a variable drive ratio supercharger (hydraulically coupled)

Splayed or not, one rocket actuating one valve is no problem regardless of how the valves are oriented. But if you use a bridge to open both valves, they have to be parallel and the rod/rocket has to be perpendicular to the bridge. Otherwise as the rocker depresses it'll skew to one side of the bridge and open one valve more than the other -- like stepping on one side of a see-saw. The Hemi head is generally taken to mean ANY two valve head design where the intake valve is on one side and the exhaust valve is on the other side. This is irrespective of whether the roof is actually a dome or more of an oval. All the modern ones are oval allowing the flat decks on the sides to form a squish deck with the top of the piston to allow higher compression ratios. Twin sparks are very common with two valve and three valve designs -- OHC or Pushrod. If you want a REALLY HISTORIC example, go Google Junkers-Jumo 213A. That is a Supercharged 35 liter SOHC 36v inverted V12 cylinder engine used in the late WWII Focke-Wulf 190-D9 fighter -- it features three valves per cylinder, twin sparks and Bosch Direct Gasoline injection to generate 1,750hp @ 3,250 rpm (2,100 hp with 50% Methanol-Water injection in emergencies).

Actually, no. Not really. You cannot have four push rods per cylinder and still have room for the intake runner to reach both intake valves. The Chrysler Hemi design simply allow for the intake and exhaust valves to be opposed instead of side-by-side. The purpose of that being the theory that two opposed valves and a hemispherical combustion chamber is more knock resistant and hence capable of higher compression and output than the heart shaped combustion chamber with side-by-side valves. However, with the current generation of Hemi vs non-Hemi V8 engines, this theory does not seem to yield real world performance superiority.

Simple Answer: Yes it CAN. The Duramax 6.6 Turbodiesel in the current generation and previous generations are a Pushrod 32-valve V8. Complex Answer: The push-rods go from a cam in the valley of the vee to the inner side of the cylinder heads. These obstruct where the intake passages in an OHC engine would normally be. The intake passages hence goes around the pushrods offset to the right or left of the cylinders in the space not obstructed by the rods (and their channels). There is barely enough space to serve ONE intake valve per cylinder. If you put four pushrods in an engine you'll obstruct all the approaches to the cylinder from the intake side! Doesn't do you any good to have increased valve areas if you squeeze out the intake ports and runners does it? So how does the diesel 6.6 do it? Well, it still has two rods per cylinder. Each operate two tandem valves using a bridge between the valves. The inner and out valves on the left are both intake and the inner and outer valves on the right are both exhaust. This is possible because the roof of the head is flat and all the valve stems are parallel, allow one rocker to open both valves via the bridge. It is meaningful because it is a DIESEL engine and it doesn't rev past the mid-3000 rpms anyway so one single intake and one sn=ingle exhaust passage is enough to not be the airflow bottleneck. Had it been a pentroof combustion chamber like that found on gasoline engines, the bridge design would be impossible and having a single passage serve two valves would have defeated the intent of using more valves to increase the airflow potential at high rpms.

NO whistle

The thing is that you can have a Hybrid with 30~50 mile electric range (12~20kWH battery) or you can have a pure electric with 200~300 mile range. They'll weigh about the same. That additional 60kWH in battery capacity is going to cost you about 700 lbs in vehicle weight. If you'll like an ICE it is going to cost you about 700 lbs too for the engine, cooling system and transmission. If you want both, be prepared for a 5,500~6,000 lbs car (The model S is already 4,900 lbs).

Tesla quality -- interior wise -- has NEVER been at the level of a luxury car much less a $100K luxury car. In fact, Hyundai puts them to same.

Type S = Type SUCK Extra money for a lousier ride in a car that goes no faster.

LOL... a great American... uh... Canadian... novel worth of posts later it comes down to this. Oldhurst442 lives in Canada and is worried about corrosion in used cars. Because of import laws, he doesn't have access to cars from south of the border. Doesn't change the fact that a certified 3 year old will have ZERO CORROSION and ZERO ACCIDENTS or it could not have been certified. BTW, I am sure canada has no restrictions of Quebec folks buying cars from British Columbia.

There is this thing called SHIPPING. It costs $400~600 to ship a car to Northern CA from Southern CA, AZ or NV. About $800~1000 to ship it from the mid-west including Texas. About $1300 from the east coast including Florida. The last two cars I bought, I bought online sight unseen and have them shipped. With the exhorbitant rent and labor costs, buying from local dealers adds about $3000~6000 to the price of a $40K used car. So I buy out of state and pay a few hundred bucks to get it shipped in. If you are so fussy about salt and snow you can get yours remotely too.