dwightlooi

The Camry did... it was called the Solara. The Accord did, but not anymore. Generally, the people in the market for a stoic 4-door sedan is more interested in the practical side of transportation than losing two doors for cooler looks and/or a more youthful persona. 2-door versions of stoic 4-door sedans don't really sell. If GM wants to do another coupe, and they probably should since a Camaro with its muscle car appearance isn't exactly most people's cup of tea, do it as a separate model that has nothing to do with the Malibu. Do it on the Alpha like the 130R or the Detla like the 140S. Whatever you do, don't take two doors off of the soccer mum sedan. It doesn't work, it has never worked and it won't ever work.

All I can say for people for who bought a plug-in hybrid is that these cars do not make economic sense without the $7500 in federal tax credit and up to $6000 in state subsidies (eg. California) -- and sometimes not even then. That's $13,500 of hard earned tax payer dollars and/or increase in the national debt. If it works for you after the subsidies, well... good for you! But, bad for the tax payer, bad for me, bad for the economy and bad for energy independence. I have no problems with misguided "global warming" coolaid drinkers wanting to feel good about themselves and cut carbon emissions. But, I do have a problem with them doing it with my money.

Should never have wasted money and time developing the 2.0L FA20 boxer engine. The FR-S/BR-Z would have been better powered with the same engines that went into the Imprezza -- the 148 bhp FB20 and the 300 bhp EJ207.

The oldsmobile transmission (which I am not familiar with) looks like a transverse transmission with a 90 degree diffferential mounting in the engine's oil pan area. The will make a longitudinal engine layout in a FWD application less nose heavy by reducing powertrain weight which overhangs the front axle. However this is not the layout of any existing transmission and using this layout will require a new transmission design -- I was referring to using a V4 in a FWD application using existing transmissions. If you are to design a dedicated transmission, the more interesting thing to do -- from a balance standpoint -- is actually to take the conventional VW/Audi or Subaru style tranny and install it backwards. In otherwords, the engine is completely behind the front axle with the transmission sticking out the front. Mechanically, it is relatively easy to do since all you really need to change is the side differential input gear engages the output shaft (which reverses the direction of wheel rotation). This presents some challenges with regards to accessories serviceability since the pulleys, belts, AC compressor, water pump and alternator will be on the firewall side. But this isn't actually any worse than you see with mid engined cars and is something you can live with. Normally, such a layout will require that the front axle be pushed out away from the firewall or the engine won't fit. But, since we are dealing with a V4 the engine will actually fit within the extents of the wheel well so no such change is necessary. The transmission being in front may also intrude into traditional radiator spaces, but this can be accommodated by using a horizontal radiator and a vent channel in the hood (ala Corvette C6R).

The Fiero chassis was, should I say, overweight and flexy. The suspension on everything but the 88s also sucked dirt and steering always felt "lose" and imprecise. Brakes were horrendously weak by modern standards. Compared to the 1st generation MR2, the fiero sucked as a driver's car, although it did have a surprisingly larger and useful trunk (which forces you to look at that red painted 2800 V6 every time you use it). The "GT" body looked really nice though. I had both the 88 MR2 Supercharged (4A-GZE engine) and a 86 Fiero SE V6 (not the fastback GT). I very much prefer the MR2. Not that it doesn't have its flaws -- the intercooler installation right on top of the engine with a small fan drawing hot air from the exhaust manifold area is class 1 retarded -- but it is faster, more agile and significantly better handling. Having 5 speeds vs 4-speeds on the manual transmission helped too. Both cars weighed in the mid to upper-mid 2000 lbs range. Both didn't have power steering. Both seat you close to the floor with a tall central tunnel supporting your elbow. It's hard to find a car like that anymore - especially the low seating position which I loved and the under 2800 lbs weight which really makes for an interesting driving experience. I'll gladly pay 10K for a nice MR2 Supercharged if I can still find one. But they are pretty much gone from the market.

Actually, no. The Longitudinal FWD transaxles have the differential and output shafts located just behind the torque converter near the bell housing. This is generally inline with the front wheel hubs. It means that generally, the entire entire and usually a part of the transmission (namely the torque converter or clutch assembly) overhangs the front wheel axis.

Because a 90 deg V4 is very short, but wide. When you place it in a transverse setup, it requires much more engine bay length than an inline engine or a 60 degree V6. More importantly though, in a transverse arrangement it has no advantages over an inline-4. But why restrict to transverse setup? Ooo. Good question! It could use the same transmission layout as my Toronado or the Dodge Intrepid has. Because... (1) GM does not have a longitudinal FWD transmission (ala Audi or Subaru) in the Hydramatic lineup (2) GM FWD Platforms are not designed to take that configuration. (3) Longitudinal FWD in general is a bad idea from a balance standpoint because it has worse balance than a transverse FWD layout and while having the same footwell intrusion that RWD setups suffer from.

Because a 90 deg V4 is very short, but wide. When you place it in a transverse setup, it requires much more engine bay length than an inline engine or a 60 degree V6. More importantly though, in a transverse arrangement it has no advantages over an inline-4.

If GM wants to redo a four cylinder for FWD applications, it'll be more worthwhile to look at going to a SOHC 2-valve head with an Atkinson cam grind, cam-in-cam VVT and 14~15:1 compression ratio using direct injection. In doing so, you trade specific output for fuel economy. A naturally aspirated 2.5L so designed has the best chance in beating the MPG numbers of the 1.4T and competing 1.8 and 2.0L engines in FWD compact cars like the Cruze. Output will be ~160 hp which is better than the 1.8L DOHC or 1.4T as currently tuned, and about par with the Focus, Mazda 3 and other 2.0L cars. Basically, this is Skyactiv taken a step further with an increase in displacement, reduction in valve train friction and deeper intake regurgitation. For applications currently using the 2.5L DOHC four, a turbocharged version of such an engine (aka a Miller Cycle variant) will easily beat the 2.5L DOHC in fuel economy while offering similar performance at 200 hp. For Hybrids, they can chop that 2.5L Atkinson four down to three cylinders to 1.8L. This will offer the lowest parasitic drag compared to anything on the market while tendering about 120 hp (exactly where the output needs to be). Another thing they can look at is eliminating the torque converter and/or clutch entirely in mild hybrids. The idea is simple. A converter and/or clutch is really only necessary in automatics for idling and creeping at parking lot speeds. If you remove the need for a car to idle you remove the need for a torque converter or clutch. In a mild hybrid, a 10~20hp / 80~120 lb-ft electric motor can be used to always propel the car from rest. Once below 600 rpm in 1st gear the engine uses AFM to shut off all valves and stops injecting fuel. Idle stop is mandatory and electric propulsion is a given from rest. At 5 mph the engine can decide if it needs to cut in for more power.

All the narrow angle Vee engines (VR engines) have intakes on one side and exhaust on another. Basically, the intake ports and exhaust ports look like an Inline engine. You'll use just two cams with valve stems of different length allowing one cam to operate all the intake valves and the other all the exhaust valves. The downside is that the block has nothing to do with a V8 block as it'll need 5 main bearings and the combustion chamber will be completely different in geometry. In fact, all the VR motors have piston decks that are NOT perpendicular to the bore. All this means development costs will be like doing a completely new engine architecture. The key point here is that GM does not really need a "new" 4-cylinder that can be used in FWD applications. It already has the 1.4, 1.6, 1.8, 2.0T and 2.5 engines. A FWD application does not benefit from a reduction in engine length since the engine compartment is wide enough as it is to accommodate an Inline-4. On the other hand, GM can develop a unique large displacement four for RWD applications for very little money which allows the entire package to out perform and look substantially different what is possible by simply using Ecotec fours. In the same vein, Toyota ans Subaru chose to do a 200 hp flat four instead of using an inline four or an existing turbocharged flat four -- and they make excellent examples of both -- for the FT86 because neither would have fulfill the new car's packaging requirements, driving characteristics or weight targets. Desire is one thing, but their ability to do this affordably for a relatively low volume car and a singular application is based on sharing the architecture will the existing Subaru flat fours.

All else being constant, a 90 deg V4 is as tall as an inline-4 tilted over at 45 degrees. However, all else is not equal. The proposed engine is a pushrod design whereas the Ecotecs are DOHC mills. DOHC engine have taller, wider and heavier heads. Another problem with tilting an inline engine over is that you bias the weight towards one side since you have to rotate the engine along the axis of the crank shaft and cannot really move that sideways and still keep the drive shaft on the center line. In any case, the key advantage of the 90 deg V4 is that it is just a tad over 2 cylinders long and it is nowhere near as wide as horizontally opposed fours. These allows the most compact packaging in a longitudinal rear drive application. Being a pushrod design also allows you to exploit this configuration without increasing the number of camshafts and drive sprockets over an inline layout. If you supercharge it, the blower goes neatly in the valley of the engine, something you will find difficult with 60 Vees and impossible with VR4s (15 degree staggered fours). The downside being that a 90 deg V4 design based on a V8 architecture has only two crank journals and you cannot have an even fire engine. This is OK, even attractive -- in the same manner that Ducatis & Harleys are attractive in their own right from their off beat exhaust notes -- in a sporty car or light truck, but is not ideal for a luxury car.

It's really not that complicated... If you have a four cylinder engine and you remove the front and rear cylinders such that it becomes a 2 cylinder engine, does the center of gravity change? No, it doesn't. However, the nose can be shortened by about the length of one cylinder and the transmission is moved forward by amout one cylinder. Simple? That same goes for when you chop a V8 into a V4. A Smallblock V8 is about 23~24 inches long not counting the accessories. Chop it in two and you save about a foot in overall engine length. Half of that goes towards moving the firewall and transmission forward. The other half goes towards shortening the nose.

That is exactly why you want a very short engine. The transmission is widest at the bell housing. Keeping the center of gravity of the engine where it is, if the engine is very short, half the the reduction in length goes towards moving the transmission FORWARD which widens your foot well space. The V4 is basically a foot shorter than the V8 or an I4. Half of that, about 6 inches, goes towards moving the entire firewall forward giving additional foot well width and depth. The other way of course is to move the transmission to the back and use a rear mounted transaxle.The problem with that is that for most cars the height of the rear bench and or the width between the rear seats are simply not suffcient for that. In a vette this is not a problem because you have no rear seats and an elevated rear platform, but this isn't so four most 2+3 or 2+2 configurations. Another bad thing about a rear mounted transaxle is that you need to carry your engine torque to it with a fast spinning torque tube going the length of the central tunnel. This, like a heavy flywheel, reduces the rev response of your engine. Not much of an issue for a 465lb-ft V8, but in a smaller engine that needle will rise and fall at a slower rate affecting performance and driving experience.

Just look at the illustration above! To each his own tastes when it comes to aesthetics, but those proportions will not be possible with an inline four. It is also not purely a "styling" issue but a functional one. A car's wheelbase has a lot to do with it's weight since the wheels are the carriers of the entire load. All the structures between the wheels give the car it's torsional and bending strength. With the same rigidity and strength requirements, the shorter the wheelbase the lighter the car. That ~10% reduction in wheel base is responsible for most of the weight loss. But a short wheelbase also means less leg room for the occupants in the passenger cell. A V4 engine -- being 2 1/4 cylinders long -- allow you to move the firewall forward towards the front axle. This allows you to make this a 2+2 vehicle with tight but usable rear seats. If you don't use a V4 the car will have to have more wheelbase (be heavier) or you need to lose the rear seats. From a structural standpoint, the "strongest" design for a unibody is to have the a-pillars terminate at the front strut towers. This is generally impossible in practical cars because of the length of the engine and the desire to have good F/R weight balance. Move the axle further from the firewall and the structure weakens, requiring either weighty reinforcements & bracings, or a sacrifice in platform rigidity and suspension performance. The V4 gets you closest to the ideal triangulation of forces.

I think a point of clarification is in order -- developing a brand new engine architecture is expensive and producing it is even more so because of the need to start an entirely new logistics chain. Developing a variant and/or producing it is generally not. For example, when GM didn't have the a DOHC 16v engine developing the "Quad 4" was a big deal. I also didn't go that smoothly in the beginning. However, GM has no issue producing the LS7 V8 which was used in a very limited number of even fewer models -- namely the Corvette Z06 and now that this is being phased out the Camaro Z28. They also had no issues doing a 2.0L version of the 2.2 Liter Ecotec fortified with an Eaton M62 supercharger specifically for a few thousand copies of the 1st gen Cobalt SS. Or, does anyone remember, the 4-cylinder 2.8 and 2.9 liter Inline-4s which were cut down versions of the "Atlas" DOHC Inline-6 (LL8) which were used only in Chevy Colorado and GMC Canyon (which accounts from less than 1 in 20 trucks or SUV that GM sold. The V4 was proposed because it can do what an Inline-4 or Flat-4 turbo cannot. It allows the interior space to be about 6 inches longer with the same wheelbase by allowing the engine compartment to be really, really short. It fits where a flat four of similar displacement won't because of width. It fits a supercharger in the valley of the block in a way that an inline or even 60 deg V engine cannot. It offers about 300hp from 3.1L which at a mild 9 psi of boost, yet exceeds the power level of a 22 psi 2.0T at a similar weight with no turbo lag. It would not have been economical had the LT1 not existed and GM relies on a line of DOHC V8s just like everyone else. But GM has the smallblock card to play that no one else does. It is a application specific engine with very little application outside a compact front engine / rear drive vehicle, but the same can be said of the 2.0 4U-GSE Flat-4 in the FT86 (FR-S / BR-Z). In fact, if you optimize it for regular gas it may make a decent entry level truck engine if GM is interested in making mid-size pickups again. Otherwise, it'll be a limited volume engine like the LS7, LK5, LLV and LSJ, which is fine.

How so? The V4 has a packaging advantage which cannot be matched by Inline-4 designs or horizontally opposed -- it is how that extremely short hood and chassis is possible. A 90 deg Vee has each pair of cylinders exhibiting the same great balance as a V8 by allowing full counter weights to be used. A Pushrod V4 has a mass, width, height and frictional advantage unmatched by OHC designs. Those are fundamental facts. Why do you think it won't work out? As far as it not actually being an existing engine, well neither is anything GM hasn't built yet (including the car itself). By that line of reasoning -- if doesn't exist it is impractical -- nothing new would ever be built.

There is a reason the V4 has a VFR firing order instead of being even fire. The latter would have required a 5 main bearing block, whereas the proposed design is strictly a chopped LT1 leaving three main bearings. Doing this avoids the vast majority of costs associated with developing a new engine. Basically the combustion modeling is identical to the LT1 and does not have to be redone. The pistons, rods, bearings, wrist pins, sprockets, pushrods, lifters, rockers, valves, bolts, coil packs, fuel injectors, fuel pump, water pump, timing chain... basically everything but the block casting and shortened camshaft is identical. Even the block casting is basically a straight forward modification of the V8 block eliminating the center four cylinders. Tooling and production machinery for its assembly is also interchangeable. In fact, doing such an engine is somewhat less work and investment than doing a 5.3 liter version of the Gen V V8 or going from a 2.5 to a 2.0T -- because you are not changing the combustion chamber geometry and do not have to redo the combustion modeling.

Equipment and Amenities The interior is spartan but not low rent. Navigation is standard, but climate control is manual, seat adjustments and mirror adjustments are manual. The heats are not heated or cooled. A backup camera is standard, but sonar parking sensors and/or dipping side mirrors are not offered. The 240W BOSE audio system offers AM/FM/Sirius radio but does not accept CDs or cassettes, offering instead iPod and USB integration. Featuring just 3-speakers – a pair of 2.5” full range speakers in the A-pillars and an 8” bass/sub-bass driver in the center dash deck – it is similar to the basic Acoustimass 3 setup for rooms. Not exactly Hi-Fi, but lively, distortion free and entertaining. Leather is not offered, but the cloth is of three different textures and the dash and doors are fabric wrapped. Switches and rotary controls have rubberized diamond knurl grip surfaces, are positively indexed and solidly damped. The steering wheel is a 3-spoke design evolved from the Corvette with paddle shifters fitted on the automatic transmission equipped cars. The instrument cluster is elemental – an analog tachometer on the left and speedometer on the right, with a concentric LED fuel gauge inside the speedometer and (on supercharged cars) a concentric LED boost gauge inside the tachometer. Apart from that, the only display in the cluster is a multifunction LCD in the middle which can pull various duties such as trip computer, voltage/oil-pressure/oil-temp/water-temp and warning messages. Regardless of mode, the MFD displays the current gear on the top right corner in a circle. On the automatic transmission cars, a smaller letter on the lower right corner of the circle indicates the current drive mode (P-R-N-D-S-M).

Chevrolet Speed - Sports Car for the People A Simple Formula 300 hp 3,000 lbs 30,000 Dollars The idea is not to build the best sports car in the world. It is to build the best sports car that the 20~40 demographic can actually afford. It is not the most powerful. It is not the lightest. And it is not the cheapest. But, it is powerful enough to equal a Boxster S at the stop light, it is light enough to approach the FT86 in driving dynamics and, most importantly, it is cheap enough to that a regular college grad can afford one. It is from this car that GM will graduate future Corvette and Cadillac-V owners. Design & Platform The Speed is heavily influenced by the Code 130R, but substantially different in most ways. It is not built on a standard Alpha Platform, but a heavily modified version called the Alpha SLC - Short Light Coupe. The wheelbase is shorten by 9.8 inches to 99.5 inches. Height is reduced by 3.8 inches to 52.1 inches. The belt line is dropped by 2.5 inches and the car is a full 23.1 inches shorter in length than the Cadillac ATS. Unlike the Alpha which is engineered to accommodate a wide variety of vehicle configurations and engine types, the Alpha SLC is tailor made for use strictly in 2+2 hardtop coupes powered by a Smallblock V4 engine. In fact, the engine compartment is so short, and the firewall is so far forward, that not even GM's upcoming 3-cylinder Ecotec will fit. Apart from the physical dimensions, the green house has a lot more rake and the nose is a lot shorter. It is almost difficult to imagine this as a RWD vehicle due the exceptionally short hood, but it is -- thanks to the V4 engine. Most importantly, the dramatic reduction in it's load carrying extents (mainly the wheelbase) and enveloped volume allows the vehicle to be approximately 400 pounds lighter than an ATS (300 lbs if you discount the disparity in equipment level and sound insulation). The Specifications Powertrain The design objective calls for maximum power output from the lightest, most compact engine. To this end, a 90 degree V4 engine that is basically a LT1 Smallblock V8 chopped in half is employed. Displacing 3.1L (188 cubic inches), the direct injected pushrod engine is about the same weight as a 2.5 liter DOHC Inline-4, but is only 2¼ cylinders long and significantly lower in height. The engine has two crank pins spaced 360 degrees apart and is supported by three main bearings. It exhibits the good overall balance of a 90 degrees full counter weighted engine, but is not an even fire design. With the crank pins spaced 360 degrees apart, the engine fires twice in 90 degrees of rotation then pauses for 270 degrees before firing twice again. This gives it a characteristically staccato exhaust note (1-1-0-0-1-1-0-0) at idle which turns into a guttural bellow when revved. The engine sounds almost like a Honda VFR750 motorcycle which has the same firing order. Synchronous cam phasing is used as on the Corvette V8 (LT1), but Active Fuel Management (Cylinder Deactivation) is not fitted owing to the impracticality of running the engine on just two cylinders. Direct Injection is employed using a combustion system identical to that on the LT1 V8. The engine offered in naturally aspirated form with 230 bhp @ 6000 rpm with 230 lb-ft @ 4600 rpm, or fortified with an Eaton TVS R1050 (1.05L) supercharger good for 300 bhp @ 6000 rpm with 300 lb-ft @ 3600 rpm. Eschewing the high costs of an 8-speed automatic or dual clutched manumatics, the transmission choices are relatively traditional. Both the base vehicle and the SS are available with either the GM Hydramatic 6L45 automatic or a Tremec 3160 manual -- both offering 6-speeds and automated rev matching. An electronically controlled active rear differential is optional on the base car, standard on the SS. Stability control is standard on both but launch control is featured only on the SS. Suspension, Brakes & Tires Suspension geometry is identical to the Cadillac ATS -- strut fronts, multi-link rears. Magnetorheological shocks are not offered to keep costs down and the Speed relies on traditional coil springs, tube shocks and anti-roll bars to keep vehicular motions under control. Brakes are lifted straight from the ATS with 11.8 x 1.0 inch front rotors on the base car and 12.6 x 1.2 inches on the SS. Both trims get 12.4 x 0.8 inch vented rears. The SS also gets Brembo floating calipers. Rubber on both trim levels are 225/45 R17 with alloy wheels. The base car is fitted with Goodyear Eagle GT All seasons while the SS gets Eagle F1 Asymmetric 2 Maximum Performance summer tires. The Competition

When you make 300 hp without having to run high boost + low compression, and when you move the same amount of air needed to make that 300hp by turning over at half the speed, your fuel economy is better. 300hp is from a air pump that moves at at roughly the same rate as the engine ingests it -- ie. very little boost just enough to overcome the residual pressure of the exhaust gases. Basically you are getting 3.6 liter NA V6 class output from a 2.0L with high compression and near atmospheric aspiration. If you feed it with 22~23 psi of boost like the 272hp 2.0T (LTG) does, you are looking at about 500 hp.

I hope they drop the 1.4T and 1.8 NA in favor of three gasoline engines of 2.0L displacement. BASE -- 2.0L DOHC 16v Normally Aspirated DI-VVT -- 160 bhp @ 6300 rpm / 150 lb-ft @ 4300 rpm ECO -- 2.0L DOHC 16v Turbocharged (Miller Cycle) -- 175 bhp @ 4600 rpm / 200 lb-ft @ 1600~4600 rpm SS -- 2.0L DOHC 16v Turbocharged -- 270 bhp @ 5600 rpm / 260 lb-ft @ 1800~5200 rpm

This may be easier than you think... especially if it's just a scaled mockup for show and tell. Go model it in Solid Works, Creo or Catia. Save the model as a .STL file. Give it to a 3D printing shop and have it printed on some 3D printer of your preference -- SLA, SLS, FDM or Polyjet. It'll cost a few hundred bucks. You can print the block and heads in clear plastic with the internals in a solid color. You can then assemble it, turn the crank and have everything move. It's a one weekend project really.

Theoretically about double the power density of a 4-stroke and twice the impulses per cylinder (a 3-cylinner will fire with the same frequency as a V6)

A 2-stroke engine -- by definition -- is one which fires once every time the piston goes down and up -- hence 2 "strokes". A 4-stroke is one which fires once every time the piston goes down and up twice -- hence four strokes. Most two stroke engines have ports, whereas four strokers have valves. But this is not strictly speaking true. You CAN -- as in the SPOHV design -- have a 2-stroke engine that has valves, or in the case of a more conventional design with overhead intake and exhaust valves which operate at twice the frequency as a 4-stroke engine. Valves which we are used to are called poppet valves, but they don't have to be poppet valves. In fact, prior to and during WWII, a popular design choice is the use of "sleeve valves". Sleeve valve engines have ports on the side, no camshafts, no springs and look like 2-stroke engines. BUT, the intake and exhaust ports are covered and uncovered in succession by a rotating sleeve around each cylinder. The Bistrol Hercules(14-cylinder Radial) on the Beaufighter and Napier-Sabre (inline H-24 cylinder) in the Hawker Typhoon are widely used sleeve valve engines.

Mostly, just the extra phaser and the fact that the cam itself will weigh as much as a regular camshaft which is NOT gun drilled or hollow cast for weight reduction. Many are not anyway.