2008 Infiniti G35 X Sedan 4-door 3.5l on 2040-cars

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Submit your questions for Autoblog Podcast #344 LIVE!

We're set to record Autoblog Podcast #344 tonight, joined by Doug DeMuro, author of Plays With Cars, formerly of Porsche Cars North America, and all-around swell guy. You can drop us your questions and comments via our Q&A module below, and we'll give them extra-diligent attention. Subscribe to the Autoblog Podcast in iTunes if you haven't already done so, and if you want to take it all in live, tune in to our UStream (audio only) channel at 10:00 PM Eastern tonight.
Discussion Topics for Autoblog Podcast Episode #344
BRZ STI?

Infiniti Prototype 9 is a wonderfully beautiful EV grand prix car

Few automobiles are as elegantly beautiful as the open-wheel grand prix cars of the 1940s, '50s and '60s. The simple, slender shapes of these cars bear no extravagant flourishes or adornments. The purposeful design is what gave these cars their beauty, and it's these classic machines that inspired the new Infiniti Prototype 9. Teased earlier this week, this concept blends old and new, with classic lines hiding a modern all-electric powertrain. The Prototype 9 will make its full debut next week at the 2017 Pebble Beach Concours d'Elegance. Infiniti says the car was built around a simple idea: what would a 1940s Infiniti grand prix car look like? While the silver paint may be more German than Japanese, the design could easily be mistaken for an actual '40s grand prix car. Only the Infiniti-styled grille gives it away. Everything about it, from the thin bias-ply tires wrapped over center-locking wire wheels to the bulging screws around the driver's seat, is pitch perfect. Underneath that achingly long hood rests a prototype electric motor and battery from Nissan's Advanced Powertrain Department. The combo sends 148 horsepower and 236 pound-feet of torque straight to the rear wheels. That's good enough to send the svelte 1,962 lb car to 62 mph in just 5.5 seconds. Top speed is right at 106 mph. While speed may die off towards the top end, all that torque and a 43/57 front to rear weight distribution should make the Prototype 9 a riot on a small, tight circuit. There's only enough juice in the battery for about 20 minutes of flat-out racing. The handmade steel body rests on a steel ladder-frame chassis. The front suspension uses a leading-arm rigid axle with transverse leaf spring while the rear uses a De Dion axle, also with a transverse leaf spring. The Prototype 9 also uses old-school hydraulic rotary type dampers. There's no power steering and no brake booster for the four-wheel disc brakes. The car was designed and built by a number of different departments within Infiniti and Nissan. A simple sketch expanded as more and more designers and engineers wanted to have a hand in the project. The steel body panels were all shaped and hammered by hand. The bare cockpit is only adorned with a thin seat, three gauges, a few switches, a gear selector and the steering wheel. The gauges are set into a fixed aluminum hub in the center of the steering wheel.

Infiniti's new VC-T changes the rules of small turbocharged engines

The upcoming Infiniti QX50 crossover does not get our pulse racing, no matter how shapely the QX Sport Inspiration concept that previews it may be. No midsize SUV does, to be fair. But it has something special under the hood – the world's first production variable-compression-ratio engine. That means the QX50's 2.0-liter turbo four, which makes 268 horsepower and 288 pound-feet of torque, will have up to 27 percent better fuel economy. Here's how it works. The trend of moving to smaller, turbocharged engines carries with it one big falsehood. Under low load when the turbo isn't needed, these engines are less efficient than an equivalent engine without a turbo because of the low compression ratio the turbo requires. That is, if you never need the extra power, you're wasting fuel. Turbocharged (and supercharged) engines use a lower compression ratio to prevent detonation. When you force extra air in a cylinder and mix it with fuel, it's more likely to prematurely go boom. Lowering the compression ratio prevents this problem, but it's less efficient. Infiniti's VC-T promises the best of both worlds, with a compression ratio that ranges from 8.0:1 for high-power turbo needs to a 14.0:1 ratio for fuel-sipping efficiency. At its heart the VC-T engine is a simple idea, but it's complicated to explain. Consider yourself warned. The photo below from Infiniti serves as a good visual overview. For the truly nerdy, this patent application covers the mechanical concept. Instead of having the pistons connected to the crankshaft, Infiniti's engine has a pivot arm with a connection on each end. One end connects to the piston, the other connects to a second lower shaft, which is controlled by an actuator arm. At any given time the engine's pistons move up and down according to the lobes on the crankshaft. But the actuator arm can change the angle of the pivot arm up and down. That is, the pistons still move in the same motion with the same stroke, but phase the entire stroke up or down. Move the pivot up and there's less room at the top, which means a higher compression ratio. Move the pivot down and the compression ratio goes down, too. As an added bonus, the lower shaft eliminates the need for counter-rotating balance shafts. Infiniti says this system works constantly and can vary the compression ratio to any number between 8:1 and 14:1. It also uses electronic variable valve timing on the intake valves to switch into Atkinson-cycle combustion for greater efficiency.