Jump to content
Forums Gone... but not forgotten!
Pontiac of the Month

4 bucket 67's 1967 GTO

2019 March
of the Month

  • Welcome to Forever Pontiac

    We are a community of Pontiac enthusiasts. The purpose of our community is to keep alive the Pontiac spirit by sharing (or showing off) our cars, discussing Pontiac, helping each other work on our cars and find information, plus attend various meets/shows/etc... To aid discussion, sharing, event planning and selling of parts/cars/anything, we have various parts of the website to aid this from Forums to an online Garage to Classifieds to even a Document Download Repository. You can find links to these in our navigation above based on what each section helps with (discussion, local events, learning, etc...).

    We invite you to contribute, find help or just view some of our member's amazing cars! Don't forget, we also have great contests from time to time (like our Pontiac of the Month and yearly calendar contest) and our Pontiac This OR That, a fun game where you choose the best of two randomly selected Pontiacs from our online garage.

    We look forward to seeing you around!

Archived

This topic is now archived and is closed to further replies.

FeedBot

Car and Driver: Time Is Running Out for Bentley’s 6.75-Liter V-8, But Not in a Hurry

Recommended Posts

2015 Bentley Mulsanne Speed twin-turbocharged 6.75-liter V-8 engineWith torque characteristics and a soundtrack reminiscent of an ocean liner’s steam engine, the Bentley Mulsanne’s venerable 6.8-liter V-8 is a one-of-a-kind powerplant. But the 57-year-old engine, which the company calls a “6 3/4 Litre,” won’t survive beyond the current Mulsanne, we are told by Bentley CEO Wolfgang Dürheimer, who says that the V-8 has found its “final home” there. He confirmed that the next generation of Bentley’s flagship will be powered by a 12-cylinder engine, but he didn’t pin down a timeline for that car’s introduction.

-

If Bentley seems to be in no hurry to shed this key attribute of its heritage, it has also been clear for years that one of the industry’s most enduring powerplants couldn’t last much longer; now time seems to be ticking down to the end. Known as the L-series, the V-8 was launched in 1959 and subsequently used by generations of Rolls-Royce and Bentley models. It appeared that BMW had finally killed it off in the late 1990s, when it replaced the engine with a BMW-derived 4.4-liter V-8. At the time, Munich was already asserting that it wasn’t worth updating what was then a 40-year-old design to meet ever-stiffening regulations for emissions and fuel economy. But just a year later, VW took over and humbled BMW by reintroducing the L-series engine under the Red Label moniker. The BMW engine, christened Green Label, sold so poorly that it was discarded shortly thereafter. (It wasn’t good enough for BMW-owned Rolls-Royce, either, where V-12s now power everything.)

-

Mulsanne Speed V-8 NewsThe big powerplant, like the Chevy small-block V-8 that traces its origins four years farther into the past, has undergone significant re-engineering along the way. The bore center spacing is the same as on the original dual-carburetor 6.2-liter version that launched in the 1959 Bentley S2 and Rolls Royce Silver Cloud II, but the block (always aluminum) has undergone redesigns to stiffen the bottom end, the pushrod valvetrain now employs cam phasing to vary the timing of the pushrod-operated valves, there’s cylinder deactivation to shut down four cylinders under light loads, and turbocharging arrived as far back as 1983. With twin turbos and a new cylinder head design, introduced in 2015, today’s port-injected L-series engine boasts 530 horsepower and a locomotive-like 811 lb-ft of torque at only 1750 rpm in the Mulsanne Speed.

-
--
-

The L-series engine should not be confused with the modern 4.0-liter DOHC V-8 design that Bentley offers in the Flying Spur and the Continental GT. The engineering world isn’t entirely out of tricks that could still be applied to Bentley’s aged pushrod lump—General  Motors uses direct fuel injection in its latest small-block V-8, and the Dodge Viper V-10 employs more exotic cam-in-cam technology to allow wider variation of valve timing—but Dürheimer’s statement suggests his company is done spending to modernize its L-series. It’s still got some years to run, though. With the Mulsanne just updated for 2017, it appears its replacement could be five years away yet.

-

 

-lLGjcKtAHj0

Read Full Article

Share this post


Link to post
Share on other sites

Tired of these Ads? Register Today!


Tired of these Ads? Purchase Enhanced Membership today to remove them!
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.