Pontiac Solstice Forum banner

1 - 6 of 6 Posts

·
Mod Emeritus
Joined
·
7,468 Posts
Discussion Starter #1
GM news release:

http://media.gm.com/servlet/GatewayServlet?target=http://image.emerald.gm.com/gmnews/viewmonthlyreleasedetail.do?domain=74&docid=19106

FOR RELEASE: 2005-09-29

POPULAR MECHANICS Awards GM 3.9 V-6 For Breakthrough Technology



New York - General Motors' new 3.9-liter V-6 has been recognized for ground-breaking technology by the editors of POPULAR MECHANICS in the publication's first "POPULAR MECHANICS Breakthrough Awards." The announcement was made today at the American Museum of Natural History and will be featured in the October issue of POPULAR MECHANICS, on newsstands nationwide October 11, 2005.

The POPULAR MECHANICS Breakthrough Awards recognize ten individuals and teams, including one winner of the Breakthrough Leadership Award, that are helping to improve lives and expand possibilities in the realms of science, technology and exploration. Additionally, POPULAR MECHANICS highlighted a separate group of ten consumer products that represent milestones in design and engineering.


The 3.9 V-6 has been awarded for the innovative adaptation of variable valve timing, an industry first for overhead valve engines.

"General Motors keeps finding ways to advance overhead valve engines and the 3.9-liter V-6 used in the Impala reaches new levels," said James Meigs, editor-in-chief, POPULAR MECHANICS. "For their continued success and innovation, we're proud to recognize GM with a 2006 Breakthrough Award."

The 3.9 is part of an all-new family of advanced overhead valve, 60-degree V-6 engines. The engine is designed new from the block up and in addition to variable valve timing, incorporates a host of advanced, premium features, including a variable intake manifold, piston-cooling oil squirters, and an advanced 32-bit engine controller.

"The breakthrough development of variable valve timing for the 3.9 demonstrates the continued relevance of the elegant overhead valve engine design," said Dr. Gary Horvat, assistant chief engineer, V-6 engines. "We're honored that the editorial team at POPULAR MECHANICS recognize the significance of this technology."

The variable valve timing system incorporates a vane-type camshaft phaser that changes the angular orientation of the camshaft, thereby adjusting the timing of the intake and exhaust valves to optimize performance and economy, and helping lower emissions. Within its range of operation, it offers infinitely variable valve timing in relation to the crankshaft. The cam phasing creates "dual equal" valve timing adjustments. In other words, the intake valves and exhaust valves are varied at the same time and at the same rate.

The award-winning, 240-horsepower 3.9 V-6 is available in the 2006 Chevrolet Impala, Monte Carlo, Malibu SS, Malibu Maxx SS and Uplander; Pontiac G6 GTP and SV6; Buick Terraza; and Saturn Relay.

POPULAR MECHANICS is published by Hearst Magazines, a unit of The Hearst Corporation (www.hearst.com) and one of the world's largest publishers of monthly magazines, with a total of 19 U.S. titles and 142 international editions. Hearst reaches more adults than any other publisher of monthly magazines (76.3 million according to MRI, spring 2005). The company also publishes 19 magazines in the United Kingdom through its wholly owned subsidiary, The National Magazine Company Limited.

General Motors Corp. (NYSE: GM), the world's largest automaker, has been the global industry sales leader since 1931. Founded in 1908, GM today employs about 317,000 people around the world. It has manufacturing operations in 32 countries and its vehicles are sold in 200 countries. In 2004, GM sold nearly 9 million cars and trucks globally, up 4 percent and the second-highest total in the company's history. GM's global headquarters are at the GM Renaissance Center in Detroit. More information on GM can be found at www.gm.com
 

·
Registered
Joined
·
1,143 Posts
Now how many read that and didn't think, "I'd take that in my Solstice!" :lol:
 

·
Mod Emeritus
Joined
·
7,468 Posts
Discussion Starter #3
MAKsys said:
Now how many read that and didn't think, "I'd take that in my Solstice!" :lol:
I've driven a G6 GTP with that engine (an auto too) and it is a really responsive engine in that car. The car liked to leap forward with even moderate stabs at the gas. It would turn the much lighter Solstice into a rocket! I'd take it! :lol:
 

·
Registered
Joined
·
1,068 Posts
Huh?

Why is the 3.9 better than Honda's 3.5 that has been around for >5 years and produces more HP w/ better fuel economy? GM even uses it in the Saturn Vue.
 

·
Senior Member
Joined
·
5,600 Posts
Now if they could just drop the 3.9L in a Solstice! :willy:
 

·
Mod Emeritus
Joined
·
7,468 Posts
Discussion Starter #6 (Edited)
65MGB said:
Why is the 3.9 better than Honda's 3.5 that has been around for >5 years and produces more HP w/ better fuel economy? GM even uses it in the Saturn Vue.
Who said either was better or worse?

Well, that is hard to say based on what we know. Does it REALLY get better mileage? Or are we going to compare the very inaccurate EPA ratings. (For instance, the GM 3800 engine generally gets better than EPA ratings in real world use, where as the Nissan's new V6's generally get worse than EPA ratings in real world use). EPA ratings are for general comparison, and even then they are not very good compared to real world use. Another factor to consider is that the 3.9L is tuned to be a performance engine and has the gearing to match. I am sure less agressive gearing would raise it's mileage figure to be more in line, but since it is meant to be a "sport" option GM is not tuning it that way at this time. Remember, just because they didn't doesn't mean they can't.

Really, the fuel economy argument is a mute point unless you put both engines in an identical vehicle with identical gearing. With different cars, you have different weights, transmissions, gearing, different unsprung weight, different wheel sizes, different tires that may have greater or lesser rolling resistance, different coefficients of drag, potentially differen weights of oil and on and on. It all can add up. For instance, the G6 GTP is rated 18/29 city highway (manual) the Vue AWD 19/25. That means the G6 gets better mileage than the Vue, but we don't know which engine gets better mileage in an equivalent vehicle with equivalent drivetrain making the mileage argument a moot point when comparing just engines. The G6 has a lower city rating, but it has jackrabit gearing off the line. The Vue eases off the line more (I have already driven a 2006 V6 Vue quite a bit the last couple months). The G6 has better highway mileage, which may be a tradeoff of drag. Of course, those big 18 inch wheels and tires hurt highway mileage with their greater drag and wind resistance. Really, comparing two cars mileage and boiling it down to which engine is more efficient is just not a good way to compare.

Power, the Honda V6 is rated 250 HP and 242 lb-ft of torque. The 3.9L GM engine is 240-241. So the honda motor is up 10 HP and 1 lb. It is more, but not stageringly so.

So those are the numbers, but what about the intangibles. What is the weight of each engine, the power curves, the cost to produce (which affects the cost of the vehicle), how much physical space they occupy, what they do to the weight balance of the vehicle.

I do not have those stats for these two engines, but they would be very important in chosing which one is "better." I can make some general observations. OHC engines tend to have their weight higher, because of the added weight of the overhead cams and hardware. This hardware tends to make them take up more space too, as they are higher and wider than a comparable OHV. They also tend to be heavier engines overall too. So the OHV engine would typically give you a smaller, lighter package that did not adversly affect the center of gravity of the vehicle as much. That is important in a vehicle's ride and handling.

OHC engines also have more moving parts, adding to their complexity which could hurt reliability and raise production costs. For example, GM's 3.6L DOHC V6 costs significantly more for GM to manufacture than their OHV engines. That is why they continue to offer OHV engines in their cheaper vehicles while offering DOHC engines in their more premium vehicles (Cadillacs, upper end Buicks mostly for now).

On the positive side, a DOHC engine has better breathing capability which adds to higher RPM horsepower. Since the 3.5L Honda engine is a SOHC engine, it doesn't really enjoy this advantage. The DOHC engines typically are easier to tune for better economy and emissions through the use of VVT technology. With this new 3.9L VVT, that advantage is reduced, although there are versions of VVT on DOHC engines that are more intricate than that of the 3.9L VVT. Again, not on the SOHC 3.5L Honda V6.

The release doesn't mention it, but the 3.9L has also been developed for displacement on demand which will allow it to run on just 3 cylinders to conserve more fuel on the highway.

As for overall power, lets get both motors on a dyno and see which actually has more power. It is nice to speculate on manufacturers published numbers, but any honest enthusiast has to admit that published numbers are rarely accurate, and automakers are known for overrating and underrating those figures. In this comparo, the 250 HP in the Vue is by the old SAE testing method, and the 240 in the G6 is based on SAE Certified testing. Some Honda engines which have been SAE Certified have lost abotu 10 HP from the old SAE method, so that 10 HP lead could evaporate too.
 
1 - 6 of 6 Posts
Top