NG Poll > Scratch OHCs And Pay $800 Less?

With the auto industry being such a cut-throat business these days, it makes you wonder if Ford might not switch back to a pushrod design for the their trucks, and dare we say it... their Mustang?

----- By DAVE GUILFORD

DETROIT -- A key factor in General Motors' ability to play an aggressive price game often goes unnoticed or even draws criticism - GM's heavy use of pushrod engines.

Performance buffs belittle pushrods as crude and outdated. But pushrods - expected to make up 62 percent of the 5.5 million engines GM will sell in North America this model year - save GM roughly $800 per unit against comparable overhead-cam engines, analysts say.

That enables GM to boost incentives, add standard equipment or offer a V-6 cheaper than a competitor's overhead-cam version.

Edward Koerner, vice president for powertrain engineering operations, says pushrods fill the high-volume, price-competitive segment of GM's engine lineup. Targeted at consumers who want a reliable engine but don't care about its inner workings, pushrods "give you some feature-content opportunities," Koerner says.

"Maybe there are other things that are more important in a segment, and because the powertrain price was down, you can offer other comfort features at that price point," he says.

For example, dual-zone air conditioning is standard in the base Chevrolet Impala. The feature is either lacking or found only in upper-end models of key competitors such as the overhead-cam-powered Honda Accord and Toyota Camry, which outsell the Impala nonetheless.

Japanese automakers overwhelmingly favor overhead cams. GM lines up pushrods against domestic rivals as well.

For example, its Chevrolet Silverado and GMC Sierra full-sized pickups

- sporting pushrod V-8s - compete with the Ford F-150 and its overhead cam V-8s. Dodge offers overhead cam V-8s as standard equipment on Ram pickups but has built a successful marketing campaign for the optional

5.7-liter Hemi pushrod V-8.

Overhead cam, or multivalve, engines generally use one or two camshafts per cylinder head to open and close four valves per cylinder. They typically offer better power at higher RPMs and smoother idle and are more suited to variable valve timing, which improves torque range, fuel economy and smoothness and reduces emissions.

Pushrods, also known as overhead valve engines, use a single camshaft placed in the engine block below the cylinders, which have two valves apiece. Typically, they provide better low-end power. The configuration is more suitable for cylinder deactivation.

With fewer camshafts and valves, pushrod engines require fewer parts, which cuts cost and simplifies production. They also have an advantage in weight and size.

Koerner termed the cost difference "very, very significant" but would not give a figure. Brett Smith, director of product and technology forecasting for the Center for Automotive Research in Ann Arbor, Mich., says the difference is about $800, including premium materials often found in overhead-cam engines.

Smith adds that refinements have lessened many of pushrods' disadvantages: "It's no longer a low-tech, low-precision pushrod. It's a low-tech, high-precision pushrod."

Lindsay Brooke, senior powertrain analyst for CSM Worldwide in Farmington Hills, Mich., notes the Chrysler group has created an advertising buzz around its pushrod Hemi V-8s. Pushrods suit much of the U.S. market, particularly trucks, Brooke says: "GM and now Chrysler, with its V-8 Hemi, have a strong value proposition."

GM's engine lineup also includes "high-feature" engines, mostly overhead-cam engines and "image engines" for high-end vehicles, Koerner says. GM's strategy depends on offering the suitable engine for each consumer niche. But matching engines and market segments can be a sensitive business. For instance, GM has pushed the 2004 Pontiac Grand Prix as a performance vehicle. But it is powered by a 3.8-liter pushrod V-6.

That drew the scorn of a reviewer for The New York Times, who contrasted the pushrod to import competitors' "modern, overhead cam, multi-valve engines - many of them with variable valve timing for smoother, more flexible power delivery."

Gordon Wangers, managing partner of Automotive Marketing Consultants in San Diego, says enthusiast-magazine reviewers "are very critical these days of anyone running pushrods."

Wangers says although some pushrods are excellent, they reinforce enthusiasts' sense that GM is wedded to outdated technology. "The problem is the marketing, the image of 'yester-tech,' " Wangers says.

But most mainstream consumers don't care about engine specifications beyond horsepower and the number of cylinders, he says.

"I'm not sure the buyer of a Buick LaCrosse would know or care if the engine was multivalve or pushrod," Wangers says. "I don't think a Camry buyer would know either, for that matter."

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Here's a little NG poll. If you could get a Chrysler-style Hemi or a GM-style LS2 pushrod engine (a Ford design of course) under the hood of your next new Mustang for 800 bucks less than a overhead cam design, what would you do?

1) Buy an OHC Mustang 2) Buy a Hemi/LS2-style Mustang

Patrick '93 Cobra '83 LTD

Reply to
Patrick
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I guess I'm old fashioned because I bought my 2003 GMC Sonoma because it was a good old pushrod engine. I looked at it as being simple and reliable, and it made more power down low. Of course getting the GM discount thru my dad didn't hurt either. :)

Years ago I had a Tarsus with a 2.3 liter pushrod four cylinder. It would spank a four cylinder Mustang of equal vintage in the stop light nationals. They just couldn't get off the line as well as I could with the extra low end.

MadDAWG

Reply to
MadDAWG

Reply to
Michael Johnson

snipped-for-privacy@aol.com (Patrick) wrote in news: snipped-for-privacy@posting.google.com:

operations,

comfort

pickups

overhead

optional

camshaft

valves

parts,

advantage

materials

Pontiac

Without hesitation, Door Number Two. Both the Hemi and LS2 (not to mention the LS6) out-gun the Mustang GT's OHC - more power for less money. A no-brainer.

The $800 in savings could go for other "fun" things.

Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC

Reply to
Joe

Ford doesn't need a pushrod engine to make power, the OHC is more efficient. The new Mustang GT will be getting 300 horses from the 3v 4.6L, and the current Mach 1's are getting significantly more than their rated 305 out of the 4v version. (closer to 320 than the n/a Cobras were getting in 2001) The Chevy 5.7L was making what, 350 in the Vette & 375 in the Z06? Which has now been upped to a 6.0L to make 400 horses in the new C6. What Ford needs is a modular 5.0 and a performance version of the 5.7 which can can come close to or equal these HP numbers in n/a form. (350 & 400) The n/a 4.6L just doesn't have the torque a 5.7L could provide, which we all know when combined with the rpm ability of a performance OHC can add up to some impressive horsepower numbers. I'd love to see a modular whipple 4v 5.0L in the next SVT Mustang factory rated at 450+ horses, and like the current Cobra's mod-ability it would allow plenty of easily found aftermarket horsepower. The Lightning could use a whipple 5.7L for more torque and similar horsepower numbers.

Reply to
WraithCobra

snipped-for-privacy@aol.com (Patrick) wrote

snip

I'd take the OHC motor. And that's with the knowledge of an additional cost advantage not mentioned in the Detroit News story, that an OHV motor is a lot cheaper to hotrod than an OHC motor. On the OHV, just one cam shaft, one little old timing set, just 16 lifters, 16 pushrods, 16 spring sets, 16 retainers, just 16 ports to tweak, vs. two or four times as much stuff to replace and rework with the OHC. Also, the OHV has a packaging advantage all over the cammer. Just look at a 347 Ford or a 383 Chevy small block making 400-500 easy NA hp out of a package about as big as an orange crate.

But forget all that, I'll still take the cammer.

180 Out TS 28
Reply to
180 Out

The Taurus pushrod 4 was 2.5 liters based on the 200/250 I-6 Falcon/Mustang engines. It was good for low-end in the rather light FWD MT5 Taurus, at about 110 hp compared to the 95 or 100 hp 2.3 liter OHC RWD Mustang at about 95-100 hp. The Taurus was overall still underpowered with this engine for the most part, it was even more obvious in automatic transmission (3-sp. only) trim.

Rob

Reply to
trainfan1

A 2004 Z06 makes 405 HP. The LS1 in the Z28 is rated around 300 horsepower. On a chassis dyno most stock six speeds can put that much to the rear tires. Plus, they have a very flat torque curve. And they have much room for improvement. They have cast iron exhaust manifolds and single exhaust.

I spend almost every weekend at the drag strip. I pay close attention to the Camaro/Mustang guys. It's very hard to find completely stock cars, most at least play with the computer and add a K&N dirt sucker or a CAT back exhaust. The Camaro/Birds run in the 13's and the Mustangs are at least a second behind them. I'm waiting for a new Cobra to show up. There are two "messed with" Lightning's here in the 12's. I'm no fan of the 5.4 but you can't knock how they run.

I would also go with the OHC engine, if it ran like one. Why Ford made the Mustang OHC engine try to imatate a 5.0 push rod engine is beyond me. They tune it for low end torque, and shut the fuel off when it should be pulling. My shitbox Contour is 2.5L and makes 200 horses. Has about as much low end torque as a Briggs and Stratton 5 horse, but let it get to 4,500 RPM and it will make it up. According to the owners manual you can drive it at 6,000 RPM all day. It has embarrassed many a high performance rice car. I'm dreading the day it grenades, but I can't complain about how it runs.

Al

Reply to
Big Al

Tough decision, guess it's not hard to figure which way I'd go :-)

97 5.0 coupe

TIM -aka- MUSTTANGUY "at" AOL "dot" COM

formatting link

Reply to
Musttanguy

"Big Al" wrote

Not that this has anything to do with your post, but here's a funny quote I read on the way to work this morning in the "Roddin' at Random" section of the May '04 Hot Rod: "Quick Quotes: 'I don't exactly classify the '03 Cobra motors stock, because they don't come with all Ford parts. I read somewhere that the rods are actually Manley pieces and I think they even have ARP bolts.' -- An upset LS1 owner making excuses in light of Ford's more potent 4.6L redefining the meaning of 'stock.'"

Yeah, look out for those ARP bolts, worth 10 rwhp at least, 20 if you run the decal too. :)

180 Out TS 28
Reply to
180 Out

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