GM plans to transform small-block V8

[vztrt]

Not really much there, but it is a good start to see what GM will do to combat Coyote.

http://www.goauto.com.au/mellor/mell...2576BE00008E54

General Motors backs V8 engine, planning substantial upgrade

2 February 2010

By JAMES STANFORD

GENERAL Motors has declared its commitment to V8 engines and is planning a “substantial transformation” of its pushrod small-block V8.

Last month’s Detroit motor show might have featured much green technology, but GM vice chairman Bob Lutz backed the GM V8, while Fiat and Chrysler Group CEO Sergio Marchionne promised a long future for the Hemi V8 and Ford presented its new-generation Coyote V8. Mr Lutz indicated the GM small-block V8 would be given a significant mechanical upgrade, and hinted that technology such as direct injection and variable valve timing could be employed.

Asked if GM planned changes for the small-block V8, Mr Lutz said: “Nothing we would want to announce today.

“The V8 is going to have to undergo a substantial transformation and it is going to need new timing technology. A lot of things have to happen with the small block.”

It is not yet clear if GM would move away from pushrods or instead develop a variable overhead cam valve system.

Mr Lutz said the GM small block, which was introduced in 1955, has constantly evolved.

“The small block has always been like grandfather’s axe – you know where it has been in the family for 100 years and sometimes you change the blade and sometimes you change the handle,” he said.

“Because you never change the blade and the handle at the same time it is still grandfather’s axe, even though the blade and the handle have probably been changed about six times so far.

“It is the same old small block, but if you go back in history there is nothing the same.”

The GM small-block V8 family includes the Holden Commodore’s 6.0-litre Gen IV, which now features displacement on demand cruising fuel economy technology as well as the HSV 6.2-litre LS3 and the 7.0-litre LS7 which made a brief appearance in the W427.

Mr Lutz made it clear that eight-cylinder engines still had a role in the GM family, but would need to become leaner.

“The V8 engine is not dead, not by any means,” he said.

“There is plenty of potential to make V8s more fuel efficient. For instance direct injection as opposed to indirect injection, cylinder shut-down (for the LS versions) – there is still quite a bit of technology left that can be deployed in V8 engines to make them more fuel efficient.

“It will continue to be popular and it will be a significant proportion of the portfolio. I think we need to continue to develop the engine.”

There is a view that V8 engines are at odds with the new generation of green engines being put forward by most manufacturers, including Chevrolet’s electric range extended Volt, but Mr Lutz argues there is room for V8 engines alongside GM’s new range of green powerplants.

“We do hybrids and electric vehicles and extended range stuff because that is where the world is moving and our overseas subsidiaries like Holden will benefit from all that technology that comes on stream, but we are still probably the world’s largest producer of V8 engines and proud of it and have some truly excellent cars with V8 engines such as Cadillacs and Holdens,” he said.

Mr Marchionne told GoAuto that the Chrysler Group would still regard the Hemi V8 as an important powerplant under its new leadership.

“It will continue to be popular and it will be a significant proportion of the portfolio,” he said.

Like Mr Lutz, Mr Marchionne said plenty could be done to make the Hemi, which also has displacement on demand, more efficient.

“I think we need to continue to develop the engine,” he said.

[Mr X]

How many pushrod engines are currently in production around the world today I wonder?Not to sully in any way the legend of the small block Chev but its time it joined the 21st century.

[LethalLeigh]

Originally Posted by Mr X

How many pushrod engines are currently in production around the world today I wonder?Not to sully in any way the legend of the small block Chev but its time it joined the 21st century.

Probably the same reason they still use carbies in NASCAR. The Yanks have done it for so long not many do it as well.

[smoo]

Originally Posted by Mr X

How many pushrod engines are currently in production around the world today I wonder?Not to sully in any way the legend of the small block Chev but its time it joined the 21st century.

You might wanna find out just how (in)efficient the internal combustion engine really is, then you might realise been on the dohc high horse/band wagon is a waste of time.

[Mr X]

Originally Posted by smoo

You might wanna find out just how (in)efficient the internal combustion engine really is, then you might realise been on the dohc high horse/band wagon is a waste of time.

What band wagon?Why isn't every high performance manufacturer in the world using pushrod engines eg Aston Martin ,AMG,Lamborghini etc etc.
Should we bring back carbies and distributors too ?

[burnz]

Originally Posted by Mr X

What band wagon?Why isn't every high performance manufacturer in the world using pushrod engines eg Aston Martin ,AMG,Lamborghini etc etc.
Should we bring back carbies and distributors too ?

not this argument, thats like saying why are fuel cars pushrod and not ohc.
not all porsces were ohc, some were both.
to ask a strait question do you really need complex motors?
millers, sarich

the most simple motors is ram jet, pulse jet, ****el.

[Mr X]

Originally Posted by burnz

not this argument, thats like saying why are fuel cars pushrod and not ohc.
not all porsces were ohc, some were both.
to ask a strait question do you really need complex motors?
millers, sarich

the most simple motors is ram jet, pulse jet, ****el.

I'm not on here 24/7 so I don't know whats been discussed before-but yes you might have something there with the KISS principle .
A lot of the stuff we get in the workshop SEEMS TO BE unneccesarily complicated.

[4Vman]

Originally Posted by burnz

not this argument, thats like saying why are fuel cars pushrod and not ohc.
not all porsces were ohc, some were both.
to ask a strait question do you really need complex motors?
millers, sarich

the most simple motors is ram jet, pulse jet, ****el.

The OHC fuel engine got banned because it was too powerful compared to the class std pushrod engine, fuel engines make plenty enough power without needing to introduce or improve technology.

Why do people use extreme racing examples to try to justify a production based stance?

The best measure of power production efficiency is KW/L of displacement....

With the world heading towards smaller engines as a marketing advantage KW/L of displacement will be a critical measurement in years to come...

[Bad Bird]

Why? Pushrods engines are lighter and more compact, and since large displacement engines don't need to spin to 9000 rpm to make power it makes perfect sense.

[Mr X]

Originally Posted by Bad Bird

Why? Pushrods engines are lighter and more compact, and since large displacement engines don't need to spin to 9000 rpm to make power it makes perfect sense.

I'll leave the experts to explain to you the advantages of four valves per cylinder and variable cam timing.

Would you like to see a new Ferrari with a pushrod V12?

[LethalLeigh]

Originally Posted by Mr X

I'll leave the experts to explain to you the advantages of four valves per cylinder and variable cam timing.

Would you like to see a new Ferrari with a pushrod V12?

There was a good Bob Lutz interview a while back where he compared the LS7 to BMWs M5 V10. Both made 500hp or there abouts but despite the fact it was 2L bigger in capacity it made more torque lower down, weighed less and was a physically more compact motor.

I'll admit there's certain efficiencies to be had with a DOHC design but the bang for your buck quotient of an American developed pushrod V8 is hard to top.

[Windsor220]

Be interesting to see how variabe valve timing would work on a pushrod engine.

[robertjp]

Originally Posted by Windsor220

Be interesting to see how variabe valve timing would work on a pushrod engine.

How about designing a lifter in two halves, with the lifter situated stationary in the block and hydraulic pressure determining lift. This pressure is controlled by a valve which is computer controlled (what else) from the main oil feed lines. If the system malfunctions then the lifter (sic) reverts back to normal operation.

(sorry this is being done on the fly and without a diagram is really hard to explain, double sorry to any engineers who will undoubtedly say that this will not work due to ....)

Robert.

[Mr X]

Originally Posted by LethalLeigh

There was a good Bob Lutz interview a while back where he compared the LS7 to BMWs M5 V10. Both made 500hp or there abouts but despite the fact it was 2L bigger in capacity it made more torque lower down, weighed less and was a physically more compact motor.

I'll admit there's certain efficiencies to be had with a DOHC design but the bang for your buck quotient of an American developed pushrod V8 is hard to top.

Don't get me wrong.I own two pushrod V8's which I love and one quad ohc-but pushrods are antiquated technology and GM know they have to move forwards.Bigger capacity requires more fuel and cylinder shut down seems to me to be a bit of band aid.

[Bad Bird]

Originally Posted by Mr X

I'll leave the experts to explain to you the advantages of four valves per cylinder and variable cam timing.

Would you like to see a new Ferrari with a pushrod V12?

Uh, the Ferrari is a high revving plant that can utilise the high rpm valvetrain stability offered by dohc. It's all antiquated technology, pushrods are not anymore dinosaur than ohc...

[SSD-85]

Originally Posted by Bad Bird

Uh, the Ferrari is a high revving plant that can utilise the high rpm valvetrain stability offered by dohc. It's all antiquated technology, pushrods are not anymore dinosaur than ohc...

Correct, Pushrod actuation was actually utilized (if not invented) after OHC. So that makes OHC pretty dinosaur to me. It should be appropriately termed that OHC is being used for the direction that engine tech is going in. I wont speculate how OHC is better than Pushrods, since I really don't have any factual information, but there is obviously a very good reason since nearly all engine manufacturers are moving onto OHC.

[Windsor220]

OHC is just more efficient. With less parts/space between cam and valve. Multivalve can flow better too. Just uses up more space overall with the multiple cams.

[Wally]

Originally Posted by Scotty85

........ I wont speculate how OHC is better than Pushrods, since I really don't have any factual information, but there is obviously a very good reason since nearly all engine manufacturers are moving onto OHC.

The generally accepted notions by design engineers are:

pushrods have a heavy valve train, which limits reliable rpm;
pushrod valve trains flex, limiting aggressive grinds;
the tradeoff is to increase capacity, resulting in fuel economy loss when on power;
pushrod engines are cheaper to make than complex DOHC castings.

[chuckles]

the chrysler hemi v8 is pushrod still

[US kills Falcon]

*yawns*

[chevypower]

Well Ford is moving back to 2v on the 6.2. It takes more energy to drive 2 cams than one, so having 2 large valves on that engine sounds good to me. Maybe this is why Ford says the 5.0 will get similar fuel Econ to the 5.4. But when talking about the 6.2, Ford says it will get better fuel econ than the 5.4.
I think the most reliable way to drive a cam is with a chain. For efficiency? Maybe pushrod. I kind of go with chain for reliability cos I bet I'm one of very few people in the world that has thrown a rod and broken a timing belt on the same night in two different cars obviously. They were both Holdens too!

[Swordsman88]

Originally Posted by chevypower

Well Ford is moving back to 2v on the 6.2. It takes more energy to drive 2 cams than one, so having 2 large valves on that engine sounds good to me. Maybe this is why Ford says the 5.0 will get similar fuel Econ to the 5.4. But when talking about the 6.2, Ford says it will get better fuel econ than the 5.4.
I think the most reliable way to drive a cam is with a chain. For efficiency? Maybe pushrod. I kind of go with chain for reliability cos I bet I'm one of very few people in the world that has thrown a rod and broken a timing belt on the same night in two different cars obviously. They were both Holdens too!

The fuel efficiency gains of the 6.2 over the 5.4 are probably dependent on the vehicles they are in. The 5.4 would have alot more trouble trying to pull a F350 than an FG falcon....hence if you put a 5.0 in the falcon you may not burn that much less but putting the more powerful 6.2 in an F350 you will... Its a bit like the 3.0 SIDI holden v6 debacle...its not that the engine is all that bad (though its far from good) its simply that it can't save fuel with its given performance in a commodore.....

I believe Ford's statements was that the 5.0 would burn the same as the 4.6 anyway....are they putting 5.0 in F series??

[chevypower]

Originally Posted by Swordsman88

are they putting 5.0 in F series??

Yep, but less power than the Mustang has.
2011 F-150 engines are: (with probable HP/lb-ft)

3.7L V6 280-300/280
5.0L V8 360/360
3.5L V6 EcoBoost 400/400
6.2 V8 411/434

Super Duty (F250/F350)
6.2 V8 411/434
6.7 V8 diesel 400/750

Things couldn't be any more interesting in the Ford world in my opinion.

[jpd80]

In development Ford built a 5.0 off the 6.2 but couldn't get the efficiency they needed.
Conversely, the larger bore hemi configuration in the 6.2 necessitates dual spark plugs
for shorter flame front ensuring all the mixture is burnt.
So even though the 5.4 could have been saved as a long stroke Coyote,
the 6.2 is a better design for that size.

I would consider both 5.0 an 6.2 well designed for their respective sizes and intended purposes.

[chevypower]

I wasn't aware of a 5.0 "Boss" motor under development. I know the Boss was a originally to come as a 5.8 and 6.2. 5.8L for regular F150 and Expedition. The 6.2 was for Navigator and premium model F150s. But that 5.8 was axed. I believe people are finding out about this 5.8 and making the assumption that there is a 5.8L Coyote engine in development, which I don't believe for 1 second is going to happen.

[mcnews]

Originally Posted by chevypower

Well Ford is moving back to 2v on the 6.2. It takes more energy to drive 2 cams than one, so having 2 large valves on that engine sounds good to me. Maybe this is why Ford says the 5.0 will get similar fuel Econ to the 5.4. But when talking about the 6.2, Ford says it will get better fuel econ than the 5.4.
I think the most reliable way to drive a cam is with a chain. For efficiency? Maybe pushrod. I kind of go with chain for reliability cos I bet I'm one of very few people in the world that has thrown a rod and broken a timing belt on the same night in two different cars obviously. They were both Holdens too!

Two valve engines are generally much more efficient at lower rpm due to better gas flow speeds. Thus why some engines have two valves operating at low rpm then switching to four valves at higher rpm. Trying to get the best of both worlds.

[xbgs351]

Originally Posted by chevypower

Well Ford is moving back to 2v on the 6.2. It takes more energy to drive 2 cams than one, so having 2 large valves on that engine sounds good to me. Maybe this is why Ford says the 5.0 will get similar fuel Econ to the 5.4. But when talking about the 6.2, Ford says it will get better fuel econ than the 5.4.
I think the most reliable way to drive a cam is with a chain. For efficiency? Maybe pushrod. I kind of go with chain for reliability cos I bet I'm one of very few people in the world that has thrown a rod and broken a timing belt on the same night in two different cars obviously. They were both Holdens too!

Don't you mean 4 camshafts?

Besides it will still take less energy to turn 4 camshafts in a OHC engine than one in a pushrod engine. The reasons for this are:
-A OHC Bucket system has no lateral movement, unlike a rockers on a valve tip of a pushrod motor.
-A pushrod motor has friction at the lifter, both ends of the push rod and at the rocker bearings.
-A pushrod motor requires far higher valve spring rates to control the heavier valves, and greater lifts.

[4Vman]

Coyote will finally force GM to look at better technology like DOHC...

[Burnout]

Originally Posted by 4Vman

Coyote will finally force GM to look at better technology like DOHC...

Hope the top of the heads stays together - not like the 307's where the rocker gear came loose and fell off all the time.

[outback_ute]

Originally Posted by Bob Lutz

“The small block has always been like grandfather’s axe – you know where it has been in the family for 100 years and sometimes you change the blade and sometimes you change the handle,” he said.

“Because you never change the blade and the handle at the same time it is still grandfather’s axe, even though the blade and the handle have probably been changed about six times so far.

“It is the same old small block, but if you go back in history there is nothing the same.”

Surely the Gen III was new block and heads at the same time?

Originally Posted by Scotty85

Correct, Pushrod actuation was actually utilized (if not invented) after OHC.

Are you sure? Not aware of any engines pre-1900 that didn't use pushrods.