Figured you girls would like this LS9 638 HP 604 TQ

[Fr33way]

I cant get over that he said the engine is so primitive.

Pushrod DESIGN is NEWER than DOHC.

DOHC came to be around 1920 while pushrods were developed and released by Oldsmobile (Rocket V8) right around 1950.

Ignorance FTL.

[OneDurtyZ]

Car and Driver-pushrods good and bad

By Larry Webster


A pushrod is basically a metal tube designed to transfer the reciprocating motion of a valve lifter, riding on the camshaft, to the valve.

I found the pushrod fascinating 20 years ago, back when I was a high-school car geek devouring car magazines. It was about the time the Japanese car invasion began and Detroit started to worry about loss of market share here. In the mid-'80s, Detroit stuck by the pushrod, and nearly every available engine used it. Domestic cars were for the most part, however, mediocre contraptions that allowed foreign automakers to make inroads into the U.S. market. Back then our 10Best Cars competition had five spots for domestics and five for imports. In 1983, the pickings were so slim that the Chevrolet Caprice Classic made the list.

When asked what made Japanese cars better, critics gave a variety of answers, but one stuck in my mind: While the Americans produced crude, underperforming pushrod engines, the Japanese were turning out sophisticated four-cylinder, single- and double-overhead-cam engines with twice the number of valves per cylinder.

The idea of locating the camshafts in the cylinder head was not new, but to a populace still unaware that a 1929 Duesenberg Model J, for example, had double overhead cams and four valves per cylinder, the overhead-cam engine sounded advanced, exotic.

The pushrod was the scapegoat for all that was wrong with Detroit. "No doubt about it. In the '80s, the pushrod was a hated component, a symbol of the uncompetitiveness of the domestic industry," says Sam Winegarden, GM's chief engineer for small-block V-8s.

I called Winegarden because I've always been fascinated by GM's decision to stick with the pushrod when it introduced a new small-block V-8 in 1996.

By the '90s, many domestic four- and six-cylinder pushrod engines had been scuttled in favor of overhead-cam designs. In 1995, Ford axed its venerable pushrod 16-valve V-8 for a V-8 that still had just 16 valves but now ran with a pair of overhead cams.

Keeping the pushrod seemed like yet another example of the General's hanging on to its glory years. But since then, I've come to see that, for a mass-produced V-8 engine, the pushrod layout has more advantages than disadvantages.

"Power is a function of airflow, pure and simple," says Winegarden. "If you're not going to fill the cylinder with valves, why have an overhead cam?"

Although you could design a V-8 engine that uses pushrods to operate four valves per cylinder, the layout lends itself to using just two. Four valves generally have greater total valve area than two, thus creating greater airflow and more power. In the case of the Chevrolet Corvette Z06 and its pushrod two-valves-per-cylinder 405-hp, 5.7-liter V-8, Winegarden says, "We've been able to meet the performance requirements by using more displacement. Two more valves per cylinder would get us another 10 percent in total valve area."

A modern engine is a dizzying array of compromises as designers strive to meet power, cost, reliability, and emissions demands. The Vette V-8 would ultimately have more power if it had four valves per cylinder, but it would lose ground in cost, complexity, and physical size.

"On the Vette, performance density is only beaten by some of the big Ferrari or heavily boosted engines," Winegarden continues. One of the huge advantages of the pushrod V-8 layout is its clever use of space. The camshaft and the pushrods lie in the unused area between the cylinder banks. A DOHC or SOHC V-8 is much wider and a little taller because the camshafts are on top of the cylinder heads.

Enthusiasts often talk about how much power an engine produces as a function of the combined volume of the cylinders (power per liter). But what's often overlooked is the power produced compared with the outside dimensions of a motor.

The small-block is a compact engine. I did some rough measurements of the Z06's V-8, the DOHC V-8 in the Porsche Cayenne S (335 hp, 4.5 liters), and the Northstar V-8 in the Cadillac SRX (320 hp, 4.6 liters). The small-block was about six inches narrower than the Porsche V-8, two inches shorter than the Caddy's V-8, and close in length.

That may not sound like much, but it gives designers more freedom to position the engine for good weight distribution and leaves ample room for suspension and steering components.

Don't forget about the weight advantages. The Vette's engine has one camshaft and a small drive chain that's connected to the crank. A DOHC V-8 has four camshafts and drive gears, beefy heads to hold the shafts, and two long chains. "Our V-8 is a simple and elegant design. It's pretty easy to put together, which helps the reliability, and costs," says Winegarden. He estimates a $400 saving over a DOHC motor. And, of course, with fewer parts comes less weight. (Winegarden says the aluminum small-block is 44 pounds lighter than the Northstar.)

GM also used this architecture for its truck engines. Spreading the tooling and design costs over a large number of vehicles reduced the per-unit engine cost. That's one reason the $52,385 Z06 can compete with sports cars costing twice as much.

So if the pushrod design makes such a good V-8, why does GM make a DOHC V-8 Northstar? "I'm not going to touch that one," laughs Winegarden. GM's party line is that some customers want what it calls "high-feature engines." Winegarden does admit there are some refinement benefits to the DOHC layout, but personally, I don't find the Vette's engine to be a bit unruly.

GM is no longer the pushrod's sole champion. Dodge has reintroduced the pushrod Hemi V-8. And this year, Toyota is running in the NASCAR Craftsman Truck Series with a newly developed pushrod V-8. Of course, that's a motor used only for racing, but is it so far-fetched to wonder if Toyota would make a production pushrod V-8?

Such an engine would be cheaper to build than the complex DOHC V-8 that's now in the Tundra pickup, and Toyota would also realize some marketing benefits from the huge racing investment. The irony is almost too sweet to imagine.

[seanrg1116]

Please just give up now. The vette will beat your car in any venue be it a track, drag race, what ever. You got a Z because it is way cheaper than a vette and no one can blame you for that. I hate chevy but to be honest the ls series motor is f'ing awesome and thats why "high tech" mazda and nissan guys pull the dual cam, variable timing, wankle or whatever to put these motors in.

it can beat all but one



7:38 around the ring as a base model GTR. The v-spec is said to be capeable of laping the ring 18 seconds faster. that would make it faster than the full carbon fiber zonda. and its powered by one of nissans v-series motor



but i am not hating on the ZR1 it will surely be FAST AS HELL. Bang for buck corvettes have always delivered.

[VteckTuna]

Pushrod DESIGN is NEWER than DOHC.

DOHC came to be around 1920 while pushrods were developed and released by Oldsmobile (Rocket V8) right around 1950.

Ignorance FTL.

+1

[tj1986c]

Pushrod DESIGN is NEWER than DOHC.

DOHC came to be around 1920 while pushrods were developed and released by Oldsmobile (Rocket V8) right around 1950.

Ignorance FTL.

Uh, I think that's what Transamkid was talking about .

TJ

[RUFFIAN]

Chevy had a Duel overhead cam 32v motor in the ZR1 back in the 80's. very boost friendly

[GTScoob]

Sick motor but I hate car companies bragging about HP/L when they're using forced induction to increase VE. Honda can brag about it with the S2000 which made 120HP/L NA as can any host of 700+ NA V8s but not a supercharged V8.

And to the 350Z nutswinger, I'd say that the LS series motors have way more R&D put into perfecting the 'old tech' pushrod setup than your VQ. These new Vette motors have much more exotic internals than your VQ and end up being a more powerful, lighter, simpler, smaller package than your V6. The head engineers obviously dont see the need for a DOHC engine when a pushrod setup will do the same job and with less rotating parts.

You dont see Evo guys bitching about how the 4G63 motor has been around forever, in fact most of them brag about how easy it is to make power since the platform is tried and true. The LS is the same way, tried and true results and proven power.

[JITB]

Sick motor but I hate car companies bragging about HP/L when they're using forced induction to increase VE. Honda can brag about it with the S2000 which made 120HP/L NA as can any host of 700+ NA V8s but not a supercharged V8.

And to the 350Z nutswinger, I'd say that the LS series motors have way more R&D put into perfecting the 'old tech' pushrod setup than your VQ. These new Vette motors have much more exotic internals than your VQ and end up being a more powerful, lighter, simpler, smaller package than your V6. The head engineers obviously dont see the need for a DOHC engine when a pushrod setup will do the same job and with less rotating parts.

You dont see Evo guys bitching about how the 4G63 motor has been around forever, in fact most of them brag about how easy it is to make power since the platform is tried and true. The LS is the same way, tried and true results and proven power.

u pulled those thoughts out of my head i swear u did!!

from the fi hp/l statement, to the 4g63 comment...lol

crazy

[OneSlow5pt0]

yea,the LT5 was a lotus built DOHC 32v engine, i believe it came out in 1991


but not to beconfused with LT1 or LT4

[cwhiteboy]

...I mean the all fiberglass body is great, but why can't they look at Lotus and get some ideas, hell thats what Carrol Shelbey did

Actually, the last Z06 suspension was designed by Lotus, and TVR helped with the car as well, but I can't remember how . Either way, the Corvette is a magnificant car, and this new 600hp engine is :boobies: . For Chevy.

[Fr33way]

Car and Driver-pushrods good and bad

By Larry Webster


A pushrod is basically a metal tube designed to transfer the reciprocating motion of a valve lifter, riding on the camshaft, to the valve.

I found the pushrod fascinating 20 years ago, back when I was a high-school car geek devouring car magazines. It was about the time the Japanese car invasion began and Detroit started to worry about loss of market share here. In the mid-'80s, Detroit stuck by the pushrod, and nearly every available engine used it. Domestic cars were for the most part, however, mediocre contraptions that allowed foreign automakers to make inroads into the U.S. market. Back then our 10Best Cars competition had five spots for domestics and five for imports. In 1983, the pickings were so slim that the Chevrolet Caprice Classic made the list.

When asked what made Japanese cars better, critics gave a variety of answers, but one stuck in my mind: While the Americans produced crude, underperforming pushrod engines, the Japanese were turning out sophisticated four-cylinder, single- and double-overhead-cam engines with twice the number of valves per cylinder.

The idea of locating the camshafts in the cylinder head was not new, but to a populace still unaware that a 1929 Duesenberg Model J, for example, had double overhead cams and four valves per cylinder, the overhead-cam engine sounded advanced, exotic.

The pushrod was the scapegoat for all that was wrong with Detroit. "No doubt about it. In the '80s, the pushrod was a hated component, a symbol of the uncompetitiveness of the domestic industry," says Sam Winegarden, GM's chief engineer for small-block V-8s.

I called Winegarden because I've always been fascinated by GM's decision to stick with the pushrod when it introduced a new small-block V-8 in 1996.

By the '90s, many domestic four- and six-cylinder pushrod engines had been scuttled in favor of overhead-cam designs. In 1995, Ford axed its venerable pushrod 16-valve V-8 for a V-8 that still had just 16 valves but now ran with a pair of overhead cams.

Keeping the pushrod seemed like yet another example of the General's hanging on to its glory years. But since then, I've come to see that, for a mass-produced V-8 engine, the pushrod layout has more advantages than disadvantages.

"Power is a function of airflow, pure and simple," says Winegarden. "If you're not going to fill the cylinder with valves, why have an overhead cam?"

Although you could design a V-8 engine that uses pushrods to operate four valves per cylinder, the layout lends itself to using just two. Four valves generally have greater total valve area than two, thus creating greater airflow and more power. In the case of the Chevrolet Corvette Z06 and its pushrod two-valves-per-cylinder 405-hp, 5.7-liter V-8, Winegarden says, "We've been able to meet the performance requirements by using more displacement. Two more valves per cylinder would get us another 10 percent in total valve area."

A modern engine is a dizzying array of compromises as designers strive to meet power, cost, reliability, and emissions demands. The Vette V-8 would ultimately have more power if it had four valves per cylinder, but it would lose ground in cost, complexity, and physical size.

"On the Vette, performance density is only beaten by some of the big Ferrari or heavily boosted engines," Winegarden continues. One of the huge advantages of the pushrod V-8 layout is its clever use of space. The camshaft and the pushrods lie in the unused area between the cylinder banks. A DOHC or SOHC V-8 is much wider and a little taller because the camshafts are on top of the cylinder heads.

Enthusiasts often talk about how much power an engine produces as a function of the combined volume of the cylinders (power per liter). But what's often overlooked is the power produced compared with the outside dimensions of a motor.

The small-block is a compact engine. I did some rough measurements of the Z06's V-8, the DOHC V-8 in the Porsche Cayenne S (335 hp, 4.5 liters), and the Northstar V-8 in the Cadillac SRX (320 hp, 4.6 liters). The small-block was about six inches narrower than the Porsche V-8, two inches shorter than the Caddy's V-8, and close in length.

That may not sound like much, but it gives designers more freedom to position the engine for good weight distribution and leaves ample room for suspension and steering components.

Don't forget about the weight advantages. The Vette's engine has one camshaft and a small drive chain that's connected to the crank. A DOHC V-8 has four camshafts and drive gears, beefy heads to hold the shafts, and two long chains. "Our V-8 is a simple and elegant design. It's pretty easy to put together, which helps the reliability, and costs," says Winegarden. He estimates a $400 saving over a DOHC motor. And, of course, with fewer parts comes less weight. (Winegarden says the aluminum small-block is 44 pounds lighter than the Northstar.)

GM also used this architecture for its truck engines. Spreading the tooling and design costs over a large number of vehicles reduced the per-unit engine cost. That's one reason the $52,385 Z06 can compete with sports cars costing twice as much.

So if the pushrod design makes such a good V-8, why does GM make a DOHC V-8 Northstar? "I'm not going to touch that one," laughs Winegarden. GM's party line is that some customers want what it calls "high-feature engines." Winegarden does admit there are some refinement benefits to the DOHC layout, but personally, I don't find the Vette's engine to be a bit unruly.

GM is no longer the pushrod's sole champion. Dodge has reintroduced the pushrod Hemi V-8. And this year, Toyota is running in the NASCAR Craftsman Truck Series with a newly developed pushrod V-8. Of course, that's a motor used only for racing, but is it so far-fetched to wonder if Toyota would make a production pushrod V-8?

Such an engine would be cheaper to build than the complex DOHC V-8 that's now in the Tundra pickup, and Toyota would also realize some marketing benefits from the huge racing investment. The irony is almost too sweet to imagine.

What is this s'hit? You were wrong about it being "old tech". Just leave it.

[Fr33way]

Uh, I think that's what Transamkid was talking about .

TJ

Word, I was talking to the guy with the engine that was an evolutionary cost cutting version of mine (which I am not saying is amazing) and thought that DOHC was the absolute 133t.

[seanrg1116]

small block chevy

VS.

VQ35

um will some one show me a VQ motor making 1000hp on pump gas. I have seen it with a small block and its "old " tech.

but i do like the VQs they make good power for what they are.

How about maintiance costs I have a couple friends at nissan dealers and they say the vq is expensive to work on

but i think we all know how easy a small block can be. well hell any push rod is easy to work on

[Blitanicle99]

Say goodbye to the good old hand built 427 however. This is just a baseline vette motor with a blower. A true 427 would have been the appropriate motor to build to make a corvette supercar.

[dsm3g]

Pushrod technology... thats cute

[hellomynameiscarlos]

i don't know about talking up lotus very much as far as the blocks in there elise. If i remember reading correctly they use the same block that is in my 07 focus. it just kinda suck that you spend all that money on a little rocket only to be using the same parts from a focus. that just what i think and it does give my focus 1 plus on cool points...lol

[Crazy Asian]

hRM I want to swap this in the PRelude. LETS SEE WHAT HAPPENS!!!

[OneSlow5pt0]

i don't know about talking up lotus very much as far as the blocks in there elise. If i remember reading correctly they use the same block that is in my 07 focus. it just kinda suck that you spend all that money on a little rocket only to be using the same parts from a focus. that just what i think and it does give my focus 1 plus on cool points...lol

elise is toyota engine,i belive same one from the MR2S and celica

but lotus does build bad V8s like he Espirit

[revsk8erdude]

oh im sure it makes a lot of torque, it'd be unbeatable at pulling my boat, or hauling my grandparents travel trailer, my engine isnt designed for that. I'm sure its one of the best american produced engines, but you cant argue that its very primative compared to other engines. Imagine the power it would have with a more efficent 4 valve per cyclinder arangment, or DOHCs, you know modern equpiment

yeah, i agree. like a DOHC VTEC motor.

[fight club]

few things id like to comment on from this thread:
1. about the lotus: the lotus elise and exige use the new celica motor, with the exige being supercharged.
2.about the 427 would of been a better idea: chevy has all ready stated that they planned on using the new z06 engine or and blowing it but the cylinder walls were too thin.
3. this bull**** with the gtr-v is getting rediculous. they say it will goes around 16 second slower. it has not been proven nor tested. not saying its not a bad ass car but my god.
4. vette > 350z convertible in ease of working on, sportyness, and realibility. vettes have had a few problems but not many. i dont remember a single recall for a vette year where the tranny blew out regularly and was factory replaced (cough:: 350z
5. while you could make a road racing 350z for the price of the zr1, which is 100k, that 350z would ride like **** on highways etc. the vette can drive to the track, switch tires and rape the **** out of em, and then drive home.
6. ferrarri v8's, with all their technical "modern" **** are not better. they rev out the ass and for what? 12+ sec quarter mile. and depending on model, not too good of track times. they are a exotic brand by nature.
7. and for the hp/L stuff. yea the s2000 does make more. it also has a ****tier powerline than most cars. it makes its power by revving out.
8. the whole not being modern thing agian, the eaton blower sitting on that engine was just designed in the past 5 years, and is considered one of the best to date. not modern at all huh?

[mp5o]

thanks, but dont bother with facts, else the fanbois will pummel you

I only see one fan boy here ^^^

[josh green]

if its power you want, buy the z06, add twins, save money. 7L > 6.2L. The 427 has iron sleeves, so i cannot see them not being boost friendly. The internals are BEEF on that LS9 though. I want to know why chevy chose titanium for the rods. If I am not mistaken titanium (though stronger than aluminum) fatigues faster than aluminum, and power gains NA were found in much higher rpms. If its the same block as the 427, with the deck plate and lower displacement, it better rev to like 8500rpm. Expect $20k+ for a crate IF its available.

[hellomynameiscarlos]

elise is toyota engine,i belive same one from the MR2S and celica

but lotus does build bad V8s like he Espirit

you are correct, i was reading the other page i was looking at wrong however they do use the Ford Duratec motors in the lotus seven replicas alot, and in some of the Elise race cars such as this one. click the link below

CLICK ON ME

[Fr33way]

you are correct, i was reading the other page i was looking at wrong however they do use the Ford Duratec motors in the lotus seven replicas alot, and in some of the Elise race cars such as this one. click the link below

CLICK ON ME

Um, so?

[koukis14]

2 values per cyclinder and a single cam, oh GM, you 1970s motors alway make me laugh

Nascar Cup cars make 800 h.p. and wil sit at 9500 rpm all day long and have 2 valves per cylinder. Top Fuel Dragsters and Funny car make 8000 HP and have 2 valves per cylinder. Maybe you should learn something about cars next time you post on a car forum.

[hellomynameiscarlos]

Um, so?

i was just saying that some of the more exotic automakers must think that we American auto makers and out antique ways of designing engines is good for something. Not that my 4 cyl. duratec has a fraction of the new vette motor. any other questions?

[JITB]

i was just saying that some of the more exotic automakers must think that we American auto makers and out antique ways of designing engines is good for something. Not that my 4 cyl. duratec has a fraction of the new vette motor. any other questions?

duratec is a european motor..

[hellomynameiscarlos]

o design by porches sold to ford... i guess well now its a ford motor