The Evolution of Chevy's Gen III V8

[RC45]

Pictures from the Houston Autoshow...

Interesting how GM has allocated the engines to their new homes. Bring on the LS7 :twisted: :twisted:

The LS1
I wonder who else will get LS1 power?
http://www.z06vette.com/gallery/data/500/3648RC45_LS101.jpg
http://www.z06vette.com/gallery/data/500/3648RC45_LS102.jpg

The LS6
I wonder if Cadillac will have exclusive use of the LS6 now - like the Northstar?
http://www.z06vette.com/gallery/data/500/3648RC45_LS601.jpg
http://www.z06vette.com/gallery/data/500/3648RC45_LS602.jpg

The LS2
The LS2 is going to be the next "standard" hot rodders fare I guess...

BTW, is that a typo on the LS2 spec chart... 2 valves? Are they scrapping the 3 valve head?
http://www.z06vette.com/gallery/data/500/3648RC45_LS201.jpg
http://www.z06vette.com/gallery/data/500/3648RC45_LS202.jpg

The LS7
THIS SPACE FOR RENT.

[blah]

Caddy doesnt have exclusive use of the Northstar anymore, remember the new Pontiac Bonneville GTX, or GTP wtf its name is has a detuned Northstar. Also i wouldnt be suprised if a Judge version of the Goat got a LS6.

[possessed_beaver]

mmmm.. pushrod crap

slight torque improvments, they need to work on "smart" engines IMO

[RC45]

LOL - this "pushrod crap" is lighter and cheaper than the "smart" engines are - and we hand many "smart" engined cars their asses every Friday and Saturday... ;)

As long as they keep building "pushrod crap" that is lighter and cheaper than anyone elses - while making the same or more power - we will keep buying 'em... :lol: LOL

[nthfinity]

LOL - this "pushrod crap" is lighter and cheaper than the "smart" engines are - and we hand many "smart" engined cars their asses every Friday and Saturday...

As long as they keep building "pushrod crap" that is lighter and cheaper than anyone elses - while making the same or more power - we will keep buying 'em... LOL


haha 8) rightly said, RC45.


BTW, is that a typo on the LS2 spec chart... 2 valves? Are they scrapping the 3 valve head?


and the question about the LS2 6.0 v8, that one is the engine in the standard C6; and when the Z series evolution arrives in a year or two, ive heard it will be the 3 valv system you are thinking of, all overhead valvs to push the engine to 500+ hp, and im quite sure similar torque numbers.

by the way, wouldnt it kick ass if they called it the ZL2 as im sure it will be the fastest production vette to the 1/4, as well as retaining its supercar handling :twisted: :twisted:

[graywolf624]

mmmm.. pushrod crap

slight torque improvments, they need to work on "smart" engines IMO

That pushrod crap is a newer tech then overhead cams, is cheaper and easier to work on, and tends to weight less. overhead cams can rev higher. Neither is better.

[oscargarza88]

i wanted to go to that auto show but i wasnt in hpuston at that time, how was it? and do u have more pics?

[RC45]

It was great - I posted pics in the "What did you see today" section...

[novass]

I wish I had a few of each sitting in my garage and some cars to put them into.

[possessed_beaver]

it all comes down to personal opinions in the end.
i guess i shoulden't be telling a bunch of american's that these canadian engine's are crap (IMO) because well.. they aint going to agree with me, lol
but they produce terable bhp/L and chew through alot of fuel, and the LS1 was having problems with piston's fucking up and other things, until they teflon coated them, and done other changes to them.

[RC45]

it all comes down to personal opinions in the end.
i guess i shoulden't be telling a bunch of american's that these canadian engine's are crap (IMO) because well.. they aint going to agree with me, lol
but they produce terable bhp/L and chew through alot of fuel, and the LS1 was having problems with piston's fucking up and other things, until they teflon coated them, and done other changes to them.

Yep - personal opinion.. :roll: the fact that these engines produce 350bhp & 400bhp (crank) stock - and with simple mods can handle 200hp shots of nitrous, and with cam and heads updates can produce 500bhp (crank) easily - with MANY people running 600hp (crank) daily drivers has nothing to do with these opinions I guess.

The kicker, when combined with the current transmission taht they are - the cars in question will deliver 25-30mpg all day.

These engines are simple to work on, cheap to modify and produce ass-raping horsepower... I guess that is just opinion... A Great opinion :D

[altezza]

here is an interesting article from GM
Gen IV V-8 Marks 50 Years Of Small-Block Performance (http://media.gm.com/servlet/GatewayServlet?target=http://image.emerald.gm.com/gmnews/viewmonthlyreleasedetail.do?domain=3&docid=1937)

btw, the LS2 (http://www.media.gm.com/events/autoshows/04naias/corvette/Corvette_Powertrain.htm) is an OHV 2 valves per cylinder engine, so it's not a typo

[graywolf624]

but they produce terable bhp/L and chew through alot of fuel,

2 things..
25-28 mpg is pretty damn good gas mileage for a car with 330+ hp. I bet you wont find another engine with similar performance..(if you do itd be rare).

The second thing.. bhp/Liter means nothing. It has no basis on anything in reality. Not on engine weight, not on reving ability, not on power.. nothing..
To give you an example..
the 4.6 liter v8 in the mustang gt.. weighs 100 lbs more then the 5.0 v8 it replaced.. It also weighs more then the 5.7 liter v8 in the camaro and vette.. which puts out more hsp.

[possessed_beaver]

in australia modified LS1's (they are modified in the factory, by various peformance devisions) and are under warenty and the companys are owned by chev, they consume about 20L/100km

and the average car STI goes through about 10L/100km
and whats the faster car in the end?

[RC45]

Dunno - have yet to come across an STi on the street that isn't 6 bus lengths behind me by the time we get to 140... ;)


... granted he does catch me at the next gas stop.. but it takes him a while... ;)

[possessed_beaver]

lol, fair enough
i cannot rely comment, because i don't own a sti, or haven't been in a corvette.

sti's can only rely get upto 120/130mph ne way :(

[RC45]

I am going to post 2 VERY interesting posts from the Z06 website. These 2 posts are the best summaries (granted more opinion than fact) of the very discussion at heart.

OHC or OHV - which is the "most" technologically advanced.

* "When a person says that a Small Displacement DOHC motor is more "technologically advanced" than a large displacement pushrod OHV motor they are actually showing a lack of understanding of the technology in question.

A Pushrod OHV motor can be and today often is just as technologically advanced as a Variable valve timing DOHC small displacement turbo motor. Why do I say that?

1.) OHV, DOHC, Turbos, Superchargers, etc are all technologies that have been around since the 1920s.

2.) Manufacturers choose a configuration based on design and purpose.

3.) Technological advancement is measured on total execution.

Case in point, Z06 vs. BMW M5. Both have V8s that make at or around 400 hp. BMW uses a DOHC 4.9 Liter V8. The Chevy uses a 5.7 Liter pushrod V8. At first glance one would think the Bimmer motor to be more “technologically advanced”, but is that so?

The Chevy motor makes more Horse Power and Torque.

The Chevy motor gets better Fuel Economy (19/28 vs 13/21) (Largely a function of weight, but also because the LS6 is more efficient)

The Chevy motor has better emissions (ULEV vs. the BMWs LEV)

The Chevy motor is dimensionally smaller.

The Chevy motor is cheaper (you can buy one at the parts counter for <$6K)

The Chevy motor is lighter (Check the Shipping weight)

The Chevy motor has fewer moving parts.

The Chevy motor contributes to a better CG. (Shorter deck height from a tighter OHV package lowers the CG)

The Chevy motor does a better job using less expensive parts.


Which Engine is more technologically advanced? The Chevy motor. It does its job better because it: creates more power, more efficiently while doing so with better fuel economy and emissions. It does all this using fewer parts, in a tighter package using less expensive materials at an overall lower cost.

That is the definition of “High Tech”"


*The above quote is from an old post with minor typographical and grammatical corrections made.

[RC45]

And the next quote:

Apples to Oranges...

The problem with this entire comparison is that you’re comparing very different cars/engines/sizes/fuel injections/etc.

If you want a much simpler comparison there is a much better choice. Compare a Corvette Z06 LS6 to a Corvette ZR-1 LT5. Here you have two engines of the exact came Cubic Inch displacement, and the exact same factory rated horsepower. Both are GM engines for Corvette. The LT5 however was designed by Lotus and built by Mercury Marine for Chevrolet.

LS6
5.7L V-8 16 Valve w/Sequential Electronic Fuel Injection
Crated Shipping Weight: 497 lbs
Rated HP @ Flywheel: 405 HP @ 6000
Rated Torque @ Flywheel: 400 @ 4800
Common RWHP: 355 @ 6000
Common Torque: 350 @ 4800
Compression 11:1
Bore/Stroke 99mmx92mm

LT5
5.7L V-8 32 Valve DOHC w/Multiport Electronic Fuel Injection
Crated Shipping Weight: 741 lbs
Rated HP @ Flywheel: 405 HP @ 6500
Rated Torque @ Flywheel: 385 @ 5000
Common RWHP: 371 @ 6500
Common Torque: 352 @ 5000
Compression 11:1
Bore/Stroke 99mmx93mm

Now here we have two very similar engines with very different technology. These two cars have very special places in my heart - as I am lucky enough to own one of each. I will give you my person opinions about each.

Although the Z06 is by far a better designed, better handling, nicer car - I feel the ZR-1's engine is by far more powerful. The main difference between the two cars is the Powerband. I wish I had two DYNO graphs to show you side by side.

The Z06 is much lighter, has better traction, and tighter suspension - which leads to faster launches off the line. Racing my two cars against each other in stock configurations - the Z06 is clearly the leader in like 0-30 MPH. After that, it’s all over. Soon as the ZR-1 gets to RPM it rips the poor Z06 apart.

A ZR-1's torque curve starts lower and then just pulls harder throughout its RPM range. The Z06 start higher, but is much more gradual and peters out near the end of its RPM range.

SotP acceleration in a Zo6 just slams you against the seat on takeoff, and then slowly trails off the faster you go. SotP acceleration in the ZR-1 is more gradual on takeoff, and you squish back harder in the seat the higher the RPM's get.

My Z06 stock tops out at about 168 MPH. I think that's pretty avg. My ZR-1 topped out at about 192 MPH when it was stock. Again pretty avg. This is the difference an OHC/Valve train motor has to a standard V8.

Anyone that says higher RPM engines are useless is an idiot, plain and simple. In the ZR-1 to Z06 comparison the top end difference is mainly because of the RPM/Torque difference at redline. If two engines produce the same torque but one has twice the redline RPM, then the high redline engine would have double the horsepower.


The second thing to compare about each engine is the true capabilities of the technology. To me that means what can you modify it to do.

The general consensus about the LT5 bottom end is that it generally can handle up to about 1000HP before you need to start changing internals. I think most of the modders here would say a LS6 can only handle about 550HP-700HP stock.

Many many many ZR-1 modders have their engines running safely to the 9000 RPM range. My ZR-1 with about $20k in mods produces RWHP 1048HP @ 8900 RPM on 92 octane fuel. Its top speed is 223 MPH. It has 114,000 Hard Miles on it and I have never blown an engine.

A close friend of mine has a ZR-1 that produces 1258 HP @ 9600 RPM. His is highly modified, but has held together pretty well for a 10 year old car.

Personally I know of nobody that has come near these numbers with an LS6. I also think if you put a slightly modified LT5 in a Z06 frame you would have a scary car.

Technology for OHC and multi-valve per cylinder engines, I believe dramatically opens up the top end horsepower. I have seen a 32-valve head package for the LS6 that has some impressive hp/torque numbers, while allowing a built LS6 to run much higher RPM.

The tradeoff of course is weight and cost. A crated LT5 is about 4 times the cost of an LS6. Repair costs are naturally a lot higher with an LT5. Even though it’s an aluminum head/block engine - its still almost 70% heavier. I think most OHC engines statistically require less maintenance. Surely you can't say these little Honda OHC engines break down too much. The fuel economy is about the same, although I expect that’s my driving style. I bet a passive driver would get better fuel economy out of a Z06.

These are just my opinions as an owner. I'm not a mechanic or engine engineer. I think overall it depends on what you wish the car to do, and how much upgradeability you want it to have.

I also think US carmakers don’t like producing cars with high top speeds. It was rumored for years that the real reason for the canceling of the ZR-1 was not high maintenance costs, but rather government and legal liability pressures to not make a high top speed car in the US.

Hope this info helps someone.

[nthfinity]

very well described indeed; as i have believed the for quite sometime that the ZR-1 motor was much better in many ways; although more expensive. much of my knowlege about the car has come from my roommate who's dad has owned 12 vettes, and his "last" one he will own is a 95 ZR-1.... one of just several hundred i believe. thanks :)

[graywolf624]

The biggest thing for me is I sure as hell wouldn't want a 741 lb engine in the front of a road racing car.

I can also think of several ls6 cars pushing close to 1000 hp... Hell.. gm had two concept versions running 9xx about 2 years ago in camaro/firebirds.
A few more problems. Pushrods are technically a newer technology by about 20 years.

Moreover his comments about the power band are slightly flawed. The main reason for the dropoff is that the tranny in the ls6 cars are designed with the final gear for fuel economy. The same thing can be seen in the camaros.. where the final two gears are overdrive. Hardly a benefit for performance, but plays a big part in those great gas mileage numbers. Frankly, If I had a choice I'd go to a more performance oriented gear all the way through the transmission range. That being said I would also not care about the high speed. What does going over 170 mph get you? What track can you do that on? There might be two real tracks I know of where if your good enough you can overrun 170 mph in a car that started life as a street car(nascar ovals are not real tracks).

"Anyone that says higher RPM engines are useless is an idiot, plain and simple. In the ZR-1 to Z06 comparison the top end difference is mainly because of the RPM/Torque difference at redline. If two engines produce the same torque but one has twice the redline RPM, then the high redline engine would have double the horsepower. "
Tis also slightly off.. The real concern here is the length of the power band. Take the honda s2000 older version for example. It has a huge redline, but in a choice on engines to put in you better believe I'd have an engine with a lower redline and a larger torque band. The largest benefits to rpm range obviously are the ability to run numerically higher gears, possibly have a larger power range, and higher top speed. None of these are guarenteed on a dohc motor. See the ls1 power range compared to the s2000 power range..

The choice of engine type comes down to application.. What do you want to do with the engine? Each type has it's advantages.
I can even think of advantages to carburated versus fuel injected, diesel versus gas, and rotory versus cylinders.

[Nocturn]

Well said, from my experiance anyone who says one is better than the other doesn't know what the hell they are talking about. Either one can be better depending on application and intended goals.

[RC45]

Well said, from my experiance anyone who says one is better than the other doesn't know what the hell they are talking about. Either one can be better depending on application and intended goals.

Ironically - this is the point you are missing in your other comments... :roll:

You ever think that the "feeling" the LT1 gave was because of the "entire package" - rather than the LS1 feels less torquy... (or what ever you actually said)

[Nocturn]

Not when they are both in manual Camaros, albeit 5 years apart they changed very little between the two styles.