Chadder

iTrader: (2)

I can't speak for the Hemi, but that's hilariously untrue for LS engines. The 5.3 is a better motor than the 5.4 could ever have wished to be. There was a Camaro on here that swapped a 4.8 in just to beat on the Ford guys and take away their excuse for having more displacement. He was quite successful in whooping a lot of ***. I'll try to find the thread.

AWDTBSS

that 13.1 is a joke road and track got 12.9 and a local around here has done plenty of 12.7-8s stock

assasinator

i dont care what ford does. who really does? my points have nothing to do with ford. my point is, GM doent HAVE to build these big motors(cubic inches displacement).


5.3 liter 320hp is only 80-100hp below what it needs to be to compete with the ls-3, 6.2 hemi, 5.0 coyote.

a purpose built 4.8 can surely be built for pure racing to beat a stock ls-3/hemi/coyote, but that isnt 50 state legal.

i think gm could truly rule with a 5.0 - 5.5 liter dohc 500hp engine. and get great gas mileage.

assasinator

if you could see my driveway right now, there is a 99 jeep wrangler, 96 cadillac SLS, 2000 cadillac deville, a 36 foot 454 powered GM chasis motorhome, and a mustang gt. there will be a 2007 cadillac CTS-v when i pay off the new 2011 GT.

im not brand specific. but american UNION built for sure.

IF gm can DI these motors and get 30mpg EPA it would be a miracle. if they could congratulations. they had better do it before gas reaches $4.00 a gallon again, or its all over.

assasinator

all of my family has either worked at the DELCO plant in kokomo indiana, or at the chrysler transmission plant there. my family and union brothers are COUNTING on GM to get it right and not fold.

JD_AMG

WEIGHT is the enemy, making a lighter car will yield better gas mileage, NOT decreasing displacement. Let me ask you, why is it that EVERY auto maker is INCREASING their displacement on their performance cars? You name it, Ford, Dodge, GM, Ferrari, Lamborghini, Porsche etc. ALL are increasing displacement.

What mindset are you refering to? Making one of the lightest and physically smallest and most efficient V8 engines on the market? (lighter and smaller than many V6s as well...)
And what is Ford doing? Making less power with MORE weight, MORE size, and WORSE gas mileage.

Give me a "Big ole" 6L LS2 with 400hp that gets you 28mpg over a 5L engine that is more costly, bigger and heavier and gets only 26mpg...

A 4.8L Vortec is a truck engine, and not tuned to make power, nice comparison kiddo.

Cadillacs 4.6L is more expensive, heavier, physically larger, makes less power/torque, and gets worse gas mileage than a "low tech" LS1. There is a reason they don't make it anymore.
You need to get off the whole "displacement argument", it is IRRELEVANT. What is relevant is physical size and weight.

JD_AMG

Clearly you don't get it at all. A smaller displaced LSx based engine would NOT get better gas mileage. And especially a bulky, heavy DOHC engine wouldn't get better gas mileage making the same power.
Find me a 500hp sports car that can get 19/26mpg. GM is the ONLY one doing it, and they are doing it with a 7L engine that is physically smaller, and lighter than most V6s on the market...

94Mustang302ci

The 5.4 in the 2000 Cobra R had 385hp and the Aussie 5.4 in the Boss 290 made 388hp. both were N/A

Irunelevens

To be fair, MOST of the reason the LSx cars get the gas mileage they do is gearing. Double overdrive in the T56 really helps quite a bit.

96RamAirTA

iTrader: (6)

i think the guy just like his motors small with lots of shafts!

96RamAirTA

iTrader: (6)

im pretty sure the ZO6/ZR1 dont use a t56

Irunelevens

Yes, they use a T6060. But the 6th gear ratios still range from (IIRC) .50-.67. Which is LOW.

Blakbird24

iTrader: (24)

GM does have a smaller DOHC V8 making nearly 500hp. The LC3 motor is 4.4L and puts out 469hp with a supercharger. Problems being - it's damn expensive, and gas mileage is only so-so. It's not bad, but it's nothing compared to the LS motors.

See again we are at this stupid argument that GM uses low-tech motors. It's just a retarded argument when these low tech motors are beating EVERYTHING else out there in EVERY category - they are smaller, lighter, more efficient, they make more power, AND on top of all that, they are cheap to fix. It's really hard to make an argument against that, you just have nothing to stand on.

kain01

The argument is moot because ALL engine's today are OHV. The OHC engine is simply an altered OHV engine, because overhead valve turned out to be better than the old side valve engine's they used to use. Not only that, but there is less than ten years between the invention of David Dunbar Buick's OHV combustion engine and the early use of Ferdinand Porsche's DOHC engine's. The better argument to be would be comparing singengle to dual overhead design's because they both use the overhead valve design that is so low tech. They just swap the cam area, not the valve area. The only true modern engine out there at the moment is the Wankel rotary, and we all see how well it's doing.

deelong4002

iTrader: (8)

God i hope GM doesnt go to DOHC in their performance cars. They are so much more complex, and really the value / horsepower just isnt there. Everyone can argue about how the pushrod engine is old technology, but the fact of the matter is, right now, its beating out all of the exotic/new technology out there, pound for pound, and its so easy to mod.

LS1LT1

iTrader: (16)

That is a big part of it but GM/LSx cars aren't the only ones using 6 speed/overdrive transmissions. Others use them too yet they still don't necessarily deliver the same (or even close) fuel economy.
Some even have 7 speeds.

Heater

After driving my buddies T/A with a 6 speed, I was jealous at how low the rpms were in 6th gear.


That .50 gear ain't no joke for highway mauling.

offroadfury6

iTrader: (8)

GM's 3800 V6 engines are a classic and you can't kill the strong bastrds either...haha

Irunelevens

The 7/8-speed transmissions are more to always be able to have the engine in the right part of the powerband. Not necessarily for maximum gas mileage was cruising.

oddwraith

iTrader: (1)

^^^I believe they are both reasons, not one or the other.