JustinStrife

I never understood this fascination with displacement to horsepower ratios that people tout. To me, the external dimensions of an engine are much more important, than the internal dimensions, as a more compact design allows for more versatility on the overall car's design. Those DOHC engines tend to be more complex, wider, and more expensive than their pushrod brethren. Also GM tends to over build the engines IMO. 300rwhp LS1's that are capable of 700rwhp on stock internals. Not too shabby.

Aaron Keating

Ponies per liter is for people that don't know better. They don't understand how important actual external dimensions are, or that SBCs are like a Tardis. They're bigger than their outsides suggest. They hear "7.0 Liter" and think of some huge dinosaur. Because of their flat sixes, boxers, slant sixes, and super wide DOHC V6s.

They also don't understand that our engines are actually Lighter than their's. It's always funny hearing GTR fans talk about how "Gm can't even hit 100 horsepower per liter... and the GTR is well past it!", without realizing our engines are 70lbs or more lighter. (LS9 vs GTR)

Dominic Toretto

When you are comparing the weight of a GTR and ZR1 engine, does that include the turbocharges?

-Alex

drivestwin

While a person could use linear proportions to get a basic idea, I too agree that it would not be a linear relationship. More like a logarithmic or exponential relationship.

No way its linear.

455230

The math means nothing,in terms of the final power output the GM will come up with.

This engine should easily break 500 hp ,but it wont for marketing reasons.

It makes sense ,from GM's perspective to detune it initially,so that in year 3 they can bump the power up 25-30 hp with minimal effort.

As for the Camaro being horsepower king...who cares?.....It wont affect C7 sales.....Totally different market segment.

04_Z06_CE

One has to think the DOHC part plays a significant role in power. I do also think it will be around 480

OBSSSD

Unfortunately GM is too dumb to actually make the car with even 500hp from the factory. This WILL hurt sales quickly on the car once the early adopters get their units filled.

I would have bought a 500hp coupe, but now I have to wait for a higher hp model and pay way more money for it because they chose to sandbag so badly on this engine.

SBC_and_a_stick

Wasn't this thread posted before?

It's simple to see that DOHC motors with 4 valves per cylinder can flow more at the same lift. The same hp/liter would apply only to a bench racer.

There is really nothing to talk about here. /thread

sam90lx

It will take the Z version of the C7 to trump the output of the Z-28. Low production high $$$ track focused car. No way the C7 puts out 505!

sam90lx

Exactly! I would have bought one also...thats 2 sales they just lost!

BlueOx

Yeah, because so many more Z06s were sold than base/GSs.

Hot Rod Todd

My 1200 CC ZX12 Kawasaki motorcycle makes 2.6 hp per cubic inch, that does not mean that Chevy should be able to build a 977 HP small block. Volume increases on a logrithmic scale, not linear. Limits such as piston speed also prevent larger engines from achieving the RPM that smaller engines can reliably attain. The initial premise of this thread is flawed.

For the base model Stingray, GM seems to have been more concerned with a flat power curve than total horsepower figures. For most people it will make the car feel more powerful since many seldom do redline shifts. All that being said, I would not be surprised if there is quite a bit of power left on the table to help future sales. Once more data is in obtained about the engine, they can bring in more horsepower and be confident that it will still be reliable.

lt4obsesses

Yes, very true. You're knowledge and experience far exceeds mine. My comparison, however, is related more to the factory specs, which includes cost and regulatory factors. That and, though only skimming the linked article, considering that the V6 may also have similar components to the LT1 in terms of materials. Then it's just a matter of the crank is bigger, the pistons are bigger, the flwheel, flex plate bigger. This is more what I was looking at.

I'm more talking about the engines as they are built, not so much as they could be built. These are both engines that have to deliver reliability, durability, and maintain a profit margin, considering that they are subject to a 100,000 mile powertrain warranty. That said, they could very well make the LT1 a 700hp monster if they wanted, they just don't want to, at least not yet.

JoesC5

6.2L Mercedes engine has 622 horsepower. So why doesn't the GM 6.2L LS3 or LT1 have 622 horsepower? They are both normally aspirated and have the same displacement and both have VVT and DI.

It's more than just HP/L that determines how an engine is designed and for what application..

PRE-Z06

Agreed a smaller engine is easier to make more efficient as it doesn't require as much air.

PRE-Z06

The 505hp camaro still will not be faster than the base c7...

Halltech

Yep, you are right. Nothing new to report here.

sam90lx

Really.....

CivEngineer

Not my field of expertise in engineering, but it seems that there are so many different variables, no way a linear relationship would apply. Lots of thermal characteristic differences. When you start looking at areas vs outside circumferences in relation to cooling, flame face temperature gradients, etc, lots of differences that would affect efficiencies.

robvuk

Does no one here realize that a 3 liter motor revving to 10k rpm is the same total displacement as a 6 liter revving to 5k? The fact is that efficiency has not been significantly improved in decades. We still only get 25-30% of the power out of the fuel. That's why those more "efficient" high revving, high hp, low displacement motors STILL don't get any better mileage than a Corvette. All these different engine designs just make it possible to burn more or less of it in a given amount of time but in the end, they produce about the same power.

I would like to see the manufacturers start posting hp/lbs not hp/liter. Unfortunately they make it hard to find accurate weight and external volume measurements. Would you guys complain if GM had a motor that had pushrods with one valve per cylinder that made 500hp if it was the size of a shoebox? THAT should be the goal here, not hp per liter.