Official numbers for the LT4 are...

650/650 SAE

 

That off GM's website? You need one of those in the Vette.

 

That's some pretty awesome power. I bet it gets way better MPG than a GT500 too. I wonder how tall it is. The lack of titanium fancyness might make it cheaper than the 26K crate LS9.

I highly doubt that 1.7L blower will have much head room on it though since it's already 5000RPM higher.

 

Nope. Got it from the Detroit Section SAE dinner/vehicle event last night.

 

They actually went over this when they unveiled the engine. While its smaller its still much more efficient than the ls9's blower runs cooler temps and is capable of more rpm's. It's got much more room to grown, I'll bet with a decent port job, pulley and supporting bolt ons these things will near 800whp no problem

 

^^ This guy gets it ^^

 

"General Motors (GM) has released the official SAE-certified power statistics on the all-new 2015 Chevrolet Corvette Z06's LT4 supercharged engine, revealing the Z06 to be the most powerful production car ever made by GM. The 2015 Z06 features a 6.2-liter V-8 engine that will crank up to 650 horsepower and can deliver 650 lb.-ft. of torque at 3,600 rpm."

"The LT4 small block sets a new benchmark for power and torque at GM," said Steve Kiefer, vice president, GM Powertrain Engineering. "The engine also puts the new Corvette Z06 on par with the most powerful supercars offered in America, while delivering performance with impeccable manners that make it suitable for daily driving."

Just off idle, the LT4 engine produces 457 lb.-ft. of torque, and at 2,800 rpm it's producing 625 lb.-ft. By comparison, says GM, the V-12 engine in the Ferrari F12 Berlinetta, which features 12% more horsepower, doesn't reach its peak torque of 509 lb.-ft. until it's running at 6,000 rpm.

"Torque is the pulling power of an engine and the LT4's abundance of it at every rpm helps the Z06 accelerate quicker and respond nearly instantaneously," explained Jordan Lee, chief engineer for small-block engines. "It's the very definition of power on demand."

"It's also worth mentioning that the LT4's supercar performance numbers are achieved with an engine that is nearly the same size as the very compact LT1 engine introduced in the 2014 Corvette Stingray," Lee said. "The power density of the LT4 makes it one of the smallest and lightest 650-horsepower engines in the industry."

Features specific to the Z06's new LT4 engine include:

aluminum cylinder heads;
lightweight titanium intake valves;
machined, forged powder metal steel connecting rods for reduced reciprocating mass;
compression ratio of 10.0:1, enabled by direct injection;
forged aluminum pistons with stronger structure;
stainless steel exhaust manifolds and an aluminum balancer that are lighter than their LT1 counterparts.

 

Hmm they're going back to this stuff now? The LS7 had titanium rods and the LS9 forged steel I think, so wonder why they are going with something seemingly weaker and less expensive in their ZR1/Z06 replacement...

 

It looks to me that every area has been improved...

 

Forged titanium rods to forged powdered metal rods is an improvement to you?

 

Let's talk longevity...

Yes. You're right. The car sucks. Forged anything... Jeez. What were they thinking. They should have just used regular floating rods.

 

Really? By putting in weaker rods in a boosted application?

And what about the LS9/LS7 rods lacked in "longevity"?

 

They put the weaker rods in there so you guys with heavy feet can break throw one and they'll gladly charge you an arm and a leg to repair it. And GM surely knows that you Vette owner's are gonna drive like bats out of hell. So, for the 25% of powdered rods that breaks, it'll be ok. No different than the all-too-common LS7 cylinder wall probably that was known to crack, but we all still loved the LS7. Do y'all get how all this works now? How else does a car company make extra money. Trust and believe, dealerships don't make majority of their money on car sales. It's the service that rakes it in.

 

Kinda hard for said company to "make money" with these "inferior" parts when they're covered under the GM Power train warranty...

 

I'm not saying they're "inferior". I'm just wondering why they would be going backwards in the company's halo car that's costing over 100k when they've already done such a piece before.

I mean it seems every single bit of the new engine is an improvement over the old one. Yet for some reason they go with a heavier weaker rod. I get not upgrading it and just staying with something strong that worked before, but going backwards when everything else moved forward?

 

Awe, you know the same old rhetoric..."This isn't a warranty issue." Or...."It seems that you've been racing or redlining the motor." Or...."Warranty only covers______and not the_____." type of deal. (Fill in the blanks with your exact auto problem that they won't cover.) You know how it always goes. Oh, and you better not have done any type of alteration to the motor which I know us guys love to do. Rather it be as simple as adding a cold air intake or something as serious as swapping out a new cam. They'll most definitely say you've voided the warranty. Also, you know the owners manula that gives you all of those service guideline, such as 15k, 30k, 60k, 90k, etc services that are due? If they look in their computer and see you haven't done one of those scheduled services, they'll blame any failure on you as a result of not properly maintaining the vehicle according to GM's rules. And we all know, probably 75% of any make and model car owner doesn't follow that book because for one....... it's expensive. They do sneaky stuff like ask where have you been getting your oil changes and then ask for the receipt's. Then they'll blame it on the type of oil you've been using if it was done by an outside company like Jiffy Lube or Quick Lube, etc. So, finally after you realize you're responsible for the repairs and ask how much is it...they'll politely say, "$1800, $2250, $2500 or $2750." That sir, is how they make their money.

 

LTX swaps... LTX swaps for everyone

 

Only thing I can guess is they strengthened the pistons and put less in the rods bc the rods haven't ever been a problem. Nothing but good though having a better piston.

 

Resleeved LS6 by the late Dave Diluca (RIP) at Agostino Racing Engines in Toronto back in 2002.

Amazing engine......took 173,000 miles of pure abuse and never made a hiccup.

.

 

What on earth makes you think they're weaker?

They obviously handle 650 HP well enough that GM will put a warranty on them.

The Ti rods are just lighter and more expensive (and subject to fatigue failures because Titanium, like aluminum, doesn't have a fatigue limit...)