VIDEO: GM explains tech details of ZR1 LS9 engine

Click the image above for more high-res pics of the ZR1
The ZR1 Corvette is one serious piece of American metal, with the athleticism of a track star and the brute power of drag racer. While light weight materials, magnetic damping and 15.5-inch Brembo brakes sounds impressive, the real meat lies under the hood of the fastest ever production Corvette. GM's supercharged 6.2L small block V8 packs at least 620 hp and nearly 600 lb-ft of torque, and its duty is to finally put the Corvette into the supercar club. We were lucky enough to spend some time with Ron Meegan, the assistant chief of GM's small block engine program, and he gave us an engineer's view of the supercharged LS9 engine. Hit the jump to learn why GM didn't use the 7.0L V8 from the Z06, why the Eaton supercharger is so special, and whether or not GM is being modest with the ZR1's projected 620 hp rating. 






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Reader Comments (Page 1 of 2)
why not the LS2/LS7? 11:40AM (3/04/2008)
blowers are for Fords
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Shipey 11:52AM (3/04/2008)
Blown engines making "only" 500hp are for Fords.
Making 620+ naturally aspirated HP simply can't be done while retaining the civility needed for a production Corvette. If you'd ever riden in a 600+ hp naturally aspirated car you'd know what I mean. They are loud, shaky, cantankerous, and no where near streetable. The blower was the right choice. Though twin turbos would've been sweet as well...
why not the LS2/LS7? 12:00PM (3/04/2008)
That's great. If I want a smooth ride I'll get an XLR-V. This is a Corvette.
I don't really agree that shakiness is inherent to big NA engines, well except maybe at idle. I bet the 10K revving FXX engine is even less shaky than this blown V8.
GM has not only taken the low road here, but they've copped out and said the high road sucks anyway. This isn't the same attitude that made the LS1 or a 427 SMALL block.
Jnel 1:07PM (3/04/2008)
....and the FXX costs what? 1.7 MILLION? A laughable comparison, at best.
why not the LS2/LS7? 1:18PM (3/04/2008)
You're making my point for me. If you think the roughness can be taken out with some more (expensive) engineering, then it isn't inherent to NA, which is my point.
MikeW 1:52PM (3/04/2008)
Sure, there would be 'shakiness' if you constrained yourself to a crossplane crank V8, and a fixed single camshaft.
There would be too much lope from too much overlap. And virtually no chance to make emissions legality.
http://www.youtube.com/watch?v=DG65mcICyuY&feature=related
http://www.youtube.com/watch?v=RAxVlBWFmew&feature=related
The V12 in the Enzo & FXX is odd firing. 65-55
http://www.mechadyne-int.com/vva-reference/papers/the-impact-of-variable-valve-actuation-on-engine-performance-and-emissions.pdf
why not the LS2/LS7? 2:02PM (3/04/2008)
Oh please, don't use Ferrari as an example of how to do emissions or fuel economy. There's no ground to stand on.
Ferrari has nothing on the small block V8 when it comes to efficiency or emissions. They do clearly have big advantages on smoothness everywhere but at idle.
Golferal 6:05PM (3/04/2008)
Actually, Fords just "blow"
98c5lingenfelter 6:17PM (3/04/2008)
what is wrong with a blower? They make great power across the
Chad 11:48AM (3/04/2008)
I can appreciate the tech and power this car has but it doesn't do anything for me.
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remy 11:55AM (3/04/2008)
That ferrari-esque window on the hood isn't well executed at all...it looks tacky with whatever HP's under there.
Nice car, 620 HP is impressive, but not from a blown 6.2.
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why not the LS2/LS7? 12:01PM (3/04/2008)
6.2L is not a measure of engine size, it is a measure of engine displacement. This engine (sans blower) is smaller and lighter than the BMW 5.0L V8 in the (previous) M5.
I agree the window is tacky.
tristan hipps 12:54PM (3/04/2008)
i bet that this 6.2 will make well over 620 hp. and will ge great mpg. this is not a hillbilly hotrod!!
Bruxell 1:43PM (3/04/2008)
Sorry, Enzos aren't "streetable?"
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Shipey 12:28PM (3/04/2008)
I don't think you're following me...
An engine of the same displacement, but N/A wouldn't shake a little more... I'm talking shaking your fillings out of your teeth, and having to scream over the noise. The high compression makes the engines hard to start, hard to idle, and very finicky. Which is fun! But it's not really something that will work in this application. Forced induction allows you to make the same power with all of the civility of a regular LS3 car.
The FXX is a race car. A multi-million dollar one at that. It doesn't need to be civil.
Also, the small block Chevy as it exists today, isn't really a small block at all. That distinction really only applied when there were two major engine designs in production. It was just an easy way to describe them. Even then they overlapped in displacements. (400ci small blocks and 396 big blocks) The B.O.P. motors were "mid-blocks" because they only had one basic engine design, which would be more akin to the current LS motors. they only call the LS motors small blocks because it's tradition.
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why not the LS2/LS7? 12:41PM (3/04/2008)
You can slice and dice my words all you want and it doesn't change my point. The LS7 (427) has the same external dimensions as the LS1 (350). That's what I'm talking about. Now you can go and call them both mid-blocks or whatever for all I care.
I completely disagree that you can't make a smooth large motor. What is this, the 60s? My 2.7 turbo (actually 2.65L) from Audi idles worse than a GM 4-banger or an LS1. And it's not smoother at speed than a V8 either.
I would love to have seen GM eek a few more revs out of the LS7, that wouldn't have made it rougher, it would have made it smoother. Yeah, it might not have made 620HP, but is anyone really going to turn their nose up at a V8 making 7500rpms and a "mere" 560HP?
Carlos 9:37PM (3/05/2008)
See the problem with just upping the rev limiter on the LS7 is a question of durability. Sure in the short term it won't have any effect, but what about 10 years down the road. That's why GM chose to use a supercharger instead of going for a high revving NA motor.
JIm 12:36PM (3/04/2008)
Like to complement the folks at GM for their inclusive attempt by allowing various groups a hand in fine-tuning the design of this very fast Corvette. Particularly noteworthy is their reaching out to the local inter-city eighth grade shop class for the detail work on the side vents and spoiler. Good job GM.
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Hiro11 12:40PM (3/04/2008)
Apparently, pushrods are still viable.
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Shipey 12:44PM (3/04/2008)
OK you win.
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