Corvette ZR-1 unveiled

I'd take the 599, sell it and buy a vette or two..
 
I'd take a Corvette over any ferarri any day of the week.
 
nist7 said:
Dyno graph comparing LS3, LS7, LS9, and the 8.4L V10 in the new Viper:

gmgraph.jpg
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As much as I like the Corvette, that is obviously propaganda. How can the viper's engine have that abnormal dip in torque like that? And even if it did, it would surely show up in the HP line as power is a direct function of torque and engine speed. Did the dyno operator accidentally lift his foot, realize it, then slam it to the floor again?
 
I don't think that graph is official or accurate. The Z06 is rated at 512hp in some markets and is a hand built engine, so HP numbers will vary. Same with the ZR-1 which isn't rated yet and no official numbers are released, which this graph conveniently doesn't show the ZR-1's peak horsepower.
 
starfox07 said:
As much as I like the Corvette, that is obviously propaganda. How can the viper's engine have that abnormal dip in torque like that? And even if it did, it would surely show up in the HP line as power is a direct function of torque and engine speed. Did the dyno operator accidentally lift his foot, realize it, then slam it to the floor again?
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It's not actually a dip, it flattens out for a bit, it can still build HP then. Keep in mind the new Viper engine has variable timing on the exhaust valves, and that could be right around the switch over.

If you look at the LS3 it has a similar issue in it's torque curve. Flat down low, then climbs. It's just coming "on cam".
 
TomCat said:
I don't think that graph is official or accurate. The Z06 is rated at 512hp in some markets and is a hand built engine, so HP numbers will vary. Same with the ZR-1 which isn't rated yet and no official numbers are released, which this graph conveniently doesn't show the ZR-1's peak horsepower.
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The engine, from what I've been led to believe is a little more undersquare than the LS7, as well as it having a positive displacement blower, so it shouldn't rev and make power as high, but this does not show that. I dont think the representation is accurate.:lol:

thedguy said:
It's not actually a dip, it flattens out for a bit, it can still build HP then. Keep in mind the new Viper engine has variable timing on the exhaust valves, and that could be right around the switch over.
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Yes I did forget about the variable timing. But not even Honda's vtec system which I'm fairly certain is more aggressive is that noticeable on a dyno sheet. Also I didn't notice (somehow) that the power line goes alot lower and is not shown, so there may be an indication of the dip a bit lower down that we can't see. I'm also curious to see how they made that system work on a ohv engine design. I wonder if its in the valvetrain or the cam where the lift/timing-change happens. I know ford uses phasers on the camshaft for the 4.6 to advance/retard timing, but that would invariably effect both intake and exhaust.
 
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starfox07 said:
Yes I did forget about the variable timing. But not even Honda's vtec system which I'm fairly certain is more aggressive is that noticeable on a dyno sheet. Also I didn't notice (somehow) that the power line goes alot lower and is not shown, so there may be an indication of the dip a bit lower down that we can't see. I'm also curious to see how they made that system work on a ohv engine design. I wonder if its in the valvetrain or the cam where the lift/timing-change happens. I know ford uses phasers on the camshaft for the 4.6 to advance/retard timing, but that would invariably effect both intake and exhaust.
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I just noticed, if you look again, the HP curve for the Viper engine doesn't actually start on the graph till AFTER the dip in torque at 3000rpms.

They have a special type of camshaft to make that work. the exhaust cams are slid over the main cam and can be moved independently of the entire shaft. Many reviews of the '08 viper have a info on how it works. There is also a review video in the videos section where it's talked about.
 
thedguy said:
I just noticed, if you look again, the HP curve for the Viper engine doesn't actually start on the graph till AFTER the dip in torque at 3000rpms.

They have a special type of camshaft to make that work. the exhaust cams are slid over the main cam and can be moved independently of the entire shaft. Many reviews of the '08 viper have a info on how it works. There is also a review video in the videos section where it's talked about.
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I like how the first three's torque and power all cross at 5250, as they should...but the standard LS3 crosses at 4700?? :blink:
 
starfox07 said:
I like how the first three's torque and power all cross at 5250, as they should...but the standard LS3 crosses at 4700?? :blink:
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You've just proven it's a fake graph. I didn't notice that. Not that having a curve for the LS9 isn't already hugely fishy.
 
starfox07 said:
As much as I like the Corvette, that is obviously propaganda. How can the viper's engine have that abnormal dip in torque like that? And even if it did, it would surely show up in the HP line as power is a direct function of torque and engine speed. Did the dyno operator accidentally lift his foot, realize it, then slam it to the floor again?
Click to expand...



All engines are different, there are so many variables that determine when power is produced it's incredable. Between the cam, heads, port velocity, combustion chamber, valve size, spark plug placement, timing etc...
 
0-60 Magazine shoot
[YOUTUBE]jhPFggwiLwk[/YOUTUBE]
 
that car sounds insane. it seems subtle but it just isnt. i thought they were going to do a 0-60 run tho :( oh well ill just have to wait for the next video to come out :D
 
I've never been a fan of Corvettes, until the C6 came out, now the ZR1 is trying to convert me from Ford to Chevy, :eek:

DO WANT, In blue, with silver wheels, and I'll take the plexiglas in the hood as well, something about that just screams badass to me. Don't know what though...
 
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MadCow809 said:
yeah, with the help of a S/C..... S2000 is N/A.
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By the same argument, Mercedes makes crappy engines. The AMG 55 only made 470-480 out of 5.5li with SC, and the 63 only has 500 out of 6.3li.
 
Ezbok58a said:
I've never been a fan of Corvettes, until the C6 came out, now the ZR1 is trying to convert me from Ford to Chevy, :eek:.
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Kind of hard to be a Ford fan these days when their idea of a performance car is a secretaries car :p

Oh look I haz a title!
 
That thing just screams menace! Is that a picture of a skull I see in the engine bay?? OMFG want one in black! And it better be damn loud!
 
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