If you guys want some real in-depth info on the LT1...
12-09-2012, 11:41 PM
#61
I'm really surprised that folks are taking this guy at face value.
My read is that he's an reasonably intelligent and knowledgeable troll.
There is NO WAY he is sanctioned by Chevy/GM to be posting the things he is posting. They control their PR image much too carefully to allow anyone to write in the fashion this guy is.
Secondly, he writes to confuse, not to educate.
Third, a considerable amount of his data is contradictory.
He's gone on and on about how the ECU is now a hypervisor controlled second OS and totally uncrackable (or something similar to this).
However, here's the rub...
You write a hypervisor to *share* a single hardware resource.
You're basically pretending a single piece of hardware is two (or more) things.
What you give up when you do that is total control of the hardware. Your private hardware is now shared, and you can't always be certain when your next turn is coming up.
But then he says that the reason they did this was to keep the thing secure, because we'll all die horribly if we change the fuel tables, because the timing of them is all so critical.
Well, if they're that critical, you need to lock down all the timing. Which means you... can't be shared. If that injector needs to go NOW, you can't wait for the hypervisor to give you your turn on the hardware.
Okay, its not COMPLETELY impossible, if you had enough smart guys and enough time and you got lucky, you could kinda sorta cobble something together and make it work.
In the same way that if you put enough smart guys together they could make a dump truck lap the Nurburgring in competitive time.
My read is that he's an reasonably intelligent and knowledgeable troll.
There is NO WAY he is sanctioned by Chevy/GM to be posting the things he is posting. They control their PR image much too carefully to allow anyone to write in the fashion this guy is.
Secondly, he writes to confuse, not to educate.
Third, a considerable amount of his data is contradictory.
He's gone on and on about how the ECU is now a hypervisor controlled second OS and totally uncrackable (or something similar to this).
However, here's the rub...
You write a hypervisor to *share* a single hardware resource.
You're basically pretending a single piece of hardware is two (or more) things.
What you give up when you do that is total control of the hardware. Your private hardware is now shared, and you can't always be certain when your next turn is coming up.
But then he says that the reason they did this was to keep the thing secure, because we'll all die horribly if we change the fuel tables, because the timing of them is all so critical.
Well, if they're that critical, you need to lock down all the timing. Which means you... can't be shared. If that injector needs to go NOW, you can't wait for the hypervisor to give you your turn on the hardware.
Okay, its not COMPLETELY impossible, if you had enough smart guys and enough time and you got lucky, you could kinda sorta cobble something together and make it work.
In the same way that if you put enough smart guys together they could make a dump truck lap the Nurburgring in competitive time.
I read all of his posts, and the one post that raised the greatest question for me was how much additional hp they will achieve in a N/A motor with E-85. In a FI setup, OK, I completely understand that. You can run higher boost due to the higher octane level of E-85. But in a N/A setup, I’m not sure. He talked about increasing the duration of lift (I still don’t know how they accomplish that, but that is not to say that I can disprove that statement) and allow more air into the chamber, which is completely logical. E-85 can take higher dynamic compression than 93 octane before detonation becomes an issue. But it only makes sense if you really can control the duration (as opposed to phase) using VVT. I think I remember reading somewhere that certain engines can vary lift, I just don’t know how they can vary duration, especially in a push rod setup. Maybe this is the great technological advance in the LT1, I don’t know.
Anyway, for the time being I’ll assume that he is legit. We should know for sure on Jan. 13.
Last edited by C8forT; 12-09-2012 at 11:46 PM.
12-10-2012, 12:02 AM
#63
Team Owner
I agree that the LT1 likely will be the best V-8 platform. I think the LT1 will lay smack down on the LS3, and the LS7 when using E-85. I think its "big brother" will be the one to lay smack down on the LS7 (on 93 octane), the LSA and the LS9.
His responses got me really excited too. It is nice to get such detailed information from an insider.
His responses got me really excited too. It is nice to get such detailed information from an insider.
With all of the improvements, the C7 looks like it will be a great daily driver and road course car. I think, however, traction in first gear is going to be an issue with the increased torque, and the TCU will kick in and suck out much of that torque when launching from a dead stop. That is a shame. It would be really great to use ALL of the torque/hp out of the hole, wich means greatly improving rear wheel traction. Hopefully they have addressed this.
12-10-2012, 12:02 AM
#64
I'm really surprised that folks are taking this guy at face value.
You write a hypervisor to *share* a single hardware resource.
You're basically pretending a single piece of hardware is two (or more) things.
What you give up when you do that is total control of the hardware. Your private hardware is now shared, and you can't always be certain when your next turn is coming up.
But then he says that the reason they did this was to keep the thing secure, because we'll all die horribly if we change the fuel tables, because the timing of them is all so critical.
Well, if they're that critical, you need to lock down all the timing. Which means you... can't be shared. If that injector needs to go NOW, you can't wait for the hypervisor to give you your turn on the hardware.
You write a hypervisor to *share* a single hardware resource.
You're basically pretending a single piece of hardware is two (or more) things.
What you give up when you do that is total control of the hardware. Your private hardware is now shared, and you can't always be certain when your next turn is coming up.
But then he says that the reason they did this was to keep the thing secure, because we'll all die horribly if we change the fuel tables, because the timing of them is all so critical.
Well, if they're that critical, you need to lock down all the timing. Which means you... can't be shared. If that injector needs to go NOW, you can't wait for the hypervisor to give you your turn on the hardware.
12-10-2012, 12:47 AM
#65
Team Owner
Member Since: Jul 2003
Location: Charleston/Lake Villa IL
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A more specific response to this portion of the post. It may be a multi-core processor, and multi-threaded. An off the shelf $100 processor (retail) made today by AMD or Intel would be way more than fast enough to handle all of the requirements without anywhere near enough lag time to cause an issue, even with virtualization. Remember, this thing does not need to run Windows, etc. It's like running a couple of DOS sessions with a miniscule version of dBase on a modern processor. (OK, virtualization adds some complexity). But processor performance will not be an issue.
12-10-2012, 01:12 AM
#66
Advanced
This may be a bit off but I have a copy of Desktop Dyno 2003.
I have plugged in as close as my software will allow the engine specs for this new LT1 and this is what it comes up with:
RPM HP TQ
2000 149 391
2500 197 414
3000 255 446
3500 324 486
4000 382 501
4500 435 508
5000 482 506
5500 509 486
6000 524 458
6500 521 420
7000 506 380
Torque curve shows as described to the LS7. As with my 434sbc a good factor in making power is the upped compression ratio and larger valves. These numbers are off I'm sure but it does at least help show me where the power levels are to come in at.
I have plugged in as close as my software will allow the engine specs for this new LT1 and this is what it comes up with:
RPM HP TQ
2000 149 391
2500 197 414
3000 255 446
3500 324 486
4000 382 501
4500 435 508
5000 482 506
5500 509 486
6000 524 458
6500 521 420
7000 506 380
Torque curve shows as described to the LS7. As with my 434sbc a good factor in making power is the upped compression ratio and larger valves. These numbers are off I'm sure but it does at least help show me where the power levels are to come in at.
Last edited by NewmanC6; 12-10-2012 at 01:13 AM. Reason: typo
12-10-2012, 01:47 AM
#67
It gets to me that the GT-R and 911 Turbo are faster 0-60 and 1-4 mi. than the ZR1, with more weight and less hp. The GT-R now is under 3.0 sec. 0-60. I understand it is because they are AWD, and I don't want those cars, but I would like the C7 to close the gap a little closer. The Ferarri 458 is somewhere around 3.0 sec. 0-60, and is not AWD. The C7 will be a fraction of its cost, and I don't expect it to match that, but if they can take some of that technology and incorporate it into the C7, that would be great.
Last edited by C8forT; 12-10-2012 at 01:51 AM.
12-10-2012, 02:18 AM
#69
^^^
At least she's somewhat cute.
At least she's somewhat cute.
12-10-2012, 02:50 AM
#70
Melting Slicks
I agree that the LT1 likely will be the best V-8 platform. I think the LT1 will lay smack down on the LS3, and the LS7 when using E-85. I think its "big brother" will be the one to lay smack down on the LS7 (on 93 octane), the LSA and the LS9.
His responses got me really excited too. It is nice to get such detailed information from an insider.
His responses got me really excited too. It is nice to get such detailed information from an insider.
12-10-2012, 05:40 AM
#71
I read all of his posts, and the one post that raised the greatest question for me was how much additional hp they will achieve in a N/A motor with E-85. In a FI setup, OK, I completely understand that. You can run higher boost due to the higher octane level of E-85. But in a N/A setup, I’m not sure. He talked about increasing the duration of lift (I still don’t know how they accomplish that, but that is not to say that I can disprove that statement) and allow more air into the chamber, which is completely logical. E-85 can take higher dynamic compression than 93 octane before detonation becomes an issue. But it only makes sense if you really can control the duration (as opposed to phase) using VVT. I think I remember reading somewhere that certain engines can vary lift, I just don’t know how they can vary duration, especially in a push rod setup. Maybe this is the great technological advance in the LT1, I don’t know.
Since the LT1 already can deactivate cylinders, which I presume part of that means deactivating lifters on the effected cylinders, they can dynamically control the lifters. So, in the 93 octane mode, the lifters can be controlled to reduce the duration of valve opening with respect to the cam lobe duration. When higher octane fuel is detected, the lifters can be controlled to increase the duration of valve opening closer to that of the actual cam lobe duration.
So, with lower octane fuels, the duration of the valve opening (at least the intake valve) is lower than the actual duration of the cam. When higher octane fuels are detected, the duration of the valve opening is closer to the actual duration of the cam.
This is mere speculation on my part, so any input is welcomed.
12-10-2012, 10:25 AM
#72
Melting Slicks
Thread Starter
12-10-2012, 11:14 AM
#74
Team Owner
I have been pondering over the issue of variable cam duration. Here is my hypothesis:
Since the LT1 already can deactivate cylinders, which I presume part of that means deactivating lifters on the effected cylinders, they can dynamically control the lifters. So, in the 93 octane mode, the lifters can be controlled to reduce the duration of valve opening with respect to the cam lobe duration. When higher octane fuel is detected, the lifters can be controlled to increase the duration of valve opening closer to that of the actual cam lobe duration.
So, with lower octane fuels, the duration of the valve opening (at least the intake valve) is lower than the actual duration of the cam. When higher octane fuels are detected, the duration of the valve opening is closer to the actual duration of the cam.
This is mere speculation on my part, so any input is welcomed.
Since the LT1 already can deactivate cylinders, which I presume part of that means deactivating lifters on the effected cylinders, they can dynamically control the lifters. So, in the 93 octane mode, the lifters can be controlled to reduce the duration of valve opening with respect to the cam lobe duration. When higher octane fuel is detected, the lifters can be controlled to increase the duration of valve opening closer to that of the actual cam lobe duration.
So, with lower octane fuels, the duration of the valve opening (at least the intake valve) is lower than the actual duration of the cam. When higher octane fuels are detected, the duration of the valve opening is closer to the actual duration of the cam.
This is mere speculation on my part, so any input is welcomed.
When running on 8 cylinders the spring loaded shot pin is extended and locks the the telescoping lifter into a single piece. In 4 cylinder mode,the shot pin is retracted using pressuized engine oil, disconnecting the two parts of the lifer. The outer shell of the lifer follows the cam lobe, but the inner part of the lifter does not transmit that motion to the push rod.
Last edited by JoesC5; 12-10-2012 at 11:17 AM.
12-10-2012, 11:49 AM
#75
Burning Brakes
I.e, Look at the vicious cat and mouse game constantly going on between Apple and the hacker community. A lot of time and money goes into making it more difficult to hack their software then Inevitably, days or weeks after a new iOS is released someone somewhere has found another exploit.
12-19-2012, 02:17 PM
#76
A few more tidbits posted by Bigg_Gunz in the LS1Tech thread:
"I can 100% assure you the "HINTS" are further back in the thread. The heads design and layout are a give away for what this engine true intentions are and you would definitely want to save your money for the replacement of the C6 z06. As that engine is down RIGHT BRUTAL."
"Big Brother doesn't like the input shaft in the current transmissions as it keeps busting it, not only 1st gear but 2nd as well. In my team... dialing back the torque for the sake of transmission torque capacity is just a deal breaker. We have a clear mission in mind for what is to come."
"What I can tell you is that....We are in the HUNT to take a few titles from HYPER CARS."
"I can 100% assure you the "HINTS" are further back in the thread. The heads design and layout are a give away for what this engine true intentions are and you would definitely want to save your money for the replacement of the C6 z06. As that engine is down RIGHT BRUTAL."
"Big Brother doesn't like the input shaft in the current transmissions as it keeps busting it, not only 1st gear but 2nd as well. In my team... dialing back the torque for the sake of transmission torque capacity is just a deal breaker. We have a clear mission in mind for what is to come."
"What I can tell you is that....We are in the HUNT to take a few titles from HYPER CARS."
12-19-2012, 09:27 PM
#78
Another tidbit:
I asked in the LSTtech forum: "Is GM doing anything to improve rear wheel traction on the C7 to improve 0-60 performance? Will we see some rear weight bias?" Bigg_Gunz answered "yes."
This is significant... Not only will it improve acceleration from a dead stop (e.g., 0-60, 1/4 mi., etc.), it will also improve road track performance when accellerating out of a turn... I don't have the link, but I recall one of the Corvette Racing drivers commenting that the 911 had an advantage accellerating out of turns due to the additional rear traction provided by its rear weight bias. This was, in part, my motivation for asking the question.
I asked in the LSTtech forum: "Is GM doing anything to improve rear wheel traction on the C7 to improve 0-60 performance? Will we see some rear weight bias?" Bigg_Gunz answered "yes."
This is significant... Not only will it improve acceleration from a dead stop (e.g., 0-60, 1/4 mi., etc.), it will also improve road track performance when accellerating out of a turn... I don't have the link, but I recall one of the Corvette Racing drivers commenting that the 911 had an advantage accellerating out of turns due to the additional rear traction provided by its rear weight bias. This was, in part, my motivation for asking the question.