A little bit of inside info on the 'possible' C7 ZR1
12-11-2012, 02:52 PM
#21
Le Mans Master
Thread Starter
I'm much more impressed with the DOHC engine used in the Mercedes SLS AMG over the Ferrari. How much does the Ferrari engine weigh? The LT1 weighs 465 pounds, and the 6.3L Mercedes engine only weighs 455 pounds. The Mercedes has 1.28 HP/lb. That is a much more usefull measurement then HP/L.
The Mercedes has 583 horspower at 6,800 RPM and 479 lbs-ft at 4750 RPM. Compare that to the 398 lbs-ft with the Ferrari. No need to wind the hell out of the Mercedes to get it going.
Of course, neither the Ferrari or the Mercedes is going to get by without the purchaser paying a gas guzzler tax and the manufacturer paying the EPA a fine for the crappy gas mileage they get.
Wouldn't surprize me though, if the supercharged version of the LT1 in the C7, even with the addtiional weight of the supercharger, etc, comes in with the car weight per horsepower lower then the the Ferrari or Mercedes SLS AMG , and blows the Ferrari and the Mercedes out of the water with the supercharged C7's gas mileage above 25 MPG highway. The Mercedes only gets 13 city and 19 highway.
The Mercedes has 583 horspower at 6,800 RPM and 479 lbs-ft at 4750 RPM. Compare that to the 398 lbs-ft with the Ferrari. No need to wind the hell out of the Mercedes to get it going.
Of course, neither the Ferrari or the Mercedes is going to get by without the purchaser paying a gas guzzler tax and the manufacturer paying the EPA a fine for the crappy gas mileage they get.
Wouldn't surprize me though, if the supercharged version of the LT1 in the C7, even with the addtiional weight of the supercharger, etc, comes in with the car weight per horsepower lower then the the Ferrari or Mercedes SLS AMG , and blows the Ferrari and the Mercedes out of the water with the supercharged C7's gas mileage above 25 MPG highway. The Mercedes only gets 13 city and 19 highway.
RJ-92, if you're right on the engine geometry not being ideal for an 8,000rpm+ motor, then that probably kills 100% the possibility of an NA motor. Of course, GM may know something we don't on technology for the LT1 platform. I guess we will know for sure in a few years.
12-11-2012, 03:00 PM
#22
Team Owner
I expect the ZR1 to have turbos. I have had a few turbos going back 30 years. I currently have a BMW 550 with a 4.4 liter twin turbo - 400hp, 450 lb ft torque. The car has virtually zero lag, an unbelievable torque spread and I have averaged 27.5 mpg on three long trips in the car.
Before I got this car I always preferred the naturally aspirated route. But I can't really say that now that I have the 550.
Before I got this car I always preferred the naturally aspirated route. But I can't really say that now that I have the 550.
12-11-2012, 03:13 PM
#23
Instructor
Member Since: Jun 2012
Location: Alabama
Posts: 249
Likes: 0
Received 0 Likes
on
0 Posts
Ferrari does make one hell of an engine, but after 30K miles? Check on the cost of a refresh for one of the current F car power plants. GM will not be putting something like that on the market. Whatever they do use will have to be 100K reliable, and as has been mentioned be able to survive some HPDE time.
Also the DCT's are heavy. Unless they can get the weight down, way down, I don't see one in our near future. I think the earlier poster was right that GM will improve the product by making it lighter, stronger, reliable, etc not necessarily by huge HP increases. Depending on the track one of the fastest production cars in the world is Z06/Z07 package. Has fastest slalom speed tested by mototrend right now. Add some HP's, lighten it up , other improvements, and there you go. F car killer for way less than half the money and a 100K power train warranty. These are exciting times for car enthusiasts.
Also the DCT's are heavy. Unless they can get the weight down, way down, I don't see one in our near future. I think the earlier poster was right that GM will improve the product by making it lighter, stronger, reliable, etc not necessarily by huge HP increases. Depending on the track one of the fastest production cars in the world is Z06/Z07 package. Has fastest slalom speed tested by mototrend right now. Add some HP's, lighten it up , other improvements, and there you go. F car killer for way less than half the money and a 100K power train warranty. These are exciting times for car enthusiasts.
12-11-2012, 03:15 PM
#24
I expect the ZR1 to have turbos. I have had a few turbos going back 30 years. I currently have a BMW 550 with a 4.4 liter twin turbo - 400hp, 450 lb ft torque. The car has virtually zero lag, an unbelievable torque spread and I have averaged 27.5 mpg on three long trips in the car.
Before I got this car I always preferred the naturally aspirated route. But I can't really say that now that I have the 550.
Before I got this car I always preferred the naturally aspirated route. But I can't really say that now that I have the 550.
GM is no stranger to turbos and I'm sure someone has already cooked up plans for a TT LTx motor. They've got the turbo 4s already and the TT V6 should come out later this week in the Silverado.
12-11-2012, 03:49 PM
#25
Le Mans Master
Thread Starter
Yeah, the N54 motor in my 335 is great aside from the normal BMW reliability problems. Great low end torque, wide powerband, great highway gas mileage, quiet, and smooth.
GM is no stranger to turbos and I'm sure someone has already cooked up plans for a TT LTx motor. They've got the turbo 4s already and the TT V6 should come out later this week in the Silverado.
GM is no stranger to turbos and I'm sure someone has already cooked up plans for a TT LTx motor. They've got the turbo 4s already and the TT V6 should come out later this week in the Silverado.
Okay, so we all agree the next ZR1 engine is going to be a 5.5L twin turbo LT9 making 680-700hp and have about 650lb/ft of torque while also getting 25+mpg. Sounds good. Where do I sign?
12-11-2012, 04:46 PM
#26
Drifting
The LT1 will be somewhere near 465-480hp. Couple that with very good hiway mpg and a car weighing less then 3100lbs and you have 85% of the potential customers covered. Give it a few years for additional power tweaks and you will be close to 500hp.
Then the performance variant of the Z06 with more displacement and 620-650hp to slap the Viper and GT500 silly and you have now covered the next 10% of vette owners.
One more version, with the ZR1 which will defintly be FI and you have a 725-750hp version to run with any exotic along with the accompanying weight reduction and improved handling and braking on all models and 3-4 years from now all the naysayers will have to find something else to whine about. And the last 5% have what they wanted.
It won't be because the general has not got the weight to power ratio equation worked out that folks ain't buying vettes.
Then the performance variant of the Z06 with more displacement and 620-650hp to slap the Viper and GT500 silly and you have now covered the next 10% of vette owners.
One more version, with the ZR1 which will defintly be FI and you have a 725-750hp version to run with any exotic along with the accompanying weight reduction and improved handling and braking on all models and 3-4 years from now all the naysayers will have to find something else to whine about. And the last 5% have what they wanted.
It won't be because the general has not got the weight to power ratio equation worked out that folks ain't buying vettes.
12-11-2012, 04:56 PM
#27
Race Director
Member Since: Oct 2000
Location: Deal's Gap 2004 NCM Motorsports track supporter
Posts: 13,915
Received 1,103 Likes
on
717 Posts
....... The engine won't heat up like my C6 ZR1 at the track, lighter weight, so better chance for the brakes to work longer, etc. The Corvette racecars GM uses are naturally aspirated 5.5L engines. Hmmmm......
The more I think about it, the more innovative and exciting a nice NA engine would on the ZR1 with the associated weight reduction, better cooling, etc. As a C6 ZR1 owner, I wouldn't care at all if the engine horsepower was actually a little less than my current LS9 if I got all the other benefits mentioned above.
Give me light weight and better balance. My track prepared C5Z (at a 3200#'s or so with no driver) gets hot in the driveline with acceleration, hot fluids and hot brakes when stopping. Tires wear quicker, get greasy quicker and don't cycle as many times as they would if car were lighter. Even with 2pc. rotors and DTC 70's with a passenger I am pushing 3700#'s and stopping distances get iffy real quick.
12-11-2012, 10:47 PM
#29
Instructor
I have a feeling the C7 will have a motor that is forced induction 6.2L that may happen to be called the LT4 and it may have 660hp....I dont know but just my thoughts
12-11-2012, 10:52 PM
#30
Instructor
Huh? More info on this TT V6 in the Silverado? I had heard the ATS-V was going to get a twin turbo V6 in the upper 400hp range (of course, not official). I guess it makes sense to have a GM response to the Ecoboost 3.5L V6 Ford is putting in the F-150.
Okay, so we all agree the next ZR1 engine is going to be a 5.5L twin turbo LT9 making 680-700hp and have about 650lb/ft of torque while also getting 25+mpg. Sounds good. Where do I sign?
Okay, so we all agree the next ZR1 engine is going to be a 5.5L twin turbo LT9 making 680-700hp and have about 650lb/ft of torque while also getting 25+mpg. Sounds good. Where do I sign?
12-12-2012, 02:53 AM
#31
Melting Slicks
My 2 cents -
DOHC will not happen due to the hood line. The DOHC option would be too tall to fit in the engine bay, especially if the car is slightly smaller than the C6 as has been suggested. It is also not congruent with GM's history of SBC motors - the Z06/ZR1 or whatever they come out with will share a great deal with the LT1.
FI works and it's the simplest solution. The C6 ZR1 could have had 700 HP with more tweaking from the factory. Now with DI and a cam phaser, GM can easily get another 50-60 HP more from the same configuration (conservative tune) using a TVS supercharger and 6.2 liter motor. Turbos would be nice too - less issue with heat soak.
I hope they bring the Z06 back with a successor to the LS7. Imagine a 427 with DI and cam phaser!!! 550-575 HP with gobs of low end torque due to the cam phaser. If they can pull this off and make it weight less than the 06-08 Z06's, that would be a killer combination.
DOHC will not happen due to the hood line. The DOHC option would be too tall to fit in the engine bay, especially if the car is slightly smaller than the C6 as has been suggested. It is also not congruent with GM's history of SBC motors - the Z06/ZR1 or whatever they come out with will share a great deal with the LT1.
FI works and it's the simplest solution. The C6 ZR1 could have had 700 HP with more tweaking from the factory. Now with DI and a cam phaser, GM can easily get another 50-60 HP more from the same configuration (conservative tune) using a TVS supercharger and 6.2 liter motor. Turbos would be nice too - less issue with heat soak.
I hope they bring the Z06 back with a successor to the LS7. Imagine a 427 with DI and cam phaser!!! 550-575 HP with gobs of low end torque due to the cam phaser. If they can pull this off and make it weight less than the 06-08 Z06's, that would be a killer combination.
12-12-2012, 12:29 PM
#32
Tech Contributor
Member Since: Oct 1999
Location: Charlotte, NC (formerly Endicott, NY)
Posts: 40,094
Received 8,928 Likes
on
5,333 Posts
Bill
12-12-2012, 12:46 PM
#33
The LT1 will be somewhere near 465-480hp. Couple that with very good hiway mpg and a car weighing less then 3100lbs and you have 85% of the potential customers covered. Give it a few years for additional power tweaks and you will be close to 500hp.
Then the performance variant of the Z06 with more displacement and 620-650hp to slap the Viper and GT500 silly and you have now covered the next 10% of vette owners.
One more version, with the ZR1 which will defintly be FI and you have a 725-750hp version to run with any exotic along with the accompanying weight reduction and improved handling and braking on all models and 3-4 years from now all the naysayers will have to find something else to whine about. And the last 5% have what they wanted.
It won't be because the general has not got the weight to power ratio equation worked out that folks ain't buying vettes.
Then the performance variant of the Z06 with more displacement and 620-650hp to slap the Viper and GT500 silly and you have now covered the next 10% of vette owners.
One more version, with the ZR1 which will defintly be FI and you have a 725-750hp version to run with any exotic along with the accompanying weight reduction and improved handling and braking on all models and 3-4 years from now all the naysayers will have to find something else to whine about. And the last 5% have what they wanted.
It won't be because the general has not got the weight to power ratio equation worked out that folks ain't buying vettes.
12-12-2012, 01:19 PM
#34
Race Director
Jimmy
12-14-2012, 08:19 PM
#35
Le Mans Master
You forgot your E85!
This isn't as juicy as the other info on the brakes and the person I spoke with was very evasive about any details at all on the C7 ZR1, but I did get a little bit of info from him/her.
-There is not yet a definitive green light on the C7 ZR1 (or equivalent), but it's highly likely for obvious reasons (success of the C6 ZR1).
-There are only two prototypes built at this time of what could 'potentially' be the C7 ZR1.
-They haven't decided on the engine, but I asked some very pointed questions and I looked for nonverbal cues on 'his/her' face. I asked whether the engine was going to be forced induction or a very high revving NA engine and I got a very slight smile. I don't know how to read that. He/she insinuated final decisions haven't been made which led me to believe they are still considering BOTH avenues. I pressed and said I would personally think it would be quite hard to achieve horsepower/durability targets with a naturally aspirated engine and the guy went on a very small tangent and said in the future, it's not going to always be about horsepower, but weight, efficiency, and other factors while still achieving huge performance targets.
I then asked since the LT1 is a clean sheet and the issues they have with the LS-based engine and the turbo C6 ZR1 mules burning to the ground, I would think GM could have factored turbocharged application into the LT1 architecture. The 'person' at that point just gave me a blank look and didn't say anything. So, again not sure how to read that?!?!
-3rd generation magnetic suspension is going to have a much broader range between comfort mode and sport mode. So, get ready for a truly Cadillac comfy ride in tour mode and rock and roll performance mode at the other end.
-dual clutch transmission- one 'person' said it's 8-speed normal automatic at this point and dual-clutch is on the shelf for now. I asked another person who seemed to be more knowledgeable 'person' about how awesome it would be to have a dual-clutch transmission at least in the Z06 and ZR1 equivalents. He/she agreed that it would be nice, but didn't give anything else away, so I don't know. I think GM Powertrain is really working hard on it, but the base model Vette is going to have a 7-speed manual and a 'normal' 8-speed automatic. I don't think that is new info.
That's about all the info I got. Certainly interesting stuff coming up soon though and it's a GREAT time to be a Corvette fan.
-There is not yet a definitive green light on the C7 ZR1 (or equivalent), but it's highly likely for obvious reasons (success of the C6 ZR1).
-There are only two prototypes built at this time of what could 'potentially' be the C7 ZR1.
-They haven't decided on the engine, but I asked some very pointed questions and I looked for nonverbal cues on 'his/her' face. I asked whether the engine was going to be forced induction or a very high revving NA engine and I got a very slight smile. I don't know how to read that. He/she insinuated final decisions haven't been made which led me to believe they are still considering BOTH avenues. I pressed and said I would personally think it would be quite hard to achieve horsepower/durability targets with a naturally aspirated engine and the guy went on a very small tangent and said in the future, it's not going to always be about horsepower, but weight, efficiency, and other factors while still achieving huge performance targets.
I then asked since the LT1 is a clean sheet and the issues they have with the LS-based engine and the turbo C6 ZR1 mules burning to the ground, I would think GM could have factored turbocharged application into the LT1 architecture. The 'person' at that point just gave me a blank look and didn't say anything. So, again not sure how to read that?!?!
-3rd generation magnetic suspension is going to have a much broader range between comfort mode and sport mode. So, get ready for a truly Cadillac comfy ride in tour mode and rock and roll performance mode at the other end.
-dual clutch transmission- one 'person' said it's 8-speed normal automatic at this point and dual-clutch is on the shelf for now. I asked another person who seemed to be more knowledgeable 'person' about how awesome it would be to have a dual-clutch transmission at least in the Z06 and ZR1 equivalents. He/she agreed that it would be nice, but didn't give anything else away, so I don't know. I think GM Powertrain is really working hard on it, but the base model Vette is going to have a 7-speed manual and a 'normal' 8-speed automatic. I don't think that is new info.
That's about all the info I got. Certainly interesting stuff coming up soon though and it's a GREAT time to be a Corvette fan.
Turbos, DI, E85, and I bet your selling!
12-14-2012, 09:59 PM
#37
Safety Car
My 2 cents -
DOHC will not happen due to the hood line. The DOHC option would be too tall to fit in the engine bay, especially if the car is slightly smaller than the C6 as has been suggested. It is also not congruent with GM's history of SBC motors - the Z06/ZR1 or whatever they come out with will share a great deal with the LT1.
FI works and it's the simplest solution. The C6 ZR1 could have had 700 HP with more tweaking from the factory. Now with DI and a cam phaser, GM can easily get another 50-60 HP more from the same configuration (conservative tune) using a TVS supercharger and 6.2 liter motor. Turbos would be nice too - less issue with heat soak.
I hope they bring the Z06 back with a successor to the LS7. Imagine a 427 with DI and cam phaser!!! 550-575 HP with gobs of low end torque due to the cam phaser. If they can pull this off and make it weight less than the 06-08 Z06's, that would be a killer combination.
DOHC will not happen due to the hood line. The DOHC option would be too tall to fit in the engine bay, especially if the car is slightly smaller than the C6 as has been suggested. It is also not congruent with GM's history of SBC motors - the Z06/ZR1 or whatever they come out with will share a great deal with the LT1.
FI works and it's the simplest solution. The C6 ZR1 could have had 700 HP with more tweaking from the factory. Now with DI and a cam phaser, GM can easily get another 50-60 HP more from the same configuration (conservative tune) using a TVS supercharger and 6.2 liter motor. Turbos would be nice too - less issue with heat soak.
I hope they bring the Z06 back with a successor to the LS7. Imagine a 427 with DI and cam phaser!!! 550-575 HP with gobs of low end torque due to the cam phaser. If they can pull this off and make it weight less than the 06-08 Z06's, that would be a killer combination.
To get from 640hp to 700hp the LS9 has to get a very extreme pulley. There are diminishing returns to raising the boost and it gets incrementally less safe to do so and give a warranty.
Anyway, given the info that is out there my guess is that there will be three versions of this motor, all pushrod:
6.2L 475 hp N/A with VVT for the base
7L bored out LT1 575hp N/A with dual VVT for a Z06 like car
6.2L 750hp Supercharged dual VVT for a ZR1 like car
That's what I gather with the info we have out there and a bit of educated guessing. Add to that 15% increase in HP on E85 for all three.
Last edited by SBC_and_a_stick; 12-14-2012 at 10:01 PM.
12-14-2012, 11:27 PM
#38
Racer
I think for most of the C7's run you will have 2 models the base and a higher performance version maybe and a big maybe you will have 3 engine models like the current C6 depending on the market. The C6 had nearly every special model known to corvette. They brought in both performance model monikers from the C4(ZR-1), GS and the C5(ZO6) all at once you had the base, GS, ZO6, ZR1. Some of it was demand from consumers but I also think some decisions may have been made because of the economic downturn they knew that they had to keep the C6 alive a little longer than planned at least that's what I've heard from a few members here. We will see though because the market is certainly filled with way more high performance cars than in the C5's run. I just hope the economy and market will support multiple high performance models of the C7.
12-16-2012, 10:09 AM
#39
Le Mans Master
Gm has gone backwards on the Automatic since the 4L80e.
12-18-2012, 03:11 AM
#40
Drifting
If the 7L is dead... i just wish that they give the BORE size a healthy 4.125 so that we with the aftermarket can build easily and cheaply a 427 engine like the ls7.
Thank you very much.
Thank you very much.