Why is redline the same on ZR1 - no AFM?
05-05-2018, 05:47 PM
#1
Melting Slicks
Thread Starter
Why is redline the same on ZR1 - no AFM?
Why isn’t the redline higher on the ZR1? Piston speeds are lower than a Z06 from 12 years ago.
I’ve read over and over the reason for the 6500 RPM redline is that the AFM valve train couldn’t handle the high speed. Well, the AFM is gone, now why?
And why no new tires? Just a wider front wheel, why not stickier rubber? It seems like Michelin adds another spec for Porsche on the the Sport Cup 2 whenever a newer iteration of the 911 comes out.
Is this a halo car or another parts bin car?
I’ve read over and over the reason for the 6500 RPM redline is that the AFM valve train couldn’t handle the high speed. Well, the AFM is gone, now why?
And why no new tires? Just a wider front wheel, why not stickier rubber? It seems like Michelin adds another spec for Porsche on the the Sport Cup 2 whenever a newer iteration of the 911 comes out.
Is this a halo car or another parts bin car?
05-05-2018, 07:06 PM
#4
Melting Slicks
Thread Starter
05-05-2018, 07:06 PM
#5
Instructor
Higher RPM would likely result in more power, this engine doesn't need to be spun to the moon to make power. Its not a GT350 or Ferrari or any of those other 8000+RPM motors, lower MPG and higher power would likely be results from spinning higher and GM wants to keep the numbers within reason im sure.
05-05-2018, 07:07 PM
#6
Melting Slicks
Thread Starter
05-05-2018, 07:08 PM
#7
Instructor
Well they are a business, so naturally they want to keep their options open next gen for more power as will happen. Im sure it wouldn't be hard to have made a legit 850hp ZR1 that's reliable but then the C8Z will have to follow closely. I think the ZR1 is pretty legit for where its at,
05-05-2018, 07:09 PM
#8
Melting Slicks
Thread Starter
Higher RPM would likely result in more power, this engine doesn't need to be spun to the moon to make power. Its not a GT350 or Ferrari or any of those other 8000+RPM motors, lower MPG and higher power would likely be results from spinning higher and GM wants to keep the numbers within reason im sure.
05-05-2018, 07:11 PM
#9
Melting Slicks
Thread Starter
Well they are a business, so naturally they want to keep their options open next gen for more power as will happen. Im sure it wouldn't be hard to have made a legit 850hp ZR1 that's reliable but then the C8Z will have to follow closely. I think the ZR1 is pretty legit for where its at,
Why can't we get MPSS with the big wing? I'd wager a high percentage of customers would want this.
05-05-2018, 07:23 PM
#10
Instructor
Yeah they have to do what makes sense to them first then us, I can think of a million different things i would like too but this is at the end a production car and not a specialty hand made $300-500k car which will allow u a lot more choices.
05-05-2018, 07:27 PM
#12
Melting Slicks
Thread Starter
The car is now $140K. At what price does the excuse that it's a production car stop? $200K?
Higher redline would also allow more flexibility holding gears on the track. It's more than just power.
Higher redline would also allow more flexibility holding gears on the track. It's more than just power.
05-05-2018, 07:31 PM
#13
Team Owner
While the AFM lifters were a factor in limiting the engine's RPM to 6,500 on the LT1 and the LT4, the weight of the rods also come into play. The 7,000 RPM LS7 has lightweight forged titanium rods, whereas the LT5 has heavier forged powered metal rods. Titanium rods are very expensive.
Last edited by JoesC5; 05-05-2018 at 07:34 PM.
05-05-2018, 07:37 PM
#14
Melting Slicks
Thread Starter
While the AFM lifters were a factor in limiting the engine's RPM to 6,500 on the LT1 and the LT4, the weight of the rods also come into play. The 7,000 RPM LS7 has lightweight forged titanium rods, whereas the LT5 has heavier forged powered metal rods. Titanium rods are very expensive.
Or did the C6 ZR1 have titanium rods?
Last edited by fatsport; 05-05-2018 at 07:43 PM.
05-05-2018, 07:52 PM
#15
Team Owner
The C7 LT4 has titanium intake valves.
Last edited by JoesC5; 05-05-2018 at 07:56 PM.
05-05-2018, 07:53 PM
#16
Drifting
I agree, with this better valve training, I would have thought they would have raised the redline to 7,000rpm.
The current rods are fine for the current stroke.
Leaving the power band as it currently is and raising the redline would make for a faster accelerating car.
The current rods are fine for the current stroke.
Leaving the power band as it currently is and raising the redline would make for a faster accelerating car.
05-05-2018, 07:57 PM
#17
If you can make 755hp at 6500 revs, there is no need to rev higher.
The GT3 revs to 9k becuase it has to to make the power.
The manual does nearly 100 in 2nd, how much gearing flexibility do you need. You can’t look at just max engine speed to assess gearing flexibility. You have to look at the shape of the torque and geaing (Spacing specifically).
You’re the guy who calls tech support before power cycling the device.
The GT3 revs to 9k becuase it has to to make the power.
The manual does nearly 100 in 2nd, how much gearing flexibility do you need. You can’t look at just max engine speed to assess gearing flexibility. You have to look at the shape of the torque and geaing (Spacing specifically).
You’re the guy who calls tech support before power cycling the device.
05-05-2018, 08:08 PM
#18
Melting Slicks
Thread Starter
If you can make 755hp at 6500 revs, there is no need to rev higher.
The GT3 revs to 9k becuase it has to to make the power.
The manual does nearly 100 in 2nd, how much gearing flexibility do you need. You can’t look at just max engine speed to assess gearing flexibility. You have to look at the shape of the torque and geaing (Spacing specifically).
You’re the guy who calls tech support before power cycling the device.
The GT3 revs to 9k becuase it has to to make the power.
The manual does nearly 100 in 2nd, how much gearing flexibility do you need. You can’t look at just max engine speed to assess gearing flexibility. You have to look at the shape of the torque and geaing (Spacing specifically).
You’re the guy who calls tech support before power cycling the device.
This car just got crushed at Nurburgring by a 520 Hp glorified VW bug with a 6 cylinder.
I'm the Corvette buyer who's trying to encourage people not to settle for GM's parts bin mentality.
I love my GS Z07.
But GM could do us so much better.
Last edited by fatsport; 05-05-2018 at 08:09 PM.
05-05-2018, 10:46 PM
#19
Melting Slicks
Also which Dodge? The Demon makes more power, but from the roll races I've seen, the ZR1 is faster. Also I'm pretty sure the ZR1 gets up to speed way faster.
05-06-2018, 10:50 AM
#20
Le Mans Master
No! ;)
Some people seem to bring the C6 into every C7 conversation. 500 more RPM isn't really something to brag about. There comes a time where you have to stop living in the past.
Plus, you went on to say that the C6 ZR1 also had titanium rods and titanium intake valves(as did the LS7) and it still had a 6,500 RPM rev limiter. You contradicted your entire point of bringing the C6 into the conversation.
Plus, you went on to say that the C6 ZR1 also had titanium rods and titanium intake valves(as did the LS7) and it still had a 6,500 RPM rev limiter. You contradicted your entire point of bringing the C6 into the conversation.
