C8.R packs in flat-plane V8
09-22-2018, 10:27 PM
#81
Safety Car
Member Since: Jan 2012
Location: Cin City
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St. Jude Donor '14
With the leaked audio clip C8.R sound in which the engine sounds smooth and deep. It can most-probably be result of Flat-Plane crank. First I thought it was due to implementation of Turbos, but turbos cannot make Corvette Cross-plane V8 sound like that nor can exhaust system. Yes I realize that it is not official but the audio clip of the C8.R sound make it sound more like European V8 and only deduction for it can be inclusion of flat-plane crank instead of cross-plane.
Audio Clip of C8.R:
https://sportscar365.com/industry/au...-turbo-engine/
Finally Chevrolet decides to drop in Flat-plane V8 in Corvette. Never thought they will drop it in so soon. This video makes my point even strong.
Sound of C8:
https://www.youtube.com/watch?v=TyV8K7Vrp7k
This video makes my point of it being FPC V8 even strong.
Audio Clip of C8.R:
https://sportscar365.com/industry/au...-turbo-engine/
Finally Chevrolet decides to drop in Flat-plane V8 in Corvette. Never thought they will drop it in so soon. This video makes my point even strong.
Sound of C8:
https://www.youtube.com/watch?v=TyV8K7Vrp7k
This video makes my point of it being FPC V8 even strong.
09-23-2018, 12:30 AM
#82
I do do wish we had more insight to the failure modes of the voodoo, because I think people are partially nervous because of the unknowns. My engine now has 32,000 miles and 5 track days, so I think I got a good one. I applaud Ford for having the courage to release such a crazy engine, but I also think the vette is better suited to a cross-plane DOHC engine.
-T
09-23-2018, 02:30 AM
#83
Interesting theory, but after racing a DOHC ATSV the past couple years, I believe you're just hearing the extra valves as the ATSV despite being a V6 is very throaty when we added our exhaust to it. Plus the flat plane cranks have terrible vibration issues and Ford will NOT be continuing the engine in the 5.2L found in the GT500. Their warranty issues resulting in this have been a mess for failed engines, despite the amazing sound of the engine.
https://www.youtube.com/watch?v=XU4Ss0rSyPc&t=3s
https://www.youtube.com/watch?v=cktSxPXCQa8
https://www.youtube.com/watch?v=XU4Ss0rSyPc&t=3s
https://www.youtube.com/watch?v=cktSxPXCQa8
Second point if they really go with FPC then I expect Chevy to solve the vibration problem with either going for low displacement engine in combo of turbo(this is what I believe they are doing) or add in dampening to reduce it as much as possible.
Last edited by King Dranzer; 09-23-2018 at 02:33 AM.
09-23-2018, 02:30 AM
#84
OTOH, it isn't like Ford has had a lot of experience with its design.
I think it's a bit unfair to consider their efforts a Fail.
and, frankly, unless they are wound up, they don't even sound good.
You might be onto something...
Ferrari has always had a tradition of small displacement engines in their cars.
if so i believe the twin turbo, flat plane crank engine size will have to follow ferraris lead....
i could be wrong but ferrari went to 3.9 liters in its flat plane crank turbo v8 for a reason...
i dont knkw the reason but there must have been a reason..
i could be wrong but ferrari went to 3.9 liters in its flat plane crank turbo v8 for a reason...
i dont knkw the reason but there must have been a reason..
There are a couple of reasons for this.
A) Small = lighter weight, as well as a compact form-factor.
B) Racing series they compete in almost always mandate small displacement. Ferrari is a manufacturer unlike any other: race 1st, sell 2nd.
I did not like the high RPM feel of the LT1, nor the throttle response.
I also think the vette is better suited to a cross-plane DOHC engine.
Anything that looks and handles as well as a late-model Corvette DEMANDS a cross-plane DOHC.
Putting a truck motor in it is just plain silly.
09-23-2018, 03:17 AM
#85
I believe that I read somewhere that GM will be using active engine mounts to quell vibration.
09-23-2018, 01:21 PM
#86
Safety Car
Pray tell, what's a DOHC engine got to do with good handling? Yoo telling me that a heavier engine with a high Cg and a very long timing chain or belt and at least $600 in increased costs is better for handling? Tell me the advantages,especially with a blown version with 4 VPC?
Last edited by Shaka; 09-23-2018 at 01:22 PM.
09-23-2018, 03:22 PM
#88
Le Mans Master
I have ZERO interest in a flat plane crank engine in the Corvette. Too much vibration, and, frankly, unless they are wound up, they don't even sound good.
What I don't kindle is blaming the architecture of FPCs for the failure of one embodiment.
The following 2 users liked this post by King Dranzer:
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10-19-2018, 02:20 PM
#92
Interesting theory, but after racing a DOHC ATSV the past couple years, I believe you're just hearing the extra valves as the ATSV despite being a V6 is very throaty when we added our exhaust to it. Plus the flat plane cranks have terrible vibration issues and Ford will NOT be continuing the engine in the 5.2L found in the GT500. Their warranty issues resulting in this have been a mess for failed engines, despite the amazing sound of the engine.
https://www.youtube.com/watch?v=XU4Ss0rSyPc&t=3s
https://www.youtube.com/watch?v=cktSxPXCQa8
https://www.youtube.com/watch?v=XU4Ss0rSyPc&t=3s
https://www.youtube.com/watch?v=cktSxPXCQa8
10-19-2018, 05:34 PM
#93
Burning Brakes
Amen, Brother ! If you are an engine designer, HP/Ltr is the metric, but if you are a sports or race car designer, HP/# is the thing that counts. Lot of would be engine designers on this forum but few would be auto designers. In every venue where displacement is not penalized, (Can-Am, Offshore Boat Racing, Aircraft Engnes), Displacement is the much preferred approach to getting more power, because it is lighter and more reliable.
One more fun fact - high output from small displacement is a reaction to either taxes based on displacement or competition formulae which cap displacement.
One more fun fact - high output from small displacement is a reaction to either taxes based on displacement or competition formulae which cap displacement.
The following 4 users liked this post by dcbingaman:
10-19-2018, 07:50 PM
#94
Le Mans Master
HP per liter is only a thing where gas mileage requirements dictate it. In every other case a larger displacement motor is desirable. Especially on the street.
10-19-2018, 11:56 PM
#95
Le Mans Master
Not all of the Italians. Maserati takes the same engine that goes into Ferraris, and puts a cross-plane crank in.
10-27-2018, 07:53 AM
#96
Le Mans Master
Somebody say destroked!? ;)
Did somebody say Tadge spoke to this!?
Simply changing the engine dynamics negates much of the need for computer intervention. ME layout same - same.
Not sure how this will sort out, only that the core of which that this is a fresh start with easy money changes therein.
(The OHV has a low CoG that the Corvette Racing competition has hated!)
Not sure how this will sort out, only that the core of which that this is a fresh start with easy money changes therein.
(The OHV has a low CoG that the Corvette Racing competition has hated!)
Last edited by johnglenntwo; 10-27-2018 at 07:21 PM.
12-09-2018, 09:57 AM
#98
Melting Slicks
Member Since: Jul 2014
Location: Bonita Springs Florida
Posts: 2,195
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I don't know what it is, but to my ear it sounds great. Reminds me of the F1 cars. If the car can produce max torque low in the RPM range, the car should be a beast. Personally I prefer to see the big torque number around 1400RPM rather than 3000-3500. Call it instant gratification or whatever, but it puts a huge grin on my face.
Last edited by 1SG_Ret; 12-09-2018 at 10:48 AM.
12-09-2018, 10:41 AM
#99
Moderator
That's funny, after listening to the video above your post I was like man that sounds similar to an F1 engine at lower revs....indeed it does. My vote is for a TT small disp V8. No idea about the FPC issue.
Last edited by Zjoe6; 12-09-2018 at 10:42 AM.
12-09-2018, 11:25 AM
#100
Ben and Dcbingamen pretty much nailed it. I've DD'd and tracked a DOHC and a couple of pushrod cars (including a C6Z), and now have 20,000 miles on my GT350R. The C8R in the clip does not sound like a FPC, and I tend to agree it's probably a TT V6.
Some posters have called the Voodoo a "failure" or a "fad," while Trackaholic says the engine is terrific for a track car (and seems to imply it should therefore be a good race car engine). And Sunsalem defends the FPC generally and also suggests the C8R may have a FPC too. Those comments aren't entirely wrong.
There are plenty of FPC cars out there, but none (that I'm aware of) as large / heavy as the Voodoo, at least that are in mass production. Ford's accomplishment with the Voodoo was not only sufficiently mitigating the NVH for such a large engine, but, more broadly, in authorizing and executing the entire program when it was probably seen as a risky project.
The main reason, as I see it, why the Voodoo is seen by many as a failure or fad is the long term effects it's harmonics have on the integrity of the entire car. Ford seems to have adequately addressed noise (in fact it's glorious) and vibration (e.g., the mass dampers on the exhaust). But there's no way to adequately mitigate the transitory excitations of the natural frequencies of hundreds (thousands?) of components and subassemblies throughout the car - and, yes, I mean relative to those imparted by a CPC engine of equal displacement. That will absolutely cause premature wear of everything - instrument bezels, seals, fasterners, etc etc. If the Voodoo weighed only 100 pounds, the amplitudes of those vibrations would be sufficiently damped out. But in the case of an FPC, size (scale) does matter. I can hear, see and feel those effects already in my R. I seriously doubt the Corvette customer, especially the new ones (who are the brand's lifeblood), would enjoy that experience the way older, "hard core" car guys like me (and Trackaholic) do. And Chevy knows it. I think Chevy would conclude (has already) that the novelty and other arguable advantages of a FPC don't warrant the engineering necessary to design and integrate an FPC into their new mid-engine platform, especially since it would still have markedly more pronounced NVH than a CPC engine.
As to the Voodoo's trackability: there's no doubt that's where the car really shines. But there is an enormous gulf between repeated HPDE sessions and weekends versus competitive racing. I would expect a large displacement FPC to be less dependable and durable than a CPC engine of the same displacement. And Ford seems to have already decided the matter for their racing program.
Some posters have called the Voodoo a "failure" or a "fad," while Trackaholic says the engine is terrific for a track car (and seems to imply it should therefore be a good race car engine). And Sunsalem defends the FPC generally and also suggests the C8R may have a FPC too. Those comments aren't entirely wrong.
There are plenty of FPC cars out there, but none (that I'm aware of) as large / heavy as the Voodoo, at least that are in mass production. Ford's accomplishment with the Voodoo was not only sufficiently mitigating the NVH for such a large engine, but, more broadly, in authorizing and executing the entire program when it was probably seen as a risky project.
The main reason, as I see it, why the Voodoo is seen by many as a failure or fad is the long term effects it's harmonics have on the integrity of the entire car. Ford seems to have adequately addressed noise (in fact it's glorious) and vibration (e.g., the mass dampers on the exhaust). But there's no way to adequately mitigate the transitory excitations of the natural frequencies of hundreds (thousands?) of components and subassemblies throughout the car - and, yes, I mean relative to those imparted by a CPC engine of equal displacement. That will absolutely cause premature wear of everything - instrument bezels, seals, fasterners, etc etc. If the Voodoo weighed only 100 pounds, the amplitudes of those vibrations would be sufficiently damped out. But in the case of an FPC, size (scale) does matter. I can hear, see and feel those effects already in my R. I seriously doubt the Corvette customer, especially the new ones (who are the brand's lifeblood), would enjoy that experience the way older, "hard core" car guys like me (and Trackaholic) do. And Chevy knows it. I think Chevy would conclude (has already) that the novelty and other arguable advantages of a FPC don't warrant the engineering necessary to design and integrate an FPC into their new mid-engine platform, especially since it would still have markedly more pronounced NVH than a CPC engine.
As to the Voodoo's trackability: there's no doubt that's where the car really shines. But there is an enormous gulf between repeated HPDE sessions and weekends versus competitive racing. I would expect a large displacement FPC to be less dependable and durable than a CPC engine of the same displacement. And Ford seems to have already decided the matter for their racing program.
Last edited by GrampZ; 12-09-2018 at 12:20 PM.