Production of a Flat Plane Crank Engine
#1
Senior Badass!
Thread Starter
Production of a Flat Plane Crank Engine
With the reslease of Ford's new GT350 and its flat plane crank producing 526 FWHP out of a 5.2L V8, the stakes have changed and ante has been raised. High end Italian exotics have been making massive power from low liter engines for years and prior to 1920 the cross plane crank was not a thought. The cross plane come about to resolve vibration issues brought about by the flat plane crank. But surely with today's technology we can and have resolved this vibration issue. Secondly, light weight crank craves revolutions where the cross plane of yesterday is very heavy and robs power. Lastly, the exhaust note achieved is next to Godly and is desired by most any car enthusiast.
With that said, is the Corvette team considering producing a high horsepower, high revving, flat plane engine to compete in what seems to be the market trend of today? If so, is it in the concept stage or closer to production stage? Can dates be provided of when we may be seeing information being released?
With that said, is the Corvette team considering producing a high horsepower, high revving, flat plane engine to compete in what seems to be the market trend of today? If so, is it in the concept stage or closer to production stage? Can dates be provided of when we may be seeing information being released?
#2
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With that said, is the Corvette team considering producing a high horsepower, high revving, flat plane engine to compete in what seems to be the market trend of today? If so, is it in the concept stage or closer to production stage? Can dates be provided of when we may be seeing information being released?
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#5
Safety Car
Neat question. The Ford engine has equal output compared to the base Audi V10 which is also a 5.2L. The cost is likely only half of what it costs Audi to make one. In a pushrod design it's probably even cheaper than the DOHC V8.
It would also keep up the compactness of the pushrod orientation while increasing output. This is typically the small block ideology, a good packaging job.
It would also keep up the compactness of the pushrod orientation while increasing output. This is typically the small block ideology, a good packaging job.
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JDaniel (05-11-2021)
#6
Drifting
A quad cam engine (used to best achieve high revs) creates packaging problems for a front engine vehicle and a flat plane crank has vibration issues for any application. The packaging issues are less significant in a mid engined vehicle but the vibration issues never go away no matter where you put the motor. With the trend to forced induction I suspect that the advantages of a flat plane crank are only one of many considerations that will have to be weighed in determining the future of the Corvette powertrain.
#7
Senior Badass!
Thread Starter
I agree that all options need to be weighed. The pushrod is an excellent design and shouldn't be totally eliminated but I believe other avenues need to be explored.
Last edited by JDaniel; 06-07-2015 at 05:13 AM.
#8
Safety Car
I seriously doubt it. They've trudged onward in an effort to extract as much as possible from a pushrod V8. There is one more thing they can pull N/A, and that is to implement cam in cam like the Viper.
#9
Drifting
Since we are spitballing here, my near term Corvette wish-list motor is 6.5 liter, pushrod, porcupine head, normally aspirated V8 producing 500 horsepower. Think of it, a 21st century 396 small block rat motor powering the 2017(?) C7 Grand Sport. Talk about heritage!
#10
Safety Car
I'm curious if they can actually do more than cam in cam by using the existing vvt as well. Think that both intake and exhaust are phased by the vvt in the C7. Then, with cam in cam the exhaust is varied separately. Together both intake and exhaust! That's sufficient to catch up with McLaren, Lambo, and Nissan's GTR but maintain the pushrod small block footprint.
#11
Senior Badass!
Thread Starter
I still believe a flat plane crank is a valid option. Especially since the mid motor Zora is being discussed. I cannot believe we would throw an old cross plane push rod into a car starting at $150,000 and call it a day.
#12
Le Mans Master
Good question but you'll be told discussion of future products or possible implementation is a no go on here. That being said, I've appreciated the efforts made to extract as much as possible out of the traditional pushrod design. If the C8 becomes a rear mid engine design, I think Corvette needs to step up the "showpiece" nature of the engine packaging. The LT5 was the last Corvette engine you could pop the hood and just stare at it. I love that the exotics still maintain aluminum intakes. The only gripe I've had about the C7 are the goofy plastic coverings over the composite intake. The overall packaging of the engine bay is great....it's just those goofy plastics plastered on top of the engine. I would mind a few extra pounds if it meant a beautiful aluminum sculpted intake fit for a rear mid designed Vette came back. But I fear we're getting more black composite intakes with more in common with pickup trucks than premium in the future because composite is where it's at to "get it done".
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I would mind a few extra pounds if it meant a beautiful aluminum sculpted intake fit for a rear mid designed Vette came back. But I fear we're getting more black composite intakes with more in common with pickup trucks than premium in the future because composite is where it's at to "get it done".
#14
Le Mans Master
Mass for beauty's sake is, IMHO, a complete non-starter. The SBC is an ugly engine, but that's perfectly OK. Keep it hidden under the hood and let it do its thing, which is to obliterate the competition from a performance perspective. That's what matters when it comes to an engine. Not how pretty it looks.
I do think the rear mid is right around the corner with the next gen, if Corvette wants to keep upping the ante. If that happens, I know there will be a transparent window over the engine. Chevy was so adamant about showing off the top of a supercharger in the ZR1, so no way will they pass up displaying another Corvette first....I just hate the thought of such a big step for the marque and then we get ZR1/LT1 style engine covers filling the window.
#15
Drifting
It's my underatanding that apart from cosmetics the coil and intake covers serve the additional purpose of noise reduction.
As to the overall appearance of the SBC, it's my opinion that the engine proper is handsome in a classic sort of way. Where it falls short is in the cluttered appearance of the ignition coils and the associated coil and injector wiring harnesses. There are numerous photos on this forum of engines that have been "cleaned up" to, in my opinion, very positive effect.
I do think that a tip of the hat is due to Team Corvette for making the engine compartment quite clean all things considered. The twin cam V6 in my old 370Z should have been a gem but it was masked by a sea of hoses, harnesses and assorted clutter all of which are largely tucked away in the Corvette.
As to the overall appearance of the SBC, it's my opinion that the engine proper is handsome in a classic sort of way. Where it falls short is in the cluttered appearance of the ignition coils and the associated coil and injector wiring harnesses. There are numerous photos on this forum of engines that have been "cleaned up" to, in my opinion, very positive effect.
I do think that a tip of the hat is due to Team Corvette for making the engine compartment quite clean all things considered. The twin cam V6 in my old 370Z should have been a gem but it was masked by a sea of hoses, harnesses and assorted clutter all of which are largely tucked away in the Corvette.
#16
Pro
With the reslease of Ford's new GT350 and its flat plane crank producing 526 FWHP out of a 5.2L V8, the stakes have changed and ante has been raised. High end Italian exotics have been making massive power from low liter engines for years and prior to 1920 the cross plane crank was not a thought. The cross plane come about to resolve vibration issues brought about by the flat plane crank. But surely with today's technology we can and have resolved this vibration issue. Secondly, light weight crank craves revolutions where the cross plane of yesterday is very heavy and robs power. Lastly, the exhaust note achieved is next to Godly and is desired by most any car enthusiast.
With that said, is the Corvette team considering producing a high horsepower, high revving, flat plane engine to compete in what seems to be the market trend of today? If so, is it in the concept stage or closer to production stage? Can dates be provided of when we may be seeing information being released?
With that said, is the Corvette team considering producing a high horsepower, high revving, flat plane engine to compete in what seems to be the market trend of today? If so, is it in the concept stage or closer to production stage? Can dates be provided of when we may be seeing information being released?
So, you just have to decide what's most important to you..."prestige", or affordable performance that actually works. The Corvette group has always come down firmly on the latter and, personally, I'm glad they do. I hope they continue to do so. And as far as "today's technology" solving the vibration issue, it did so a long time ago...with the even-firing cross-plane crank. Newton's physical laws aren't going to change any time soon, so at the reduced engine speeds made possible by sufficient displacement, the cross-plane crank is, already, the most elegant solution.
Last edited by 1analguy; 07-01-2015 at 11:37 AM.
#17
Le Mans Master
And as far as "today's technology" solving the vibration issue, it did so a long time ago...with the even-firing cross-plane crank. Newton's physical laws aren't going to change any time soon, so at the reduced engine speeds made possible by sufficient displacement, the cross-plane crank is, already, the most elegant solution.
Michael
#18
Racer
Well put!
You're begging Tadge to travel down a dead-end road. GM has already investigated all of the whiz-bang, boy racer stuff and found it wanting. European and Asian manufacturers are artificially displacement-limited by their tax codes, so the only way they can deliver good horsepower is to rev the hell out of their engines. Remember, hp is a calculated value that's based on torque and rpm, and since relatively small displacement NA engines are limited in their torque output, a lot of rpms are required to achieve decent hp. Ferrari (and others) loves flat-plane cranks because they're lighter and stiffer, which makes their required elevated engine speeds easier to deal with. Now Ford is doing the same thing in the GT350. At what revs are those 526hp achieved? I'll bet they're quite elevated. I'd also like to know exactly how heavy the engine is. The previously-mentioned 8250rpm, 600hp Lamborghini V10 delivers 1.05hp per pound of engine weight, while the 8250rpm, 500hp NA flat six in Porsche's 911 GT3 RS only delivers 0.85 hp/lb. The current LT1 comes in at 1.02 hp/lb. The mildly-tuned LS7 delivered 1.15 hp/lb. That's 0.1 hp/lb better than the sweet-sounding Lambo V10, and the LS7 is 130lbs lighter in the bargain! I'll be polite to Lamborghini and, especially, Porsche by not getting into the torque/driveability issue. Someone mentioned the Lotus-designed, high-reving LT5. In it's never-released-for-production 475hp form, it delivered only 0.73 hp/lb. All that extra mass can really work to negate the meaningless hp/L numbers.
So, you just have to decide what's most important to you..."prestige", or affordable performance that actually works. The Corvette group has always come down firmly on the latter and, personally, I'm glad they do. I hope they continue to do so. And as far as "today's technology" solving the vibration issue, it did so a long time ago...with the even-firing cross-plane crank. Newton's physical laws aren't going to change any time soon, so at the reduced engine speeds made possible by sufficient displacement, the cross-plane crank is, already, the most elegant solution.
So, you just have to decide what's most important to you..."prestige", or affordable performance that actually works. The Corvette group has always come down firmly on the latter and, personally, I'm glad they do. I hope they continue to do so. And as far as "today's technology" solving the vibration issue, it did so a long time ago...with the even-firing cross-plane crank. Newton's physical laws aren't going to change any time soon, so at the reduced engine speeds made possible by sufficient displacement, the cross-plane crank is, already, the most elegant solution.
#20
Drifting
If it happened it would be fun but unless it's done in concert with changes like forced induction or some sort of hybrid power train I think it's a bit of an engineering dead end. The reason it works for the Mustang is because the Ford engine is on the outer fringes of flat plane crank practicality whereas the larger Corvette engines would seem to be beyond near term practical limits. If Chevy were to follow the current trend towards smaller boosted engines with hybrid assist that could open the door to a smaller engine with a flat plane crank. Due to fuel efficiency mandates this issue is probably very much in play at this moment. For today however I don't think a flat plane crank for the current displacement of LT series engines is in the cards. However, if Team Corvette comes up with some Magical-Hydro-Electronic-Self-Dampening motor mounts that allow unlimited displacement flat plane crank engines all I can say is sign me up for a test drive.
Last edited by Guard Dad; 06-21-2015 at 10:00 PM.