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Discussion Starter · #1 ·
Has anyone ever built a flat plane CTS-V? in my planing stage, im looking at all available options.. I know there are LS flat plane builds but has it been done in a CTS-V?
Other than rpm, what are the benefits?
 

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Has anyone ever built a flat plane CTS-V? in my planing stage, im looking at all available options.. I know there are LS flat plane builds but has it been done in a CTS-V?
Other than rpm, what are the benefits?
I am wondering why you are considering doing this?

What are the advantages you are seeking?
Have you weighed the advantages against the disadvantages?

Cheers
 

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Duck, aren't there flat plane engines in the crash prone Mustangs that are SC, and make lots of HP very quickly because of fast revving those flat planes allow?
 
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Discussion Starter · #5 ·
I am wondering why you are considering doing this?

What are the advantages you are seeking?
Have you weighed the advantages against the disadvantages?

Cheers
I have weighed them and it's a no go on the flat plane.. especially ( imo) with a blower. Seems like a decent option for high reving na engine but still there are cons to them.. balance being the biggest I see..
It was one of those 💡 I had and made a post before researching... might have been a couple Blanton's in there too..lol
 

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buy a C8 Z06.
 

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I have weighed them and it's a no go on the flat plane.. especially ( imo) with a blower. Seems like a decent option for high reving na engine but still there are cons to them.. balance being the biggest I see..
It was one of those 💡 I had and made a post before researching... might have been a couple Blanton's in there too..lol
Some NHRA Pro Stock Teams over the years put much money into attempting to make more power with a Flat Plane Crank, rather than the Cross Plane Crank.

No more power was found!
Breakage was far more than with the Cross Plane Crank.
NVH, or "Noise Vibration and Harshness" drove the drivers dizzy.
 

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Duck, aren't there flat plane engines in the crash prone Mustangs that are SC, and make lots of HP very quickly because of fast revving those flat planes allow?
I am not really familiar with the SC version of the flat plane crank regarding Ford.

Third party information given to me, suggests the development of the flat plane crankshaft cost Ford many engines, which were destroyed during development, as well as a lot of money spent.

Drivers that were involved with those cars felt that the project was fruitless in the end, as the end result was a wash regarding actual reciprocating weight. This is stroke related and includes total reciprocating weight. . . Including the flywheel.

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In a race bred engine using a short stroke, the flywheel mass can be reduced using a flat plane crankshaft. Now the reciprocating weight can be less than a typical cross plane crank.

Also, since one is no longer firing two adjacent cylinders, a common
plenum manifold can be used, which should make for a big
difference regarding HP.

Cheers
 

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Some NHRA Pro Stock Teams over the years put much money into attempting to make more power with a Flat Plane Crank, rather than the Cross Plane Crank.

No more power was found!
Breakage was far more than with the Cross Plane Crank.
NVH, or "Noise Vibration and Harshness" drove the drivers dizzy.
I can't even fathom the vibration from a 500 cubic inch flat plane crank engine
 

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The only Ford flat plane crank engine is the GT350 which is NA, not SC. And it's not a great engine really. Most Ford guys I know would take a Performance Pack 2 GT or Mach 1 over a GT350. GM seems to have a much better job with the C8 Z06 than Ford did on the GT350. Racing is a prime example of that, Ford doesn't even use the flat plane for Michelin Pilot Challenge races that are only a few hours long because of durability issues. GM is racing 24 hours at a time with their FPC.
 

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The only Ford flat plane crank engine is the GT350 which is NA, not SC. And it's not a great engine really. Most Ford guys I know would take a Performance Pack 2 GT or Mach 1 over a GT350. GM seems to have a much better job with the C8 Z06 than Ford did on the GT350. Racing is a prime example of that, Ford doesn't even use the flat plane for Michelin Pilot Challenge races that are only a few hours long because of durability issues. GM is racing 24 hours at a time with their FPC.
Thanks for the info.

So the Fords get 1200 HP are all "traditional" cranks?
 
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Thanks for the info.

So the Fords get 1200 HP are all "traditional" cranks?
Yeah the Voodoo is the FPC version of the coyote engine. And the Predator is the supercharged beefy version of the coyote that is in the GT500 and is not FPC.
 

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I can't even fathom the vibration from a 500 cubic inch flat plane crank engine
One driver was quoted as saying because of the vibrations the
tachometer looked like it was the size of a salad bowl… Lol

In another case where this was tried the vibrations were so
horrific that the oil pan actually cracked.

Installing a flat plane crankshaft into your engine means your
existing headers now become 180° headers.

And while some like the sound, I personally don’t!
I also don’t like EV’s..... Don’t have any use for them.

I think the whole EV ideology is fraught with incompetence and pseudoscience..👎

Happy Holidays!
 

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lt's always fun to be the first on your block with a flat plane. I suspect Chevy will be selling them soon online. With blowers.
I doubt that. Flat plane only makes sense for an NA or Turbo engine where you can use the extra efficiency from the symmetric exhaust pulses.
You use a flat plane crank for high revving smaller engines which is kind of the opposite of a PD blower.

Plus because they can make the flat plane crank lighter I think a lot of times they are not quite as strong. You can still get big power but it seems like the low end torque of a PD blower is also at odds here.

I could see them keeping this fpc motor for the new C8 ZR1 and giving it turbos and or hybrid system but not a blower.
 
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Subaru's post is 'Right On'..:)

For those that still might be a little confused, here is a picture that might help. ..
Material property Font Graphics Brand Electric blue



And here we should take notice that no two cylinders fire together on the same bank.
Smile Font Circle Symbol Signage
 

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Plus in a V engine the cylinders are ~90 deg apart, so the 180 deg crank doesn't really jive...

A few years ago the Gibbs Toyotas in Nascar Cup suddenly had a really wild sound, like they were turning 1.5 times faster than all the other cars. I suspect they were doing a crossover set of headers, perhaps with a flat plane crank.
 

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Plus in a V engine the cylinders are ~90 deg apart, so the 180 deg crank doesn't really jive...

A few years ago the Gibbs Toyotas in Nascar Cup suddenly had a really wild sound, like they were turning 1.5 times faster than all the other cars. I suspect they were doing a crossover set of headers, perhaps with a flat plane crank.
the 90 degree V block doesn't mean you can't use a 180 degree flat plane crank. They are apples and bananas.
 

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You're right, and certainly I didn't mean that it can't work. I was moderately drunk when I posted that. I meant that a V engine doesn't naturally lend itself to a flat plane crank like an inline engine does.
 

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Just for additional clarification; one you put a flat plane crankshaft into your engine, your 'Existing Headers' become 180° headers. . . . .
 
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