Why Did Ford Decide to do a Flat-Plane Crank Differently?

[wooz]

At last, some light shed on the exact issue I have been trying to explain/get to the bottom of:

http://www.edmunds.com/ford/mustang/201 ... plane.html

So...if I am reading into it right...its all about MARKETING! The sound it makes seems to have driven the decision making on the odd layout.

Annoyed I didn't find that in my searchings.

Great post j0nr. You really understand v8 crankshafts. You're right, it is confusing why Ford would introduce extra vibration by changing the flat crank to a form no one else uses. But, just when you think you see the light, it's a mirage. The sound of this engine is different than other flat crank 8s I'm sure, but that is not because of the crank chosen. The different crank has nothing to do with the different sound. Ford marketing probably did want to make their engine sound different than a Euro flat crank v8, but they did this with their weird exhaust. As you know a flat crank v8 fires alternate banks, and that makes it sound different than a cross plane crank that must fire the same bank twice in a row (two same side firings in one firing sequence since each bank goes through a same side firing event). However it doesn't change the sound by firing for example the second hole on the left bank instead of the third hole- the sequence is still side to side. You could change the crank throws on a cross plane crank for example if you switched throw 2 and 3 side to side, and the firing order would change, but you would still end up firing both banks consecutively somewhere in the firing order, and the sound would be the same. Chevy did change their firing order with their LS1 motor over the small block (they didn't change the crank), but the sound didn't change because of it. I read the link you put in this post, it was interesting. I think the answer to why Ford did such a wild crank design can be found in the link Brian Coat put up. In that link they talk about Ford's single phlenum (sic) design and how it was simpler to implement, but it appears the way they set up their intake runners etc it was easier to get it to work if they messed with the crank and changed the piston positions to match the intake instead of the other way around. If it were me I think I would have tried to keep the normal flat crank and make the intake system fit it. At least that is why I THINK Ford did this wild crank design. I am not 100% sure that is the reason for the crank, but I am 100% sure the crank did not change the sound compared to another flat cranker. That was done in the exhaust system. In those links it said Ford tried all three flat crank possibilities. I assume the 3rd possibility is a UUDD crank. Now that would really be weird, but it would also not change the basic flat crank v8 sound. You can hear the difference between a flat crank and a cross plane because the sound waves are not even coming out of bank of a cross plane.. they go xx _x x. But in a flat crank they come out of a bank evenly x x x x. You can't tell if they come out 1 3 4 2 or 1 4 2 3 it's an even flow either way. I really liked your post. Nice pictures, and interesting information.

[Fifty]

Since all of the tech stuff seems to have been covered and my "search fu" is weak...

Does ford make this motor? The motor comes from Germany according to the paper on the window, the tremec from Mexico etc...

So if ford doesn't make it, who does? Or does ford have a warehouse full of.... Ok I had to stop and keep it PC.... In Germany assembling motors?

[JordanMugen]

I am 100% sure the crank did not change the sound compared to another flat cranker. That was done in the exhaust system.

Here's a comparison of a stock GT350 exhaust manifold to a GT350 fitted with an aftermarket-made conventional 4-1 exhaust manifold: https://www.youtube.com/watch?v=8DCVTLI1EXU
The aftermarket 4-1 certainly sounds more Ferrari-ish albeit still a little throaty, I guess it would be more raspy if it was a 4-2-1 manifold. To me it still seems like, even with the conventional manifold, there is still something inside the engine that is making it sound different to standard flatplane V8 [it may just have an X-pipe I guess, as I notice that Ferraris with X-pipes have a somewhat throaty sound too].


I am curious to see what the stock GT350 exhaust manifold looks like?

Is it a a kind of unequal length manifold, like on an old Subaru?

It occurs to me you could use a kind of GT350-like exhaust manifold to give a unique sound to a conventional Judd or Mechachrome racing V8 (e.g., F3000/LMP2/GP2) engine. Which would be a nice talking point.

For instance, take the Formula Thunder 5000 cars in Australia -- instead of using a heavy production 195kg crossplane Coyote V8 to give the "thunder" to appease certain fans; they could just an off-the-shelf lightweight racing flatplane V8 (like the Judd at 116 kg) and then just use the exhaust manifold to give the burbling sound that some fans like?

Edit ---

Aha! Here is a picture of the stock Shelby GT350 manifold which shows that it is indeed a unequal length exhaust manifold; quite similar to the factory exhaust manifold on an old Subaru turbo. The first Y is slightly unequal, but the second collector where not just the two first cylinders but both cylinders three and four all join up is very unequal. In fact, the GT350 just uses a manifold similar to what is used on the regular Mustang GT -- seemingly packaging (at least with allowance for OEM catalytic converters) does not allow for an equal length manifold.

Mystery solved.

[strad]

looks like different bolt patterns

[Maritimer]

Since all of the tech stuff seems to have been covered and my "search fu" is weak...

Does ford make this motor? The motor comes from Germany according to the paper on the window, the tremec from Mexico etc...

So if ford doesn't make it, who does? Or does ford have a warehouse full of.... Ok I had to stop and keep it PC.... In Germany assembling motors?

Ford make it. That's their plant on Cologne, the Focus is made there as well.

[Edax]

Since all of the tech stuff seems to have been covered and my "search fu" is weak...

Does ford make this motor? The motor comes from Germany according to the paper on the window, the tremec from Mexico etc...

So if ford doesn't make it, who does? Or does ford have a warehouse full of.... Ok I had to stop and keep it PC.... In Germany assembling motors?

Ford make it. That's their plant on Cologne, the Focus is made there as well.

I think they have been making high performance engine’s there for a long time. Not the first Mustang engine which was made there. Ford also has an research facility in Aachen germany.

I also don’t think it has anything to do with cost cutting as wages are not exactly lower in Europe. Main reason might be that since the oil crisis engine technology in Europe has advanced much more than in the US where oil prices have been traditionally much lower. At prices north of $7/ gallon and restrictive environmental regulations there is quite a consumer drive for innovation.

Admittedly some of that technology went in fooling the regulators (VW) but much of it presents actual benefit in terms of performance and fuel economy. Now that the prices in the US are also rising that technology finds its way in the US cars. If you look around you’ll find a lot of the US cars and trucks have European engines, turbo’s, tranmissions etc.

[Maritimer]

Ford have developed most of their recent cars in Germany, the American facilities focus primarily on trucks and SUVs. It's nothing to do with tech and more with facility infrastructure I'd wager, it it were simply a matter of euro engineers being better they could just ship them to the states.