Voodoo Child

[DHG1078]

Nice info TOB! I am so jealous you guys get to talk to the Ford engineers! Being an engineer myself, I would love to just sit down with these guys and pick their brains. Especially on materials related topics as I am a Materials Engineer.

You have peaked my interest on the rods. You posted a lot of good info on the material. Especially this bit:

The 46MnVS6 material is a fine-grained ferritic-pearlitic micro alloy forged steel

I am not up to speed on this material, but I have a good background in steel. I look forward to reading into this when I have time.

 

[DSG2003SVT]

You guys that have heard this car in person, what do you think about how it sounds?

 

[Grant808]

GT350 exhaust tips. The place where internet myths are born.



Jamal asked if we could debunk a myth that he continues to see on the web with respect to the tail end of the exhaust system. Any number of internet experts have commented negatively about the "tube within a tube" as if it was some sort of cosmetic afterthought, and it isn't. Jamal mentioned how its design allows cool air to pass through the outer tube and around the tailpipe. Both Travis and I commented that we understood it to be similar to that of the diesel trucks at that juncture and Jamal agreed. He then mentioned that those who remove the outer tube and track or run their GT350 hard may find a heat distorted rear fascia as a result.

Ok, but how is that different from this on the IS-F? I'm still not a fan of the fake tips.

Anybody removing the fake tips on the GT350 for the track just wouldn't be that smart!

 

[DSG2003SVT]

It's different than the ISF tips because the ISF tips are freakin hideous.

 

[DHG1078]

Ok, but how is that different from this on the IS-F? I'm still not a fan of the fake tips.


Anybody removing the fake tips on the GT350 for the track just wouldn't be that smart!

I believe the "fake" tips on the GT350 are attached to the exhaust pipes aren't they?

 

[DHG1078]

Even if they aren't attatched, they should overlap some to act as a heat shield in essence. The ISF tips are purely for show.

 

[Grant808]

I believe the "fake" tips on the GT350 are attached to the exhaust pipes aren't they?

Not attached. I saw them on day 1 at the LA auto show.

I don't understand what the internet myth is. This is the one cosmetic bit that I DO NOT like about the car.

 

[DHG1078]

Not attached. I saw them on day 1 at the LA auto show.

I don't understand what the internet myth is. This is the one cosmetic bit that I DO NOT like about the car.

Interesting. All the pics I saw kinda looked like they were attached.

 

[krt22]

Although im sure they are largley cosmetic, some where in one of these articles/run downs they said they are to prevent melting/warping of the bumper.

 

[Grant808]

Interesting. All the pics I saw kinda looked like they were attached.

<- Because photographer and car guy. ;-) And GT350 buyer...and sometimes track rat. :-D So I kinda care.

 

[DHG1078]

Although im sure they are largley cosmetic, some where in one of these articles/run downs they said they are to prevent melting/warping of the bumper.

Ya and that was what Jamaal told TOB in the OP.

The solution makes sense. I wonder if their is another alternative though that would be close in price?

 

[krt22]

Not really, metal heat shields are used like this all the time. You could use other materials like ceramics and what not, but you sacrifice durability while likely adding weight/cost

 

[F8L SN8K]

For those that want to compare it to the Boss Heads. This is what my set originally looked like for my SCJ.

 

[Tob]

Being an engineer myself, I would love to just sit down with these guys and pick their brains. Especially on materials related topics as I am a Materials Engineer.

You have peaked my interest on the rods. You posted a lot of good info on the material. Especially this bit:

I am not up to speed on this material, but I have a good background in steel. I look forward to reading into this when I have time.

Very cool. It was indeed fascinating to talk shop with some of the best of the best. My hope is to glean as much data as possible in order to gain a better understanding. There is nothing better than hearing of an engineering principle or concept and how it was used to make a better vehicle, especially if the vehicle showcases some of the latest technologies in the performance car segment. These guys not only think on another level but are all extremely good at explaining things in relative terms.

You guys that have heard this car in person, what do you think about how it sounds?

It does sound just a little different than what we are all used to. You ever hear a car that has you turn to look not because of how loud it is but rather because it just sounds right? Well this is that exhaust, only different.:-D


If I had to describe it in one word....badass.

[video=youtube;qlWPW0SHwu0]https://www.youtube.com/watch?v=qlWPW0SHwu0[/video]

Not attached. I saw them on day 1 at the LA auto show.

I don't understand what the internet myth is. This is the one cosmetic bit that I DO NOT like about the car.

Life is short. If you have the ability to change something to make it what you want it to be then do it and don't ever look back. Even though the volume is going to be fairly low just about every aftermarket exhaust manufacturer is chomping at the bit to offer their version of the perfect exhaust system. And Ford knows this will happen as the Mustang aftermarket, especially the exhaust contingent, is huge.

That said, Ford engineers went through the entire system from the snazzy factory stainless headers shown on the previous page, to the tuned "X" section, to the dual mode mufflers, to the air-cooled tips. A well integrated system from beginning to end. But feel free to make it "better" - I'll probably do the same thing if I get one. Regardless, I respect the effort that went into the OEM system very much.

For those that want to compare it to the Boss Heads. This is what my set originally looked like for my SCJ.

Those are absolutely gorgeous. And to think that engineers a few decades ago played with Tunnel Port heads which required pushrod tubes, miniscule 289/302 heads, dead-lazy Cleveland and Lima heads, all of which were supposed to be marvels when introduced. We have come a long way what with factory CNC'd alloy heads that have been taken to the limit with endless hours of computer simulation and dyno testing. I'd have bet the farm a few years ago that we'd never see compression ratios this high ever again. Amazing stuff.

 

[Tob]

I spent a little time comparing components between the 5.0 Coyote and the 5.2 Voodoo powerplants. I started by placing one of F8L's Coyote Boss CNC exhaust port shots next to that of the 5.2L engine.

Rod and piston comparison.

Note how the bottom of the "beam" between the skirts on the Mahle 5.0 piston is scalloped while it runs straight across on the Mahle 5.2 piston. In addition, the 5.2 piston has a triangulated support which runs from the end of the piston pin boss up to better support the piston top and ring areas.

I'm fairly certain that you are seeing Mahle's insignia (upper right) and not Metaldyne's.

Regarding the oil pan and windage tray I see quite a bit in common. Follow the rubber gasket path all the way around as well as the bolt inserts.

And a shot I found of the 5.2 "X" section. My initial thoughts were that this looked like a casting which seemed odd but after seeing the cast collector at the end of each header now I'm starting to believe it could be cast 300 or 400 series stainless.

Regarding the exhaust headers we previously discussed, I found this SAE article that provided additional insight into how they came to be on the Coyote engine a few years ago, paving the way for headers on the 5.2 as well. Interesting that those were done by Benteler Automive and that the 5.2 headers are being done by Watson Engineering.

In addition to adding displacement and boosting the flow of air into the engine, Ford’s engineers also streamlined the flow of air out of the engine. Its innovative tubular exhaust headers are credited with increasing output by 6 hp and 15 lb·ft (4.5 kW and 20 N·m, respectively), according to Adam Christian, the program's intake, exhaust and combustion engineer.

Working within the package constraints of the Mustang's engine-compartment space, Ford’s engineers were stumped by the challenge of designing extremely compact headers that would both minimize the effect of the destructive power pulses and maximize the effect of the beneficial ones.

Mulling the problem while in the shower, Christian had an epiphany. Rather than trying to create a header design that optimized the potentially useful exhaust pulses, he decided instead to create one that eliminated the power-robbing impact of the destructive ones, by simply pairing adjacent cylinders.

He carried some lengths of steel tubing home and welded up a prototype in his garage workshop. Two weeks later its effectiveness was proven out on the dyno.

Christian said he was motivated to devise the unorthodox solution by his team leader Mike Harrison, who told him, “Adam, just make it happen.”

The production tubular headers are manufactured by Benteler Automotive Corp. Christian admits that while their price premium compared to cast iron manifolds has caused some contention within the company, the power benefit is worth it.

From here.

As Adam hinted during the reveal, that contention has turned into expectation. Huge props to a guy that takes his work home with him and convinces the corporate mindset to change. I couldn't imagine attending this reveal and photographing a cast iron log-style exhaust manifold, however optimized for performance it may have been.

 

[TORQUERULES]

I spent a little time comparing components between the 5.0 Coyote and the 5.2 Voodoo powerplants. I started by placing one of F8L's Coyote Boss CNC exhaust port shots next to that of the 5.2L engine.

Much more volume in the bowls on the 5.2 and notice the difference in valve spacing. I am surprised that it is this noticeable. A lot taken out of the divider too. Much different port shape overall...

It also looks like the CNC work on the 5.2 is much more precise and smooth.

Of course the angle of the 5.2 pic could be throwing my off and I am all wrong. Lol.

 

[Serpent]

Does anyone know if this car is using a two peice steel drive shaft? or One peice aluminum maybe even Carbon Fiber DS?

 

[SID297]

Does anyone know if this car is using a two peice steel drive shaft? or One peice aluminum maybe even Carbon Fiber DS?

2 piece steel.

 

[scv8]

This is an EPIC post. Thank you for sharing! :rockon::beer:

 

[F8L SN8K]

Much more volume in the bowls on the 5.2 and notice the difference in valve spacing. I am surprised that it is this noticeable. A lot taken out of the divider too. Much different port shape overall...

It also looks like the CNC work on the 5.2 is much more precise and smooth.

Of course the angle of the 5.2 pic could be throwing my off and I am all wrong. Lol.

The tooling marks are much more precise and smooth.(mind you don't want a glass smooth surface). That was the item I was really disappointed in was on my right head. The work piece had shifted during the run and has a noticeable step and tool chatter. So much so that another set was ordered. Of course in stock eliminator you buy several sets of everything to see what performs the best.

The ceiling of the 5.2 has a very distinct air diffuser on the roof of the ports(Intake and exhaust). The Combustion chambers look pretty much identical.

These have more lift then the CJs. .511(13mm) vs .551(14mm). The factory 11-14 coyote could only run up to a .472(12mm). The boss heads were designed to be able to run up to the 13mm without extra machine work. This is a lot of lift for a 4v curtain area. The factory stock SCJ cams have a lot of duration in them but are still able to use the full sweep of the TiVCT. Curious what this duration and sweep is.