GM Engineer about the 350 fpc.

[AvalancheSVT]

I wonder if given enough time the aftermarket will sort out the voodoo engines since ford apparently just didn't have enough time and resources available to get it done the first time.

i'm not joking, sounds like they had a budget while GM had a blank check... or maybe we're just gonna see the same issues with that one since htey only increased the displacement over the voodoo.

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[ice445]

it's basterdized. Ford marketing pukes ought to be hung for what they did.

They took what should have been a great platform and hobbled it.

It should be primary balanced. But instead, Ford decided to use a dumbass firing order which means you now have to add the heavy counterweights (thus negating one of if not THE biggest reason/advantage of the FPC).

So what you end up with is a motor that has the worst of both worlds, it has the counterweights of a cross plane crank, but the secondary imbalances of a flat plane crank (and all the NVH issues that go along with it).

The ONLY advantage (and it's marginal) is you get the even tuning of one bank per side firing so you end up with less "lazy" cylinders, but Ford even screwed that up a bit by the unique y arrangements of the stock headers. They're purposefully creating an exhaust traffic jam to improve the sound.

Now, admittedly, I LOVE the sound of the voodoo, the combination of muscle growl with the refinement of exotic wail,

But beyond the sound, the motor is almost as if they said "let's take the biggest drawback of each motor and combine them into one!"

Yeah, can't agree with you on this one. You're acting like Ford looked at the way it's always been done and decided that was dumb, and that they could do it better. The Voodoo was not only designed around specific fixed constraints, but the engineers did not want it to sound like a traditional FPC engine. They wanted to make something special and unique, and they did that. I can guarantee they expected severe challenges taking the direction they did, but for the most part the engines work pretty well. 526HP isn't too bad for a "dumbass" design.

Not everything in life needs to be the most "optimal" to be worthwhile. Afterall, you admit to loving how they sound and you seem to have bought one, so it can't be that bad ;)

 

[MNGT350]

No I believe he’s referring to a quote from one of the GM engineers talking about how they figured the heavy vibration of the Voodoo was either a design issue or because of the UDDU crank order, and that they wouldn’t have to contend with the same issue. Then on the engine dump they kept having a loose oil filter and couldn’t figure out why until they did a slow motion video and saw the engine shaking the filter loose even with the UDUD firing order.

Think this is it, from Jordan Led
https://www.corvetteblogger.com/202...using-havoc-on-early-lt6-development-engines/

This is interesting. Supports the idea that is talked about often regarding Ferrari V8 engines, that once you start getting over 4 liters the vibrations are a bigger problem, and your dampening needs increase, which can outweigh some of the flat plane benefits.

 

[Angrey]

Yeah, can't agree with you on this one. You're acting like Ford looked at the way it's always been done and decided that was dumb, and that they could do it better. The Voodoo was not only designed around specific fixed constraints, but the engineers did not want it to sound like a traditional FPC engine. They wanted to make something special and unique, and they did that. I can guarantee they expected severe challenges taking the direction they did, but for the most part the engines work pretty well. 526HP isn't too bad for a "dumbass" design.

Not everything in life needs to be the most "optimal" to be worthwhile. Afterall, you admit to loving how they sound and you seem to have bought one, so it can't be that bad ;)

It was a dumb decision. The entire point of going flat plane instead of cross plane is to eliminate the heavy counterweights on the crank shaft. You do that knowing it's going to cause secondary rocker vibrations, but you're willing to live with the secondary vibes because....racecar and the lighter crank shaft will help you rev faster and the even exhaust pulses will help everything from scavenging to cylinder temp uniformity.

What Ford did was get halfway into that path and say "well, we don't want it to sound like a ferrari so we're going to change the firing order" to which someone said "yeah, but now we have BOTH primary AND secondary imbalance" and then someone said "well, just put counterweights on the crankshaft."

Furthermore, the secondary benefit of even exhaust pulses was corrupted when to enhance the sound further, they gave an unequal weird 3 into 1 and 2 into one header design.

And we still have to deal with the secondary imbalances of a large motor, which requires extra weight and dampening (weights on the trans, weights on the exhaust) as well as all the latent issues (like oil filters backing off).

As Honey Badger has demonstrated, while the voodoo is great, it's just not suited for long harsh use, the vibrations end up problematic in a number of areas.

Do I love the sound of my voodoo? Absolutely. Is it worth all the detriment? That's only a question each individual person can answer.

I didn't realize that the crankshaft was essentially a CPC crankshaft flattened out until after I bought the car.

To be honest, if Ford didn't go to the god awful sounding flathead firing order in the coyote/variants, I'd say give me the CPC all day. But the drop from voodoo all the way to the trashy CPC offerings is substantial. The 4V modulars sounded magical. The coyote (and it's cousins) sounds trashy and awful (to me).

What I'd REALLY love is for someone to develop a way to change the firing order on the voodoo so we can run a true FPC.

 

[19-kilo]

Like any design project. I’m sure Ford had to make compromises. That said, i
Hope the Voodoo does ok. The new engine tuning that come out in ~2018 really smoothed out my 2016 build GT350. Tuning can help, but design compromises will be the limiting factor.

It’s still the coolest and most unique car I have ever driven/owned (And that includes Porsche GT4, BMW turbo inline 6, zl1 Camaro 6.2L) , even the new GT500 predator ) all are less exciting than the GT350R.

 

[dpAtlanta]

I LOVE my Flat Planed Crank VooDoo, and have enjoyed all of the trouble-free 40,500 miles I have put on the odometer since purchased new in August of 2019.

I shall continue to rack up the fun miles while entertaining myself as I read doom and gloom tales that some tout that the VooDoo is unreliable, bad design, etc.

Keep it up Nay-Sayers… you’re keeping me entertained…!

 

[Angrey]

I LOVE my Flat Planed Crank VooDoo, and have enjoyed all of the trouble-free 40,500 miles I have put on the odometer since purchased new in August of 2019.

I shall continue to rack up the fun miles while entertaining myself as I read doom and gloom tails that some tout that the VooDoo is unreliable, bad design, etc.

Keep it up Nay-Sayers… you’re keeping me entertained…!

The biggest detriment isn't the NVH or vibes. It's 12:1 compression on pump 93. If you're on E85, few worries. If you're on 93, it's just a matter of time before bad fuel smokes the motor. Some guys get lucky, many aren't so lucky. The Gen3 added DI to combat against knock.

I'm not selling my Voodoo. But it'd be foolish not to admit that it's not optimal.

 

[Hack]

No I believe he’s referring to a quote from one of the GM engineers talking about how they figured the heavy vibration of the Voodoo was either a design issue or because of the UDDU crank order, and that they wouldn’t have to contend with the same issue. Then on the engine dump they kept having a loose oil filter and couldn’t figure out why until they did a slow motion video and saw the engine shaking the filter loose even with the UDUD firing order.

Think this is it, from Jordan Led
https://www.corvetteblogger.com/202...using-havoc-on-early-lt6-development-engines/

A lot of tasks seem easy when you are on the outside looking in. It never ceases to surprise me how many people seem to think they are smarter than everyone else and they never would have made this or that mistake. Pretty big of Jordan to admit he was arrogant and wrong after the fact.

I wonder if given enough time the aftermarket will sort out the voodoo engines since ford apparently just didn't have enough time and resources available to get it done the first time.

i'm not joking, sounds like they had a budget while GM had a blank check... or maybe we're just gonna see the same issues with that one since htey only increased the displacement over the voodoo.

The best way to sort the "issues" is to go to an entirely different engine. The biggest problems IMO are bore vs. stroke. Voodoo has too long of a stroke and too small of a bore, so piston speeds are too high. I agree GM's way was a much better way to go, but Ford had to make a hotrodded Coyote on a budget rather than going with a blank slate to meet their goals. They did save a lot of money on the front end by making slight mods to the Coyote rather than going blank sheet. And the Voodoo is definitely a big improvement over the Coyote from a performance standpoint.

SNIP

To be honest, if Ford didn't go to the god awful sounding flathead firing order in the coyote/variants, I'd say give me the CPC all day. But the drop from voodoo all the way to the trashy CPC offerings is substantial. The 4V modulars sounded magical. The coyote (and it's cousins) sounds trashy and awful (to me).

What I'd REALLY love is for someone to develop a way to change the firing order on the voodoo so we can run a true FPC.

So you like the 4.6 but not the Coyote? Wow, you really lost me there. IMO the 4.6 is the worst boat anchor ever created.

You could just buy a custom crank and cams for the Voodoo if you want "true FPC". But you should really have split intakes and equal length headers as well.

The biggest detriment isn't the NVH or vibes. It's 12:1 compression on pump 93. If you're on E85, few worries. If you're on 93, it's just a matter of time before bad fuel smokes the motor. Some guys get lucky, many aren't so lucky. The Gen3 added DI to combat against knock.

I'm not selling my Voodoo. But it'd be foolish not to admit that it's not optimal.

I think you mean 91, right? 93 isn't even available in some areas of the country. I ran 93 when I could, but there was no 93 near the track when I tracked mine. No problems on track running 91 for me. It wasn't a 100+ degree day or anything, but it was 70s or 80s.

 

[AvalancheSVT]

The best way to sort the "issues" is to go to an entirely different engine. The biggest problems IMO are bore vs. stroke. Voodoo has too long of a stroke and too small of a bore, so piston speeds are too high. I agree GM's way was a much better way to go, but Ford had to make a hotrodded Coyote on a budget rather than going with a blank slate to meet their goals. They did save a lot of money on the front end by making slight mods to the Coyote rather than going blank sheet. And the Voodoo is definitely a big improvement over the Coyote from a performance standpoint.

you're probaly not wrong. imo they should've made the engine smaller to get those slug sizes and the distance they travel down.

So you like the 4.6 but not the Coyote? Wow, you really lost me there. IMO the 4.6 is the worst boat anchor ever created.

my cobra was badass, dude, idunno what you're talkin about lol

 

[460Fred]

I keep hearing the budget constraints Ford had with the GT350 engine. Makes complete sense they would do that for a very limited production vehicle. GM has probably already sold more C8’s the last couple of years than Ford sold from ‘15 to ‘20 for the GT350/R.
Who’s going to be the first to put a C8 Z06 motor in a GT350

 

[wingnutt]

Who’s going to be the first to put a C8 Z06 motor in a GT350

1
2
3

…NOT IT!

 

[Inthehighdesert]

What manufacturer engineering department do you work in? It seems to me that so many have all the answers and a major business opportunity is escaping them by not jumping in to the pool and marketing a fix to all the shortcomings of the voodoo.

It was a dumb decision. The entire point of going flat plane instead of cross plane is to eliminate the heavy counterweights on the crank shaft. You do that knowing it's going to cause secondary rocker vibrations, but you're willing to live with the secondary vibes because....racecar and the lighter crank shaft will help you rev faster and the even exhaust pulses will help everything from scavenging to cylinder temp uniformity.

What Ford did was get halfway into that path and say "well, we don't want it to sound like a ferrari so we're going to change the firing order" to which someone said "yeah, but now we have BOTH primary AND secondary imbalance" and then someone said "well, just put counterweights on the crankshaft."

Furthermore, the secondary benefit of even exhaust pulses was corrupted when to enhance the sound further, they gave an unequal weird 3 into 1 and 2 into one header design.

And we still have to deal with the secondary imbalances of a large motor, which requires extra weight and dampening (weights on the trans, weights on the exhaust) as well as all the latent issues (like oil filters backing off).

As Honey Badger has demonstrated, while the voodoo is great, it's just not suited for long harsh use, the vibrations end up problematic in a number of areas.

Do I love the sound of my voodoo? Absolutely. Is it worth all the detriment? That's only a question each individual person can answer.

I didn't realize that the crankshaft was essentially a CPC crankshaft flattened out until after I bought the car.

To be honest, if Ford didn't go to the god awful sounding flathead firing order in the coyote/variants, I'd say give me the CPC all day. But the drop from voodoo all the way to the trashy CPC offerings is substantial. The 4V modulars sounded magical. The coyote (and it's cousins) sounds trashy and awful (to me).

What I'd REALLY love is for someone to develop a way to change the firing order on the voodoo so we can run a true FPC.

 

[Inthehighdesert]

Give it a little time. The experts will be out posting how GM screwed up on that motor design as well.

I keep hearing the budget constraints Ford had with the GT350 engine. Makes complete sense they would do that for a very limited production vehicle. GM has probably already sold more C8’s the last couple of years than Ford sold from ‘15 to ‘20 for the GT350/R.
Who’s going to be the first to put a C8 Z06 motor in a GT350

 

[AvalancheSVT]

Give it a little time. The experts will be out posting how GM screwed up on that motor design as well.

this is what i'd put my money on. ferrari doesn't make FPC V8's this big for a reason and they make more of em than anyone.

 

[50 Deep]

Like any design project. I’m sure Ford had to make compromises. That said, i
Hope the Voodoo does ok. The new engine tuning that come out in ~2018 really smoothed out my 2016 build GT350. Tuning can help, but design compromises will be the limiting factor.

It’s still the coolest and most unique car I have ever driven/owned (And that includes Porsche GT4, BMW turbo inline 6, zl1 Camaro 6.2L) , even the new GT500 predator ) all are less exciting than the GT350R.

The R is definitely a "combo breaker". Everyone seems to reminisce over this car.

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