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Discussion Starter #1
I just rolled over 500 miles and I have to say "Great job" on my 2012 Mustang GT. I'd say she's fully broken in now and so far it's in my top three cars owned, but I have one suggestion. I traded in a 2005 Dodge Magnum RT that I put 75k miles on. The 5.7L Hemi had the MDS on it. If you don't know in laymans terms that's cylinder deactivation. As it is the Coyote 5.0 is a great engine, but I think if it had cylinder deactivation it would be a stupendous engine. I know you're all into Eco-Boost now, but with cylinder deactivation you can keep your 8 cylinder motors and get the mileage of a turbo 6 if you'll just shut down 4 of the 8 cylinders occasionally. I'm telling you as a fomrer MDS driver it works and works well. Just my .02.
 

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I had a Dodge Ram with Hemi and MDS and it must've never functioned correctly because I never saw over 14 mpg's and I babied the crap out of it.
 

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Not even close! TiVCT has nothing to do with economy/gas mileage. TiVCT has to do with cam/valve timing being different at idle vs. red line.
 

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Discussion Starter #5
I had a Dodge Ram with Hemi and MDS and it must've never functioned correctly because I never saw over 14 mpg's and I babied the crap out of it.
MDS is conditional. If you were constantly city driving you would see MDS less than 10% of the time.
 

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MDS is conditional. If you were constantly city driving you would see MDS less than 10% of the time.
Must've been what happened I guess, although on Interstate trips I only got about 16-17mpg at most. Oh well, it was a great truck but I'm much happier with my 5.0!!!
 

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I don't want anything deactivating in my 5.0. I bought it to haul ass and not worry about fuel economy. The OP should have bought a V6.
 

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Nothing new there! Yes TiVCT optimizes fuel economy for EIGHT cylinders. Just think how great it would be if TiVCT shut down 4 cylinders when they were not needed. Just last weekend I was on a long stretch of flat Florida road with the cruise set at 70 mph. With little to no head wind the computer was reading 24.7 mpg. Not bad! However, under those conditions I did not need all eight cylinders buring gas to maintain. Lets say that IF the motor could have shut down 4 cylinders I could have seen 20% better gas milaege. That 24.7 mpg could have been 29.6 mpg. WOW!
 

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I don't want anything deactivating in my 5.0. I bought it to haul ass and not worry about fuel economy. The OP should have bought a V6.
Get a grip pal! I have the Coyote because I wanted it. However, I'm not blind to making things better when they can be!
 

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TiVCT lets the engine adjust cam timing to make it optimal for damn near any operating condition, RPM, or load. Other engines have to compromise with an in between grind or limited adjustment. That pays huge dividends in efficiency and fuel economy, along with negating the need for an external EGR system.

Cylinder deactivation really only makes more sense on V-8s that still use a single cam in block and pushrod activation, hence the LSx and Hemi engines using them. A DOHC motor would require quite a bit more complexity, cost, and weight to do this. The overall size would likely be greater, and a DOHC V-8 isn't all that small to begin with.
 

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TiVCT lets the engine adjust cam timing to make it optimal for damn near any operating condition, RPM, or load. Other engines have to compromise with an in between grind or limited adjustment. That pays huge dividends in efficiency and fuel economy, along with negating the need for an external EGR system.

Cylinder deactivation really only makes more sense on V-8s that still use a single cam in block and pushrod activation, hence the LSx and Hemi engines using them. A DOHC motor would require quite a bit more complexity, cost, and weight to do this. The overall size would likely be greater, and a DOHC V-8 isn't all that small to begin with.
Not true! MDS as well as GM's version works off of oil pressure and sliding hardware that's already there. It would just take more computer power and a bit more maching at the factory level.
 

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You do realize that those engines have half as many valves to actuate, right? An OHV arrangement also has a lot more room to work with, and they can be installed with very little overall changes needed. Most of those engines also don't have variable cam timing, something that further complicates controls since it can't be a simple on/off deal anymore depending on the valvetrain and piston to valve clearance. Lifters can be hydraulically actuated easily enough, it's much harder on a direct acting cam over valve arrangement with little room to encorporate that.

Pop a DOHC cam cover off, there is much less room for the double amount of actuators that would be required to control the valves on the deactivation cylinders. It'd require significantly more space and redesigning to incorporate them into those engines. It's useful in it's place, and nothing magical or complicated like you say. If it were beneficial AND feasible, it would have been done. I can guarantee that it was looked into during the concept validation phase.
 

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Discussion Starter #15
I got a grip pal. This is a Mustang, not a station wagon like you owned before.:nono:
What so you're saying the Mustang can't be better economically and a performance car too? Wake up and smell the coffee! It's 2011 and there's technology that can allow you to have both. If Ford gave the option of a 5.0 without cylinder deactivation and one 5.0 with cylinder deactivation 95% would buy the one with it. I say that because that's the current break down of Mopar's Challenger with the 392. However, there are other factors such as transmission. The manual 392 does not get MDS.
 

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dear gawd no way, this is in the chevy impalas lame for a muscle car
 

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Discussion Starter #18
You do realize that those engines have half as many valves to actuate, right? An OHV arrangement also has a lot more room to work with. Pop a DOHC cam cover off, there is much less room for the double amount of actuators that would be required to control the valves on the deactivation cylinders. It'd require significantly more space and redesigning to incorporate them into those engines. It's useful in it's place, and nothing magical or complicated like you say. If it were beneficial AND feasible, it would have been done. I can guarantee that it was looked into during the concept validation phase.
The actuators don't go under the valve covers. The sliding piece that stops the valves from opening/closing is the only hardware under the valve covers. In fact it would be the same hardware that would stop two intake valves and two exhaust valves as it would be for a set of one each. Honda has a cylinder deactivation system on its OHC V6 in the Odysee. If the Japs can do it . . ...
 

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Ah yes, the trans deal too. I forgot about that one. I'm not aware of any of these engines using this with a manual trans. I believe it makes it very hard to control and calibrate it when the driver is calling all of the shots as far as gear selection and clutch control. An auto trans vehicle can coordinate all of the functions with as much time as needed since it is really just a driver request when you mash the pedal for a downshift.

I'm not against it at all, it just is one of those things that is more feasible in some designs rather than others.

The actuators don't go under the valve covers. The sliding piece that stops the valves from opening/closing is the only hardware under the valve covers. In fact it would be the same hardware that would stop two intake valves and two exhaust valves as it would be for a set of one each. Honda has a cylinder deactivation system on its OHC V6 in the Odysee. If the Japs can do it . . ...
Once again, you are making this engine monstrous, and the OHC system is not as simple as one actuator as far as I know. The OHV system is very simple, but unrelated for this type of engine. And I still am not aware of anyone using this on a continuously variable independent intake/exhaust cam (TiVCT) setup. VTEC and the simple OHV setup are much simpler systems in operation and in design. Eventually valve to everything clearances would be an issue. I'm not saying it isn't possible. But what do you gain for the cost, size, and complexity? Just disabling cylinders doesn't necessarily mean better economy. There is far more testing involved in determining if it is actually a benefit for a given engine. The Honda system turns off a whole bank, so it would be used that much less than something with more flexibility.
 
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