MDS Already Bugging Me.

[MoToad]

Don't get me wrong. I love my new Ram. It's just that crawling around town in ECO mode I can both feel and hear it lugging along on 4 cyls. I just can't get it out of my mind that in the long run it just won't be good for it. I'm pretty old school and that always meant don't lug your engine. So I am sort of making it a point now of taking it out of ECO mode, at least for around town. Besides, trading in the old Tundra has improved the gas mileage no matter how you look at it.

 

[turkeybird56]

Just hit the manual gear mode on steering wheel up to 8th. Make it a habit if it bothers U, lol. I do when in town. On hwy, not so much as almost never in an ECO mode at 85 MPH on Interstate, lol. NOTE: ECO may not always indicate in MDS mode or not, IMHO...

 

[Docwagon1776]

LS swap it.

 

[kurek]

Nobody who understands the phrase dynamic compression ratio is in a hurry to delete MDS.

 

[Wild one]

Nobody who understands the phrase dynamic compression ratio is in a hurry to delete MDS.

VVT and MDS are 2 totally seperate entities,he's not trying to lock out the VVT,he just wants to disable the mds cylinder drop out

 

[NETim]

Whenever I'm in city type driving (<50MPH), I normally gear down to keep the revs up. No MDS nonsense going on and besides, the chicks dig it.

 

[Brandon-w]

Nobody who understands the phrase dynamic compression ratio is in a hurry to delete MDS.

If you understand how mds works and how many engines it's killed over the years you'd Wana delete it too. I've taken out two mds engines due to cam failure. Before anyone says anything my oc schedule was every 5k religiously.

 

[kurek]

Nobody said anything about vvt and the claim that MDS is related to lifter failure has been exhaustively and effortlessly swatted away by the existence of non MDS engines experiencing the same failure.

 

[RamRod37]

mds has not one thing to do with cam & lifter failures my truck being a HD is non

If you understand how mds works and how many engines it's killed over the years you'd Wana delete it too. I've taken out two mds engines due to cam failure. Before anyone says anything my oc schedule was every 5k religiously.

mds and had lifter failure and mine is not the only non mds hemi that has had same failure

 

[Wild one]

Nobody said anything about vvt and the claim that MDS is related to lifter failure has been exhaustively and effortlessly swatted away by the existence of non MDS engines experiencing the same failure.

MDS has nothing to do with increasing dynamic compression either,VVT does though.Find me something that says MDS affects dynamic compression.I'm guessing you've never done a running compression test either have you

Wallace Racing: Dynamic Compression Ratio Calculator

Calculators | UEM Pistons

www.uempistons.com

The static and dynamic compression ratio calculator

This calculator will calculate both the static and dynamic compression ratios of your engine.

www.gofastmath.com

 

[CanuckRam1313]

I've got almost 150,000Km's on my 19' Hemi and have, let's say for arguments sake, never, used the MDS feature. I personally can't stand it, and see no benefit whatsoever of having it on at any time while driving. It also doesn't afford any type of real fuel savings as far as I'm concerned.

The bogging/sluggish feeling at low speed/low load driving is unnerving! All V8, all the time is what works for me and my truck.

I run good fuel and premium synthetic oil with a premium oil filter and keep my OCI's tight.

While I don't idle my engine, I do drive on the highway and in-town a lot for my career, and I love to drive spiritedly where the VVT kicks in and revs right out until it changes gears on its own..lol

I've never had any issues with my engine not using the MDS during my whole ownership experience.

 

[kurek]

For a given throttle aperture if you cut the number of cylinders drawing from it in half you double the air available to the remaining cylinders. Dynamic compression at WOT is meaningless because MDS doesn't exist at WOT. Not really all that controversial.

 

[mikeru]

I realize the technology has advanced since 1981, and car companies have figured out how to do cylinder deactivation. But I'll never stop thinking of this disaster any time anyone mentions MDS, or any other form of it. I still remember watching tv commercials for this and thinking that's a bad idea even back then when I was only 17 years old...

The Impossibly Disastrous 4-6-8 Cadillac Engine Of 1981

A comedy of errors is all you can call Cadillac's 4-6-8 cylinder deactivation engine.

www.motorbiscuit.com

 

[Wild one]

For a given throttle aperture if you cut the number of cylinders drawing from it in half you double the air available to the remaining cylinders. Dynamic compression at WOT is meaningless because MDS doesn't exist at WOT. Not really all that controversial.

Not quite.If you have 1/2 the cylinders pulling in air,you also have 1/2 the manifold vaccumn to work with.When MDS kicks in,cylinder pressure in the non-mds cylinders does not go up in relation to what it would be if mds wasn't engaged

 

[kurek]

Not quite.If you have 1/2 the cylinders pulling in air,you also have 1/2 the manifold vaccumn to work with.

JFC I'm gonna just let you think about that one for a little while.

 

[kurek]

I realize the technology has advanced since 1981, and car companies have figured out how to do cylinder deactivation. But I'll never stop thinking of this disaster any time anyone mentions MDS, or any other form of it. I still remember watching tv commercials for this and thinking that's a bad idea even back then when I was only 17 years old...

Imagine judging every product of industry this way.. or why only MDS specifically and not transmissions, fuel injection, tires, nav (you don't need to figure out how to fold your android auto maps like a 1981 map...) ..

Just specifically MDS. For some reason.

 

[Zoe Saldana]

Don't get me wrong. I love my new Ram. It's just that crawling around town in ECO mode I can both feel and hear it lugging along on 4 cyls. I just can't get it out of my mind that in the long run it just won't be good for it. I'm pretty old school and that always meant don't lug your engine. So I am sort of making it a point now of taking it out of ECO mode, at least for around town. Besides, trading in the old Tundra has improved the gas mileage no matter how you look at it.

Put it in Tow/Haul. I do it all the time.

 

[Wild one]

JFC I'm gonna just let you think about that one for a little while.

Yea i think you better read the links i posted about how to calculate dynamic compression ratio,mds "does not" affect cylinder pressure in the non-mds cylinders. i'll let you think on that one after you figure out how dynamic compression is calculated,which it appears you don't know how it's calculated Find me something that says mds is a factor in calculating dynamic compression ratio increases

 

[kurek]

Show me on those calculators where to enter throttle aperture.

 

[Wild one]

Show me on those calculators where to enter throttle aperture.

View attachment 531484

Show me a calculator that calculates dynamic compression ratio increases at part throttle.You won't find one,as it's impossible to calculate a part throttle compression ratio increase.Stick a compression testor in a running engine and you'll see that