MS6 AWD System

[DSMConvert]

and before anyone even thinks of saying this is a Haldex system(which is where most people make quotes that it can deliver 50/50 in corners) read the following link...post #20...directly out of Haldex Inc. tech support. You'll need to insert the forum name (cough...m.a.z.d.a.6.c.l.u.b.com...cough)

http://forum.***************/index.php?showtopic=54297&hl=haldex&st=15

The below link was put together by crossbow for general information about the ms6 awd system(Toyoda)...

 

[Speed6 Guy]

DSMConvert You should know by now that we dont allow links to other forums here so I had to edit your last post.

Moreover I do think that Crossbow has a lot of good points. I may have been a little quick to say BS anything. My apology but when I drive my car it does not handle like there is only 10% power to the rear wheels. So what I am saying is maybe there is more going one (or less going on) then you may think. I would just like to see the testing that you have obviously done so extensively put on the forum. I can understand that there are a lot of misconceptions with the Mazdaspeed6 (like the Halidex thing) that are going around I just dont want there to be any more of them so show the facts about the AWD system and then I will understand where you are coming from.



Also stop asking for your threads to be stickied.

 

[ottawaP5]

DSMConvert You should know by now that we dont allow links to other forums here so I had to edit your last post.

Moreover I do think that Crossbow has a lot of good points. I may have been a little quick to say BS anything. My apology but when I drive my car it does not handle like there is only 10% power to the rear wheels. So what I am saying is maybe there is more going one (or less going on) then you may think. I would just like to see the testing that you have obviously done so extensively put on the forum. I can understand that there are a lot of misconceptions with the Mazdaspeed6 (like the Halidex thing) that are going around I just dont want there to be any more of them so show the facts about the AWD system and then I will understand where you are coming from.


Also stop asking for your threads to be stickied.

I have to agree with you on this...when you take this car around a corner quickly it feels as though there is a lot more than 10% at the rear wheels.

 

[DSMConvert]

hmm...yea i knew I wasn't supposed to post links...I just didn't see another way to get the info over here without directly copying and pasting it. It's crossbows thread so I would prefer to get his permission before stealing it for another forum...

Hehe I didn't ask for this thread to be stickied...I just offered to invest the time into an awd fact thread if it would be stickied... Just seems pointless though to invest all the time into a thread only to have it fall to the 2nd page by the end of hte week, and have the question asked 4 more times...

There really isn't any testing I can do that hasn't already been done. My information comes directly from engineers who designed the setup.. Its like asking someone to provide proof that when you jump off a roof you fall towards the ground...its just basic mechanics...the proof is in the diagrams... In this case there is no vc or center diff so it would be impossible for a single output drive train to transfer power at 2 different speeds...in a vc/center diff system they can do this through the slippage that takes place in the viscous coupling..thus it can spin the front wheels at 350 rpms while spinning the rear wheels at 250 rpms(note the numbers are solely for example). In a true awd system the output from the engine first goes into a xfercase(which most of the time contains a vc). the xfercase breaks this single input into 2 separate outputs, thus allowing each axle to turn at its own speed... In our system we have a single output the merely engages and disengages itself to the rear...think of it like a spinning tire...if you grab the tire what happens? If you get a firm grip you begin spinning at the same rate as the tire. If you don't your hands slip and you burn them up... same way with the electronic clutch packs on the ms6, it either gets a firm grip and turns at the same speed as the front, or it slips(if this DID happen it woudl burn up the clutch back in a heartbeat, which is why it cant make the rear wheels spin at a different rate). A VC's sole job is to allow that slipping without burning up, which it accomplishes with fluidic friction, much like a torque converter.
On the apology note I apologize myself if I came off gruff...I just get tired of being called out all the time, when I end up being correct. I try very hard to not make posts without having my facts straight and/or doing my own research, and most people either A. know my reputation for posting information or B. At the very least give me the benefit of the doubt and do their research before saying im full of it...

Anyways I'll get ahold of crossbow and get his permission to post the awd diagram out of the mazda service manual...I think it will help alot to see a picture of how things are connected...

 

[TheDutchGun]

From what my buddy tells me(he has an MS6), is it not basically fwd with a little help available from the rear wheels when necessary?

 

[Klip]

Not exactly sure about this +1 or +5 stuff but here it goes:\

+10 to DSM for trying, I hear yah.(inout)

 

[wannabe]

if there is only 10% going to the rear wheels then how am i able to spin the car so easily on the stock tires in the snow? if i pull out onto snow, cut the wheel and gun it, the backend just spins right around. theres a video i saw on youtube of a dude doing donuts in it...thats not possible in a 90% fwd vehicle....at least not by the laws of physics...

 

[Karma_hunden]

Im too lazy to comment on all this but i'll say this...about 2 weeks ago i rotated my tires and the rear tires where more worn out that the ones infront...you do the math.

 

[jtom]

Wow thanks for all the replies. I knew the ms6 would have front bias.

 

[DSMConvert]

well I can't explain that karman...all I know is what the engineers and diagrams say..BUT another way you can tell is to go out to a wet parking lot and see if you can do an axis spin...if the power to the rear is over 40% you will be able to do a perfect axis spin. Axis spin - where the center of the car stays fixed and both ends rotate around it..

 

[Gandalf]

hmm...yea i knew I wasn't supposed to post links...I just didn't see another way to get the info over here without directly copying and pasting it. It's crossbows thread so I would prefer to get his permission before stealing it for another forum...

Hehe I didn't ask for this thread to be stickied...I just offered to invest the time into an awd fact thread if it would be stickied... Just seems pointless though to invest all the time into a thread only to have it fall to the 2nd page by the end of hte week, and have the question asked 4 more times...

There really isn't any testing I can do that hasn't already been done. My information comes directly from engineers who designed the setup.. Its like asking someone to provide proof that when you jump off a roof you fall towards the ground...its just basic mechanics...the proof is in the diagrams... In this case there is no vc or center diff so it would be impossible for a single output drive train to transfer power at 2 different speeds...in a vc/center diff system they can do this through the slippage that takes place in the viscous coupling..thus it can spin the front wheels at 350 rpms while spinning the rear wheels at 250 rpms(note the numbers are solely for example). In a true awd system the output from the engine first goes into a xfercase(which most of the time contains a vc). the xfercase breaks this single input into 2 separate outputs, thus allowing each axle to turn at its own speed... In our system we have a single output the merely engages and disengages itself to the rear...think of it like a spinning tire...if you grab the tire what happens? If you get a firm grip you begin spinning at the same rate as the tire. If you don't your hands slip and you burn them up... same way with the electronic clutch packs on the ms6, it either gets a firm grip and turns at the same speed as the front, or it slips(if this DID happen it woudl burn up the clutch back in a heartbeat, which is why it cant make the rear wheels spin at a different rate). A VC's sole job is to allow that slipping without burning up, which it accomplishes with fluidic friction, much like a torque converter.
On the apology note I apologize myself if I came off gruff...I just get tired of being called out all the time, when I end up being correct. I try very hard to not make posts without having my facts straight and/or doing my own research, and most people either A. know my reputation for posting information or B. At the very least give me the benefit of the doubt and do their research before saying im full of it...

Anyways I'll get ahold of crossbow and get his permission to post the awd diagram out of the mazda service manual...I think it will help alot to see a picture of how things are connected...

First off I only asked you to prove your point - you don't need to get all offended.

Second you still have not done it. I don't know who crossbow is, or why he is the end all for info - but the post you linked and told us to read as gospel isn't even correct. It's already been proven that the car IS NOT 100/0 until slippage occurs. The Mazda promo vid with goes into the fact the car is always to some extent AWD, even if its only 85/15 when just going forward at speed. The only time its 100/0 is creeping along at 5mph. So I basically read a post that starts with incorrect info, why would I keep reading? (although I did)

Next - you say you talked to the engineers who built the system? What languages do you speak? Cause they certainly aren't here in the US. If you know them so well then why did we have to get Haldex's word that they did not build this AWD system? Couldn't you have told us this? I hate name dropping. Also you say the center clutch can't cause the wheels to rotate at different rpms. . .it's a PWM (pulse-width modulation) singal input going into a rear diff, a beefed up version of the RX8 diff. Whats the point of a beefy rear diff if I only ever get 10% of my hp in a turn? Even Mazda is not stupid enough to spend the $$$ on such a complex rear diff in a car that will never use it - if that was the case we would not have even gotten a rear diff - there is no point (even in a drag launch it will barely help). They could have saved a ton on production costs here (and they would have).

Also, you are being too generic. You can't simple state "in a turn" you only get 10% rwhp. What steering angle? So when I change lanes I'm really basically FWD? If its a full lock turn then yes, I could see it limiting the rear to some extent - but I would bet its based on speed and steering angle. Cause I have certainly taken a fun U-turn and gotten the backend around. If you know these engineers so well get s some schematics and AWD control module info that goes into steering angle/yaw/wheel speed sensor and how they calculate the amount of rwd bias. THAT would be useful.

 

[Speed6 Guy]

+1 But lets not get too out of hand.

 

[Gandalf]

Also - if anyone has the autoenginutiy scan tool with the optional Mazda CAN add-on they website says it can read things like PWM AWD rating, all 4 wheel speed sensors, and a few other very key sensor reading that would be actual proff of what is going on. I will have this tool in a month or so (tax return) and will be happy to try and capture some real world data to either prove/disprove our current discussion. But if someone already has it perhaps they could help us?

 

[jred321]

All Sti's have that ability. It's the only Subaru model that has that though. On Sti's its called DCCD (driver controlled center differential).

that's not the function of the DCCD. the diff in the sti is either 35/65 split or 49/51 depending on year. the DCCD controls how it locks up when slippage is detected, just like the ACD on the evo but it uses more sensors to make it slightly more complicated. the settings do not change torque distribution though

http://forums.nasioc.com/forums/showthread.php?t=932701&highlight=sti+dccd+torque+bias

 

[DSMConvert]

Gandalf tried to post the schematics...forum rules prevent me from linking to other websites....BUT if you bother to research the subject before posting wrong information about it you'd stumble upon another forum where you would see at 7 pages of the awd schematics, including all sensor layouts, hardparts, and control situations.

You don't know crossbow..and your point? If you knew as much about the ms6 platform as you thought you did then you surely would of come across crossbow on one of several forums. His contributions in regards to technical knowledge are astounding and well known among true tuners.

I speak german, of the 30 employees working for me, 3 speak fluent german, 2 speak italian, and half speak spanish. Want me to get all their signatures notarized that they speak those languages? b/c gee I wouldnt want to say something without having iron clad proof that you demand. I could also scan my german consolate passport for ya?

I love how quick you are to dismiss my claims and post your own without bothering to back yours up, yet you attack me? Wheres your proof. Oh wait thats right you jumped on the bandwagon. and its what you heard. Go get an engineering degree, become certified in all 9 areas of ASE, start a performance company then come talk to me about awd systems and how they work.

Not sure what you meant by your whole Haldex comment??? Several people called to ask them and they told everyone one of us that they did not build the ms6 awd system? This was the first step in finding the information, once haldex was determined not to have made the sytem it eventually led to Toyoda...I'm confused you yell at me for asking haldex to get solid proof, but when i lack it you attack me also????

My contact at Toyoda Machine Works, Inc - Junjii Ando's group(which speaks perfect english by the way. Never claimed I was buddy buddy with them, but I do have the understanding and knowledge to have a technical discussion with the engineers and be able to intrepret what they are saying. By the way do a search on this guys name and you'll see he's authored SEVERAL papers on awd systems developement.

So lets see I've given information on detailed schematics, direct contacts at Toyoda, as well as links to others input on the subject. I got all my ducks in a row.

YOUR TURN. I'm gonna go make some popcorn so take your time, but I'm not going to post anymore on this. Either people will choose to beleive what everyone says, or they'll take a look at information for themselves and draw their own conclusions. This is EXACTLY how this stupid haldex rumor got started...a bunch of idiots posted up what they thought was correct, b/c they read it in a magazine and bam...took over 6 months and a half dozen threads for the damage to be fixed.

Ok I'm posting this diagram...its the only way to solve this argument without it getting any uglier. Gandalf read the very last document entitled AWD operation...paying attention to the straight line condition and the tight turn condition. Notice it says it reduces the power to the rear wheels to prevent bindign...so if we deduct that the max is 50/50 and you reduce that 50 to the rear wheels...well do the math means you aren't getting anywhere near 50% to the rear...

To keep from getting banned I've removed part of the link name. ("mfg, the number 6 and what type of card you have to have to race a nasa event all as one word).

http://forum.*********.com/about4221.html

 

[Gandalf]

I am not going to quote since the posts are getting long. I have read that diagram - and have yet to find the number 10% anywhere on it. You will also notice the title of the paragraph you are quoting says "Tight Cornering Control" - and it says it is based on wheel speed sensors and steering angle sensors. What it does not state, as you do very matter of factly, is that anytime you turn it limits rear bias to 10%.

Even your above post - which is basically a long page telling me I don't know what I am talking about, yet giving no facts - doesn't prove anything. There are a lot of sensors involved in this AWD system. It seems to me that such a knolwedgeable tuner as yourself would have the means to log these sensors. So give us some logs. Show me a graph of steering angle vs. wheelspeed vs. rear bias. Simple right?

I don't want papers or numbers or "well so and so told me" about just ANY AWD system. I want them for THIS CAR. Why is that hard to understand? You get very angry when someone questions your unfailable knowledge of cars - we don't know you from Adam, so why would I take anyone's word on an internet forum as the absolute truth when they have no numbers to back up their claims? I understand the concept of wheel speed and binding and yes I realize the limitations of a part-time AWD system, so I know we don't get all 4 wheels at max pull in a corner - but where do you get your 10% number?

 

[jdub260]

+1 But lets not get too out of hand.

I remind everybody please let's keep this a civil conversation. I'm sure that we all want the truth here, but character attacks are not gonna get us there.

Why don't we let it simmer and wait for Gandalf, or anybody else that has one, to get his autoenginutiy scan tool and see what kind of numbers he/they get out it. This way there is documented proof and everybody wins.

Remember we all want the best for the MS6 community. Don't we??

 

[Gandalf]

I already know I am partially wrong. And DSM's points are well founded. I simply want him to give us some numbers and stop acting like everyone should just believe him cause he knows everything - its annoying. He is also spouting a 10% number that has no basis except from some other post (that also has no real world numbers) yet then goes right around to tell us to stop jumping on the bandwagon of "something we heard" - which is exactly where he is getting his 10% number.

A better picture to link would be the rear LSD diagram that states right away the rear LSD is there for improved straight-ahead performance. No mention of cornering - which I doubt is an unintentional omission.

 

[DSMConvert]

Edited out the first paragraph of this response, since I submitted it after 2 additional posts were made, to remain civil as requested by the mods. Gandalf I apologize for the above attacks to yoru character.

But I will clarify my 10% claim, since I do need to be a little more specific...the amount of reduction to the rear output is a function on the turn angle/yaw/pitch sensors. So on long sweepers you'll have little to know reductions...but in tighter corners say for instance an auto-x event or emergency maneuver, that reduction will be significant. When I did the "math" and looked at the diagrams I came up with what I thought was a good guestimate of the amount of power able to be transferred(originally my number was more around 20%). Afterwards I conferred with other members as well as engineers in the field of driveline mechanics and came to the generalized 10%, though I will admit it shouldn't be taken as an exact number, but more of a ballpark.My apologies if I misconstrued my words, but I consider a turn something over 60 degrees of center, which is where you would begin to see a significant power reduction. If you do the equations regarding fluid mechanics( to determine temps b/c if you notice the awd system completely shuts off power when a certain temp is reached) you'll notice that as the temp rises you need to decrease the length and increase the freq of the pulses from the electric clutch. Which in turn reduces the amount of power that can be transferred between the 2 sections...

For example lets say that durning straight line driving where the wheel speeds can match for the majority of the time the clutch pulses 100 times for 2 seconds per pulse(time of actual engagement). Now if you try to do this in a hard 90 degree corner you're rear wheels will want to turn at a different rate from your front ones. Now obviously something as go to give to prevent driveline binding...in this case the clutch does the giving. well if we keep the same pulse freq/width we are no doubt going to build up significant heat from the force of the 2 shafts attempting to spin at different rates. so to combat this the clutch speeds up the freq and decreases the width(the amt of time the 2 pieces are actually connected) which in turn means the 2 shafts are connected less on each pass. Meaning less power transfer.

Lets make an example. Go find a giant tractor tire and do the following. On the first move I want you to push it as hard as you can 100 times, but only actually touching the tire for 2 seconds each time. Now on the second move I want you to push 250 times but only touch the tire for .5 seconds. Let me know which one moves the tire further......

And not to be rude, but I dont have the time to prove myself to every new member who questions my answers simply b/c they dont know me. People either A. Trust that I am providing accurate information as I have done in the past knowing that my reputation speaks for itself, or B. go out and do the research/testing for themselves and find out I was right to start with. Im sure that the members that do know me, will attest that I rarely make statements without having looked into first-hand. To get the requested info you want, simply to show you that I'm right, would require numerous hours of time that I don't have right now. I wish I had the free time to throw up graphs and logs, as I love sharing information I've found with others.

 

[Hate]

if there is only 10% going to the rear wheels then how am i able to spin the car so easily on the stock tires in the snow? if i pull out onto snow, cut the wheel and gun it, the backend just spins right around. theres a video i saw on youtube of a dude doing donuts in it...thats not possible in a 90% fwd vehicle....at least not by the laws of physics...

Because the stock tires are summer only tires and not meant to be driven in snow AT ALL?