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I am looking at the possibility of trying to change the about 70/30 split front/rear power split
my question is would changing the central differential in the transmission allow for a more centered power distribution such as 50-50 front to rear
 

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No, you need to control the haldex manually if you want to customize how power is sent to the rear. I've had the whole drivetrain apart and seen how it works. Power is sent from the engine through the transmission which the open front diff is inside. This biases the torque between the front two wheels. The output of the transmission is directly sent to the angle gear which is directly sent to the haldex which engages to a variable degree, controlling how much is power is sent to the rear diff which then biases the power between rear wheels. Changing the front diff will not affect how much power is sent to the angle gear from the transmission output (front diff). I used to think differently because of people who don't know what they're talking about on this forum until I had it apart and saw that the passenger axle travels through the angle gear, through the color sleeve and through the transmission output (front diff) where is mates internally to one side of the front diff. The collar sleeve is mated to the entire front diff so as the whole ring gear of the front diff spins, the collar sleeve -> angle gear -> and driveshaft to the rear spin. Hope that makes sense.
 

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What? It is 50/50 split if Haldex is engaged. Look at the gear ratios and how powertrain works.
Both angle gear and rear differential have same gear ratios.

If you want overdrive, you must install EUCD (P3 chassis) angle gear. And no, it is not at all plug and play.
 

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If you want overdrive, you must install EUCD (P3 chassis) angle gear. And no, it is not at all plug and play.
Didn't know P3 angle gears were overdriven ratio. Too bad none came with an M66.
 

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Didn't know P3 angle gears were overdriven ratio. Too bad none came with an M66.
They are overdriven on a P2 chassis car if installed. On P3 AWD cars, the ratios are equal between axles.

There are many P3 chassis cars with M66 transmission. US market didn’t get any?
 

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They are overdriven on a P2 chassis car if installed. On P3 AWD cars, the ratios are equal between axles.

There are many P3 chassis cars with M66 transmission. US market didn’t get any?
I just spent an hour or so looking I do not believe any US cars with the newer style angle gear came with an M66, the early ones all had a TF80. I'm going to double check VIDA. But point being, if there was already a collar sleeve out there to adapt M66 to new style angle gear it would be cool to play around with.

Sent from my ONEPLUS A6013 using Tapatalk
 

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They are overdriven on a P2 chassis car if installed. On P3 AWD cars, the ratios are equal between axles.

There are many P3 chassis cars with M66 transmission. US market didn’t get any?
Last Manual Volvo was 2008 R ... after that all Autotragic.
 

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09 V70 D5 from Europe came with an M66 and AWD.
White Daytime Calm Line Sky

Angle Gear: 36002479
Collar Sleeve: 31325358


Same same angle gear was used in US Market 2007-2011 S80, 2009-2011 XC60, 2008-2011 XC70, 2008-2009 V70, and 2011-2012A S60 according to VIDA.

If I ever see one I would buy it and at least compare ratios and maybe see if it even fits. Would probably need a new driveshaft to the rear. Probably just a pipe dream but that would be pretty sweet to have Focus RS - like AWD.
 

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OP, haldex is realtime 4WD. It's always getting some bit of power sent to the rear wheels. When the computer detects slippage, or enough traction demand*(mashing the go-pedal, cornering, etc) it'll lock up the haldex diff, so that the rear differential is getting more power sent through it.


*I'm pretty sure only the Rs do this, but I could be wrong. It was tied into the 4C system, so that it would do some light torque vectoring based off of the various sensors around the car.

Sure, you might be able to trick the haldex diff into locking up more frequently, or more easily, but I'd imagine that won't be great for longevity.

I don't think there would really be a benefit in changing it. You'd probably have reduced fuel economy, and more wear.


***All of the above may or may not be completely, or partially false***
 

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I don't think there would really be a benefit in changing it.
Not for street only but if you want to take your R to the track and dial in the way it performs then yes there could be significant gains.
 

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I mean, you're never going to be able to reduce the power output to the front wheels to make the system rear biased. The front axle is mechanically connected to the engine, whereas the rear relies on a pump to control the level of slip, right?
 

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I mean, you're never going to be able to reduce the power output to the front wheels to make the system rear biased. The front axle is mechanically connected to the engine, whereas the rear relies on a pump to control the level of slip, right?
Right but if you look at what the C30 guys have done, some of them can manually control the haldex with an Arduino or whatever and theyve gotten some really good results. Also what contrast was saying is that P3 angle gears are a different ratio so if installed in a P2 car and the haldex is fully locked, the rear wheels would be spinning faster than the front wheels. This is the same strategy in the new Ford focus rs and how they're able to achieve the drift mode. Not that that would be my goal but this would be to possibly overcome the front drive bias of the car. You could play around with the haldex lock up, maybe like 70-80 percent would induce power on slight oversteer but not necessarily be as extreme as a "drift mode."

Sent from my ONEPLUS A6013 using Tapatalk
 

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Ah I think I get it now.

I'd wonder what adjusting it in the R would do. I'm assuming they're using an arduino to intercept and modify the signal. Again, I'm not 100% sure, but I think the R was a bit unique in that throttle demand and input from 4C could cause the haldex to lock up more. I could see the overdrive setup, that contrast mentioned, could cause problems, too.

But maybe not.

I feel that my R could be a bit better, but with IPD sways and KWs, it's got a fairly neutral balance on the whole over/understeer side of things. Off throttle, it'll understeer, but on throttle the back end feels like it wants to come out. But I suppose I have more weight in the back than you do.
 

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Ah I think I get it now.

I'd wonder what adjusting it in the R would do. I'm assuming they're using an arduino to intercept and modify the signal. Again, I'm not 100% sure, but I think the R was a bit unique in that throttle demand and input from 4C could cause the haldex to lock up more. I could see the overdrive setup, that contrast mentioned, could cause problems, too.

But maybe not.

I feel that my R could be a bit better, but with IPD sways and KWs, it's got a fairly neutral balance on the whole over/understeer side of things. Off throttle, it'll understeer, but on throttle the back end feels like it wants to come out. But I suppose I have more weight in the back than you do.
Yeah something like that, I've done a ton of digging on that subject but the people who have sucessfully done it are keeping quiet about it and there's some that got close but didn't iron out all the details. And yeah I think you're right. I think even in it's current form having it locked for track use would be worth experimenting with. I've also heard that even full lock is not truly full lock. I think actually fully locked is sort of harsh. I may be remembering that from a VW haldex video.

That's interesting mine is sort of the opposite, slight understeer on throttle and lift off oversteer. Hard to say without getting it on the track with the new suspension set up yet. Makes sense that it would be different with a VR though with more weight in the back like you said.
 

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Yeah, it comes out effortlessly in the snow(duh) and can come out fairly easily in the rain.

There's even an offramp near me that I'd even get some oversteer on with my snows. Scared me the first couple of times I hit it. Not a dangerous amount, but when you're used to no oversteer whatsoever, it was a bit of a shock.

For what it's worth, I'm around -2.4* of rear camber and have my toe set to 0 on both sides.
 

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09 V70 D5 from Europe came with an M66 and AWD.
View attachment 54601

Angle Gear: 36002479
Collar Sleeve: 31325358


Same same angle gear was used in US Market 2007-2011 S80, 2009-2011 XC60, 2008-2011 XC70, 2008-2009 V70, and 2011-2012A S60 according to VIDA.

If I ever see one I would buy it and at least compare ratios and maybe see if it even fits. Would probably need a new driveshaft to the rear. Probably just a pipe dream but that would be pretty sweet to have Focus RS - like AWD.
What I'm interested is in a beefier angle gear as I need to change mine soon (still works but the splines are thin). Both the one you mentioned and the one for TF80SC are better than mine but could not find any definitive answer if there is a collar sleeve for M66 to work with the TF80SC one. I can get the parts from Eu but only if they actually fit. Do you know?
 

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Yeah, it comes out effortlessly in the snow(duh) and can come out fairly easily in the rain.

There's even an offramp near me that I'd even get some oversteer on with my snows. Scared me the first couple of times I hit it. Not a dangerous amount, but when you're used to no oversteer whatsoever, it was a bit of a shock.

For what it's worth, I'm around -2.4* of rear camber and have my toe set to 0 on both sides.
Nice haha yeah I was turning onto an onramp the other day and came in a little hot and had to lift off the throttle and the whole rear end swung out it was pretty fun! Would love to get that on throttle but I bought the wrong car for that.
Do you have the camber bushings? Mine is probably more than that I'd have to look.
 

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What I'm interested is in a beefier angle gear as I need to change mine soon (still works but the splines are thin). Both the one you mentioned and the one for TF80SC are better than mine but could not find any definitive answer if there is a collar sleeve for M66 to work with the TF80SC one. I can get the parts from Eu but only if they actually fit. Do you know?
I don't think there is one. I don't know for sure but from what I've read no one found one.

http://v70r.com/forums/topic/13041-p2-awd-collar-gear-analysis/?page=3

You could take a gamble on that p/n I listed up there but that angle gear probably won't bolt right up and is probably a different gear ratio according to contrast.

I'd just get a used angle gear, one from erie vovo with that lifetime warranty they have.
 
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