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Discussion Starter · #1 ·
FYI, I got this off the MS3 forum when asking about JBR parts



The RS's rear diff is not capable of handling any real extra power, maybe only another 30-40 hp at the crank. The driveline was optimized to the engines specific power output for weight savings. PM me for specific questions on the RS platform, I work in Ford Performance
 

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FYI, I got this off the MS3 forum when asking about JBR parts
That may be true, if you are looking at from Ford's official standpoint. Especially when they need to consider how the car can last 100k miles plus when designing components. Can the RDU handle more power? Yes. Can it handle it for 100k miles when you don't even drain and replace the fluid for the clutch packs? Who knows right now.
 

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I just read an article about the car on trackmustangsonline.com titled "Keep Your Mustang!". Its a pretty in depth look at the car from a mechanical and functionality standpoint and they said that the diff is pretty damn small along with some other disconcerting observations when the vehicle was taken apart. Worth a read all be it a sad one. I am still eagerly awaiting the car and will be so extremely happy with it though. Its a brilliant car.
 

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I just read an article about the car on trackmustangsonline.com titled "Keep Your Mustang!". Its a pretty in depth look at the car from a mechanical and functionality standpoint and they said that the diff is pretty damn small along with some other disconcerting observations when the vehicle was taken apart. Worth a read all be it a sad one. I am still eagerly awaiting the car and will be so extremely happy with it though. Its a brilliant car.

Small doesn't mean weak.. People swap out evo X diffs for evo 8/9 diffs because they're so much stronger. Checkout the difference in the size of those.. Auto part Suspension part Suspension Transmission part Automotive engine part
 

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When will all this hearsay stop!!!!!!!! When the first diff goes then we can all talk about it but until then people need to stop spreading rumors. I would love it if the first weak point was a driveshaft or something just to rub it in all these so called inside engineers. Every vehicle has weak points, even full on race cars, the fact is these claims are extremely exaggerated. 30-40 crank, we are pushing 50+WHP with no issues(very easy to get power BTW). The Diff which is actually a spool (reason for being compact and very smart move) only take power from the front and only takes what is programmed. The RDU is basically self protective until some one unlocks the module, you can add all the power in the world but the RDU will only use up to it's specified TQ limits at that given moment.
 

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Discussion Starter · #11 ·
When I told him about tune+ and whatnot



Im not sure I understand, yes, people are making 30-40 hp gains. that is the limit of what the rear diff can safely handle, anything else is a ticking time bomb. Additional diff cooling could be an answer for moderate power bumps and track driving
 

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FYI, I got this off the MS3 forum when asking about JBR parts
So he works for FP but doesn't know that the RS doesn't have a rear differential?
 

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So he works for FP but doesn't know that the RS doesn't have a rear differential?
That was what I caught as well. All these internet FP employees floating around, but don't know the car's components yet when it has been on the streets since February in Europe?
 
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That was what I caught as well. All these internet FP employees floating around, but don't know the car's components yet when it has been on the streets since February in Europe?
The only problem I have with this is the 3-4 page arguments over a Spool vs Diff and how it went no where( I think I enlightened many on what a spool actually was). Many people refer to the rear end as a diff, this is common in the automotive industry. From and engineer though, that is kind of a tough one as you should be emphasizing the differences of the RDU compare to other systems especially working for FP.
 

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1. It's not a differential. Get that right.

2. No matter how much power you put through the PTU to the RDU, the RDU has a valve that will bleed off any excess torque. It was discussed on these forums before but I just can't find the reference. Still searching.
 

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1. It's not a differential. Get that right.

2. No matter how much power you put through the PTU to the RDU, the RDU has a valve that will bleed off any excess torque. It was discussed on these forums before but I just can't find the reference. Still searching.

It is CLUTCHES. If anyone can explain how they would not just slip when you apply too much torque I would be willing to say the RDU is a weak point. However, it sounds like there is no way to break the RDU, you would just throw off vehicle dynamics and overheat the RDU which would cause it to stop engaging the clutches until it cools down.
 
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It is CLUTCHES. If anyone can explain how they would not just slip when you apply too much torque I would be willing to say the RDU is a weak point. However, it sounds like there is no way to break the RDU, you would just throw off vehicle dynamics and overheat the RDU which would cause it to stop engaging the clutches until it cools down.
With the computer controls in place it will simply disengage to protect itself.

That said, much of the mechanical technology built into the car is based on wet clutch tech we've had for a very LONG time

Ever seen a hydraulic automatic transmission? There is an entire industry built around the concept of wet clutches right there. Failure points are well known, as well as what it takes to fix them. The RS's magic is in the control of those clutches. Upgrades will come, I think this RDU will go much further than people think. The issue will be heat, and the calibrations that control how torque is applied. They are essentially new fields for the aftermarket. And until we understand and decode the RDU's computer controls there will be a ton of questions.

We'll get some traction on this if we give it time (pun intended).
 

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With the computer controls in place it will simply disengage to protect itself.

That said, much of the mechanical technology built into the car is based on wet clutch tech we've had for a very LONG time

Ever seen a hydraulic automatic transmission? There is an entire industry built around the concept of wet clutches right there. Failure points are well known, as well as what it takes to fix them. The RS's magic is in the control of those clutches. Upgrades will come, I think this RDU will go much further than people think. The issue will be heat, and the calibrations that control how torque is applied. They are essentially new fields for the aftermarket. And until we understand and decode the RDU's computer controls there will be a ton of questions.

We'll get some traction on this if we give it time (pun intended).
Fair enough. Good points.


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