M-3200-R rack/steering feel

Napoleon85

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I am not aware of the stock ratio.

This conversation came up in my STX build thread after the "shuffle" game was played with a 3450lb car + 270lb driver on a course that would make a 60 second course on a postage stamp. From what little research I found the default rack is 15.642:1 which would make it the same as the FR500 rack.

Doesn't it vary based on the size of the wheel that was originally equipped? If you go out to FordParts.com there are many different part numbers referencing build dates and original wheel/tire size.
 

Sky Render

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Doesn't it vary based on the size of the wheel that was originally equipped? If you go out to FordParts.com there are many different part numbers referencing build dates and original wheel/tire size.

No. Go read the ENTIRE thread on the EPAS issue.

The different racks are for different calibrations based on the size of the wheels. The steering ratio is the same.
 

Whiskey11

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No. Go read the ENTIRE thread on the EPAS issue.

The different racks are for different calibrations based on the size of the wheels. The steering ratio is the same.

I think he was asking about the 05-10 Hydraulic racks... I don't know the answer to his question but I assume that it has to do with steering limiters but I wouldn't think there is that much need to reduce the lock to lock travel any with the ice skates they put on these cars for tires.
 

Napoleon85

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No. Go read the ENTIRE thread on the EPAS issue.

The different racks are for different calibrations based on the size of the wheels. The steering ratio is the same.

I assume you mean this thread

I am very familiar with the thread and issue - and below I have quoted what I based my assumption on. If we have three gears with different diameters, what do they affect besides steering ratio? Perhaps I've made some incorrect assumptions - but I would have thought a gear inside the unit with more or less travel would either increase or decrease the steering ratio.

I am far from an expert in this EPAS system though, so if I am wrong please show me where I can find information to correct my line of thinking.





seems they have a different unit for each wheel combination thecar can have. Maybe thats your problem. jsut throwing it out there


Description Year MSRP Price Core Price Your Price
Steering gear, mustang, 17" wheels, to 5/13/10 - power - electric - POWER - ELECTRIC
2011 $761.72 $400.00 $628.42

Steering gear, mustang, 17" wheels, from 5/13/10 to 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,104.57 $400.00 $911.27

Steering gear, mustang, 17" wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 18" wheels, from 8/16/10 - power - e - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 18" wheels, from 8/16/10 - power - e - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 18" wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front and rear wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front and rear wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16 - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

Steering gear, mustang, 19" front/20" rear wheels, from 8/16/10 - power - electric - POWER - ELECTRIC
2011 $1,070.67 $400.00 $883.30

It mentions the systems method of activation when you start the car and the fail safe if it loses the signal. Question is what will it do if you start it without the signal.


DESCRIPTION AND OPERATION
Steering System
Electronic Power Assist Steering (EPAS) System
The Electronic Power Assist Steering (EPAS) system consists of the following components:
• Power Steering Control Module (PSCM) — The PSCM controls the functions of the EPAS system and communicates with other modules that are on
the High Speed Controller Area Network (HS-CAN) bus. The PSCM is attached to the EPAS gear assembly and is not available separately for service.
• Motor — The EPAS gear uses a 12-volt reversible motor to control the steering effort. The motor is connected to the steering rack by a toothed belt
and a pulley/bearing assembly. The motor is used by the PSCM to move the rack inside the gear housing. Motor position is used to determine steering
wheel angle/position instead of using a separate sensor. The motor is attached to the RH side of the EPAS gear assembly and is not available separately
for service.
• EPAS gear assembly — The vehicle has three EPAS steering gear options available: 75mm travel, 68mm travel and a 63mm travel option. The steering
gear installed to the vehicle is dependant on the wheel and tire configuration the vehicle was built with.

• Steering shaft torque sensor — The steering shaft torque sensor is used by the PSCM to determine how much force is being used to turn the steering
wheel. The sensor sends out 2 signals, one for left and one for right. When the steering wheel is turned to the left, the left signal increases while the
right signal decreases, likewise when the steering wheel is turned to the right, the right signal increases while the left signal decreases. This allows the
PSCM to determine if the driver intends to go left or right in order to spin the motor in the appropriate direction. The sensor is mounted inside the
EPAS gear assembly and is not available separately for service.
• Inner tie rod — One inner tie rod is located at each end of the EPAS gear assembly and is available separately for service. There are three different
inner tie rods available, each matched to one of the steering gear options available for the vehicle. Care must be taken to make sure the correct tie rod
for the steering gear installed to the vehicle, is used when replacing an inner tie rod. For additional information, refer to Section 211-02.
• Outer tie rod — One outer tie rod is located at each end of the EPAS gear assembly and is available separately for service. For additional information,
refer to Section 211-02.
• EPAS gear bellows boot — One bellows boot is located on each side of the EPAS gear assembly. Each boot is held in place with 2 boot clamps. The
boots and clamps are available for service, refer to Section 211-02.
• EPAS gear isolator — One rubber isolator is located on the right rear attaching point of the EPAS gear assembly. The isolator aids in the reduction of
NVH concerns and is not available separately for service.
The EPAS system utilizes a rack-and-pinion type steering gear. Power assist is provided by a motor that is connected to the steering rack by a belt and a
pulley and bearing assembly. The steering gear and motor/module are serviced as an assembly. A new steering gear includes inner tie rods, however, the
inner and outer tie rods can also be serviced separately. For additional information on tie rod end service, refer to Section 211-02.
211-00-2 Steering System — Electronic Power Assist Steering (EPAS) 211-00-2
2011 Mustang,






Electronic Power Assist Steering (EPAS) System
The Electronic Power Assist Steering (EPAS) system provides power steering assist to the driver by replacing the conventional hydraulic valve system with
an electric motor coupled to the steering rack by a toothed belt. The motor is controlled by the Power Steering Control Module (PSCM) that senses steering
effort/use through an internally mounted steering shaft torque sensor. Steering assist is provided in proportion to the steering input effort and vehicle speed.
The EPAS system requires a 12-volt, hot at all times feed for system operation. The PSCM is activated when power is applied to the hard-wired ignition/run
input. After activation, the PSCM monitors the High Speed Controller Area Network (HS-CAN) bus to determine if the vehicle is operating in a manner
capable of supporting the EPAS system.
Once this is determined, vehicle speed sent by the PCM over the HS-CAN bus, steering shaft speed and direction sent by the steering shaft torque sensor and
steering wheel angle/position determined by the motor position all provide the necessary information for the PSCM to determine the amount or level of
assist provided by the EPAS system.
Assist is primarily based off of vehicle speed. As vehicle speed increases, the amount of assist provided by the system is decreased to improve and enhance
road feel at the steering wheel. As vehicle speed decreases, the amount of assist provided by the system is increased to ease vehicle maneuvering. If the
vehicle speed is missing or out of range, the PSCM defaults to a safe level of assist for all driving conditions. If the vehicle speed returns to the correct inrange
values, the PSCM adjusts the level of assist accordingly. Steering wheel/shaft speed, torque and direction information allows the PSCM to determine
how much assist is needed to turn the wheels right and left.
The PSCM continually monitors and adjusts steering efforts based on the torque sensor inputs to enhance the feel of the steering. Compensation is made to
reduce the effect of pull or drift that may be experienced when driving on roads with a high degree of camber. Active nibble control is also employed by the
PSCM to reduce the vibrating movement felt at the steering wheel that can be caused by driving on rough surfaces or out of balance wheels.
The PSCM is self-monitoring and has the capability of setting and storing DTCs. Depending on the DTC set, the control module enters into a "safe mode" of
manual steering. In addition, the PSCM may send a request to the Instrument Panel Cluster (IPC) module over the HS-CAN bus to display a message in the
message center to alert the driver of a potential EPAS concern.
 
Last edited:

Sky Render

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I assume you mean this thread

I am very familiar with the thread and issue - and below I have quoted what I based my assumption on. If we have three gears with different diameters, what do they affect besides steering ratio? Perhaps I've made some incorrect assumptions - but I would have thought a gear inside the unit with more or less travel would either increase or decrease the steering ratio.

I am far from an expert in this EPAS system though, so if I am wrong please show me where I can find information to correct my line of thinking.

The units are sealed. Ford refuses to even recalibrate them. I doubt you can just swap the gears, since that would also require a software change.

Sent from my toilet using Tapatalk
 
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Napoleon85

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The units are sealed. Ford refuses to even recalibrate them. I doubt you can just swap the gears, since that would also require a software change.

Sent from my toilet using Tapatalk

I doubt you can as well ... I just don't fully understand why they are different. If it's to shorten the travel of the steering that makes little sense to me since there is room for days with even the stock 19s ... :headscratch:
 

Mach2burnout

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I think he was asking about the 05-10 Hydraulic racks... I don't know the answer to his question but I assume that it has to do with steering limiters but I wouldn't think there is that much need to reduce the lock to lock travel any with the ice skates they put on these cars for tires.

Yes I was talking about the 05-10 Hyd. Rack. That is why I got interested in this thread because that's what the OP was discussing.
Yes the tires do leave a lot to be desired on these cars, But that's a different story when you put R comps on. And frankly I would love to have less lock to lock travel.
But to clarify I was strictly trying to gather some info about the rack ratios. Thanks for your answers.


Sent from iPhone
 

Department Of Boost

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I would like a faster steering rack too (2005-2010).

I do have limiters so my tires don’t rub my brake ducts. -20mm on each side. I don’t think I have touched them yet.
 

Mach2burnout

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I would like a faster steering rack too (2005-2010).

I do have limiters so my tires don’t rub my brake ducts. -20mm on each side. I don’t think I have touched them yet.

I'm really looking hard at a quickener. There fairly cheap, fairly easy to hook up and very reliable. The only reason I'm undecided is I don't want to end up with a steering so quick that its not drivable on the street. Of course there is those pesky rules. Lol some classes alloy them though.


Sent from iPhone
 

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