What's the clamping force of the S4 and RS4 pressure plates? Seems to be conflicting info. SPEC too
 

Trying to find info for a B5 S4...

<a href="http://awe-tuning.com/pages/shared/part_detail.cfm?PMaI=1&PMoI=4&PEI=6&PP=s4_27t_driv etrain.cfm&PPT=Drivetrain&IL=s4stage2">AWE site</a> makes note of "OEM is 2600". I presume they mean OEM S4?

<a href="https://forums.audiworld.com/s4/msgs/740182.phtml">This post</a> by Tanner says:
"S4 is 1300PSI
RS4 is 1800PSI"

<a href="https://forums.audiworld.com/s4/msgs/1787547.phtml"> X-1 Racer says</a>:
"RS4 pressure plate = S4 pressure x 2"

<a href="https://forums.audiworld.com/s4/msgs/1463079.phtml">This post</a> by ToastyK04s refers to his SPEC Stg 3 clutch and says:
"Mine has a 6-puck disc with a pressure plate that has nearly twice the clamping force of the RS4 setup."

So, what's the clamping force on the SPEC Stage 3? What about the other stages of SPEC clutches?

found this info on SPEC after posting:
<a href="https://forums.audiworld.com/s4/msgs/1204658.phtml"> Jason Leone says</a> :
Stage 1:
Modded pressure plate (100psi over RS4)
Stage 2:
Modded pressure plate (375psi over RS4)
Stage 3:
Modded pressure plate (375psi over RS4)

This conflicts with ToastyK04's comment of Stg3 being about 2x that of RS4.

Just a little info I got the other day
 

the updated OEM clutch for the B5 S4 is the RS4 setup. The RS4 clutch should be around 2600-2800 psi.

who said that? that's very interesting :)

A friend of mine which builds my custom clutchs.
 

He said the old S4 pressure plate was about 2600 psi while the RS4 pressure plate he tested was 2800 psi. There is no way a stock S4 clutch could be 1300 psi since the stock A4 1.8t is 1450.

BTW Mike, I've heard the same - just the pivot bearing is different, and thus why they *feel*
 

different, yet both have the same clamping force. It is a mystery then as to why it seems the RS4 holds up better to power, if they have the same plate and disk.

interesting nonetheless

Are the disks exactly the same?
 

Some companies use different material on the disk just to make a clutch setup seem like it can hold more pressure or seem like it has more clamping pressure when it does not. Just a little trick that has been used and is still used by some these days.

i thought the discs were the same

same Luk P/N from what I recall

Yes it is the same part.