991.x GT3 RS best mods for track
#46
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Front 2-piece AP J Hook Discs in PCCB size= https://www.essexparts.com/essex-des...1gt3PCCB-front
Rear 2-piece AP J Hook Discs in PCCB size= https://www.essexparts.com/essex-des...pccb-rear39032
Front Ferodo DS3.12 pads= https://www.essexparts.com/ferodo-fc...312-brake-pads
Rear Ferodo DS3.12 pads= https://www.essexparts.com/ferodo-fc...312-brake-pads
__________________
'09 Carrera 2S, '08 Boxster LE (orange), '91 Acura NSX, Tesla Model 3 Performance, Fiesta ST
Jeff Ritter
Mgr. High Performance Division, Essex Parts Services
Essex Designed AP Racing Radi-CAL Competition Brake Kits & 2-piece J Hook Discs
Ferodo Racing Brake Pads
Spiegler Stainless Steel Brake Lines
704-824-6030
jeff.ritter@essexparts.com
![](https://rennlist.com/forums/signaturepics/sigpic110137_8.gif)
'09 Carrera 2S, '08 Boxster LE (orange), '91 Acura NSX, Tesla Model 3 Performance, Fiesta ST
Jeff Ritter
Mgr. High Performance Division, Essex Parts Services
Essex Designed AP Racing Radi-CAL Competition Brake Kits & 2-piece J Hook Discs
Ferodo Racing Brake Pads
Spiegler Stainless Steel Brake Lines
704-824-6030
jeff.ritter@essexparts.com
![](https://rennlist.com/forums/signaturepics/sigpic110137_8.gif)
The following users liked this post:
Nein11RS (11-10-2023)
The following users liked this post:
JRitt@essex (11-10-2023)
#48
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
@JRitt@essex this may be the better way to go for me for sure. Thanks for the info!
#50
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Any tips for popping out the rear inner pads while on jack stands?
The fronts are super easy to grab with channelocks(and turning the wheel) on the pad backing plate but i find the rears pretty tricky without actually getting the car on a lift.
The fronts are super easy to grab with channelocks(and turning the wheel) on the pad backing plate but i find the rears pretty tricky without actually getting the car on a lift.
Brake squeal is primarily a function of two things...1) pad compound choice and 2) if the pads/discs are bedded-in or not. One of the great things about our system, and Ferodo pads in particular, is that you can run a milder pad like Ferodo DS2500 on the street and an aggressive race pad on the track like the DS3.12. Since our calipers make it so easy to change pads, making that swap is a piece of cake. That said, nobody enjoys changing pads, and many of our customers just leave the DS3.12 in the calipers all the time. The downside to running DS3.12 on the street is that the cold bite isn't quite as great as the DS2500, and when you run the DS3.12 cold they'll wear your discs faster than a milder pad (which is true of any racing pad). Here's an article that closely examines the three primary Ferodo pad compounds: Which Ferodo Racing Pad Compound is Right for Me?
Regarding the pads and disc contact...As you're driving the suspension is constantly compressing, the disc is moving around laterally, and the pads are being pushed slightly away from the disc. Think of the seals in the caliper as a spring or hinge attached to the side of the piston, rather than just a ring through which the piston slides. In an AP Racing competition caliper, the groove in which the seal resides isn't a square cut groove.It has angles. When the pistons slide in or out there is friction between the outer piston wall and the seal, and the seal distorts a bit as shown in the illustration below. A caliper piston sliding out to the left would distort the seal in this manner (the slashes are the seals on either side of the piston):/
---
---
\
As the piston slides back in to the right, the seal does this:
\
---
---
/
There is a certain amount of tension or friction that needs to be overcome before the piston actually starts moving through the seal ring. That tension/friction keeps the piston from dragging on the disc once the pistons are pushed back into the bores by the disc/suspension movement.
Thanks again for your continued support gents!
Regarding the pads and disc contact...As you're driving the suspension is constantly compressing, the disc is moving around laterally, and the pads are being pushed slightly away from the disc. Think of the seals in the caliper as a spring or hinge attached to the side of the piston, rather than just a ring through which the piston slides. In an AP Racing competition caliper, the groove in which the seal resides isn't a square cut groove.It has angles. When the pistons slide in or out there is friction between the outer piston wall and the seal, and the seal distorts a bit as shown in the illustration below. A caliper piston sliding out to the left would distort the seal in this manner (the slashes are the seals on either side of the piston):/
---
---
\
As the piston slides back in to the right, the seal does this:
\
---
---
/
There is a certain amount of tension or friction that needs to be overcome before the piston actually starts moving through the seal ring. That tension/friction keeps the piston from dragging on the disc once the pistons are pushed back into the bores by the disc/suspension movement.
Thanks again for your continued support gents!
#51
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
![](https://cimg5.ibsrv.net/gimg/rennlist.com-vbulletin/1080x1350/green_gt3rs_with_apracing_discs_663003402dd944639dfdd0e604fc9375ad141516.jpg)
![](https://cimg0.ibsrv.net/gimg/rennlist.com-vbulletin/1440x1079/274726441_10217549043556375_6058386821195207156_n_79e9dee0dfeb614fb5c324d6ad7b683415ca7d13.jpg)
![](https://cimg0.ibsrv.net/gimg/rennlist.com-vbulletin/2000x1504/img_0055_be029b0e6fae8d89abc5edfe4dd35e5e6cb83ac5.jpg)
#52
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
All the players in the brake game have this conversion available. GiroDisc, PFC, etc. Go with whatever is priced best or tickles your fancy, the PCCB to iron conversion has been a common option going back to 996/997 days. Not exactly rocket science.
The following users liked this post:
Nein11RS (11-13-2023)
#53
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
There are layers of ride height, alignment, and sway bar adjustments to work with before deciding the stock suspension components won't do.
...
Would also suggest you're not guaranteed better performance with aftermarket dampers. This isn't like swapping stock AMG or M suspension for KW, Ohlins, etc. RS dampers are legit. You'd have to work on it (tune), and know what you're doing with 2 or 3 way adjustments to match or exceed stock damper performance on a given track.
...
Would also suggest you're not guaranteed better performance with aftermarket dampers. This isn't like swapping stock AMG or M suspension for KW, Ohlins, etc. RS dampers are legit. You'd have to work on it (tune), and know what you're doing with 2 or 3 way adjustments to match or exceed stock damper performance on a given track.
#54
#55
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Good point - most of these aftermarket solutions are traditional, non-electronic shocks. I'd argue that PASM is an inherently more versatile technology, meaning easier to set up and able to perform well in a wide variety of scenarios as they can react based on steering angle, G-forces, vehicle speed, etc. In addition, GT car shocks are quite good quality, it's not like they are junk because Porsche was trying to build a cheap car! Thus I wouldn't expect an aftermarket traditional shock to be better in every way. Instead, they can be tuned (if you know what you are doing) to optimize for a particular scenario. This is certainly what race teams are looking for, but may not be what many DE participants want to sign up for.
Run 3 way coilovers on another car, never once occurred to me that I should do the same on RS.
One of the primary advantages of aftermarket dampers on most platforms is the gain of height adjustability, a drop of 2" + new aggressive alignment specs feels like night & day on an M or AMG. Years ago I put coilovers on an M car and gained like 3 seconds on a 2 minute lap in session 1.
GT3/RS already have all of that built in. So, what's left is the combination of assumed superior aftermarket damper tech and your own track specific damper tuning ability. You're betting that combination will be better than what the GT damper department did, with feedback from Bergmeister and Estre running sub 7 minute laps daily.
And so, I run stock suspension on the GT3/RS. The cars' limitation is tires 99/100x, you're hitting that limit long before being let down by the dampers.
#56
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Good point - most of these aftermarket solutions are traditional, non-electronic shocks. I'd argue that PASM is an inherently more versatile technology, meaning easier to set up and able to perform well in a wide variety of scenarios as they can react based on steering angle, G-forces, vehicle speed, etc. In addition, GT car shocks are quite good quality, it's not like they are junk because Porsche was trying to build a cheap car! Thus I wouldn't expect an aftermarket traditional shock to be better in every way. Instead, they can be tuned (if you know what you are doing) to optimize for a particular scenario. This is certainly what race teams are looking for, but may not be what many DE participants want to sign up for.
Yes the PASM eletronically adjustable shocks can work and be more efficient in tuning by theory but it is not user friendly and there are very few companies who make it easier for you the end user to make the adjustments. As for the quality of the stock shocks, they are not quality. They have technology in them but they are actually cheaply made. My 991.2 GT3 RS shocks were weeping from the seals of the shock with less than 1500 miles on them. You can see a coating of shock fluid on the bodies of the shocks. This was with street driving only. I was not very impressed with their quality especially for the cost of the replacement shock from Porsche. At $2k per shock for replacement I would rather spend that money on a quality aftermarket shock. My MCS shocks are 4 years old now with no issues in the seals leaking, weeping, or anything else. Everyone who drives my car has said it is one of the better handling 991.2 GT3RS they have driven.
#57
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Yes the PASM eletronically adjustable shocks can work and be more efficient in tuning by theory but it is not user friendly and there are very few companies who make it easier for you the end user to make the adjustments. As for the quality of the stock shocks, they are not quality. They have technology in them but they are actually cheaply made. My 991.2 GT3 RS shocks were weeping from the seals of the shock with less than 1500 miles on them. You can see a coating of shock fluid on the bodies of the shocks. This was with street driving only. I was not very impressed with their quality especially for the cost of the replacement shock from Porsche. At $2k per shock for replacement I would rather spend that money on a quality aftermarket shock. My MCS shocks are 4 years old now with no issues in the seals leaking, weeping, or anything else. Everyone who drives my car has said it is one of the better handling 991.2 GT3RS they have driven.
But if you do have a bum shock, at a replacement cost of $2k per, I do agree it's worth considering aftermarket replacement and potential improvement.
#58
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Respectfully, counterpoint to them being low quality. Few dampers can take the beating I've put on my stock 991.2 GT suspensions without issues, the need for rebuild after thousands of track miles at a minimum. Dozens of heavily tracked GT cars down here, nearly all with stock, original suspension components performing excellently.
But if you do have a bum shock, at a replacement cost of $2k per, I do agree it's worth considering aftermarket replacement and potential improvement.
But if you do have a bum shock, at a replacement cost of $2k per, I do agree it's worth considering aftermarket replacement and potential improvement.
#59
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Wasn't arguing that no top tier aftermarket dampers, with optimized track specific setup, could exceed performance of stock. Are most GT3/RS guys on Cup 2 or SMR2 going to exploit that performance advantage vs. an optimized stock setup? Very doubtful, but spend away. Cheers.
#60
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I just started tracking a 991.2 GT3 RS so right there with you getting up to speed with these cars. I can tell you that a proper alignment made a world of difference. My first time out was on the stock settings with Hoosier R7s. The next time out went with a much more track oriented alignment and made a huge difference. Ran -3.2 with a bit of toe out at the front and -2.6 with a bit of toe in at the rear and it was like a whole different car. I was also on Pirelli slicks last time which definitely helped too. The car actually wanted to turn in now. We swapped the top mounts to get that camber and keep the caster happy but since have swapped in the full compliment of E-Motion arms as I prefer to get the desired alignment in that manner and have the option to knock the camber back down below -3 in the front on the street. Would recommend a better alignment to start for sure after seeing how well my car responded to the change. Depending on what wheels you are running there are some quicker tires out there as well. Not the biggest fan of Hoosiers but they will be quicker than the 2Rs or Trofeos. Good fitments out there in 19s for a good track setup. Forgeline makes a popular setup. I prefer Signature Wheel as they make an excellent track wheel (been beating the crap out of their wheels racing the last few years). Also swapped out the brakes - full AP Racing kits from Essex.
If you get into replacing the suspension there will be another option soon. Have a test kit on the way from Nitron - their elec-TRON version of their R3 kit on the way that we will test extensively until we have it dialed in exactly like we want it. They already have a traditional 3way kit available but the addition of the electronic component ought to step it up a notch but we will see how that goes once we have it. Very excited to get my hands on these and will do a lot of before/after comparisons with them. Also just added a Verus Engineering full aero kit and looking forward to running it out at COTA next week. When we have the suspension nothing else will change though until we finish getting it dialed in.
Really though a proper alignment was a big first step.
If you get into replacing the suspension there will be another option soon. Have a test kit on the way from Nitron - their elec-TRON version of their R3 kit on the way that we will test extensively until we have it dialed in exactly like we want it. They already have a traditional 3way kit available but the addition of the electronic component ought to step it up a notch but we will see how that goes once we have it. Very excited to get my hands on these and will do a lot of before/after comparisons with them. Also just added a Verus Engineering full aero kit and looking forward to running it out at COTA next week. When we have the suspension nothing else will change though until we finish getting it dialed in.
Really though a proper alignment was a big first step.
Thanks