Jamie@dundonmotorsports

Until very recently you didn't have a great option for Motorsports Dampers for your Front Axle Lift equipped 991.2 GT3RS and 991.2 GT2RS.

Now you have a great option, made in the USA, with great USA based support, exclusively from Dundon Motorsports.

We partnered with Motion Control Suspension late last year to bring this idea to fruition. Keeping your street car streetable, still be able to lay down lightning laps and improve driving comfort. We brought Seth Thomas in as a test driver for his car early as it didn't have FAL so was easy to get him up and running quickly.

Seth and I had always discussed the "chattering" and instability the stock 991.2 GT3RS displayed on small pavement undulations, the lack of grip out of tight mountain road switchbacks and how the car was very unsettled going over the curbs at Road Atlanta. Couple these traits with the fact that many owners are having issues with leaking stock struts meant that it was high time to get these dampers out!

The results on the Dundon Lab Rat saw about 2-3 second improvements in this amateur drivers hands, mainly from how much easier it was to drive the car fast, improving confidence to go that much faster. Much better balance, a little breath off the throttle and the nose points, smooth over the curbs so much that you can take more aggressive lines that previously were very unsettling to the car. On the street the car is supple without being soft. A nice combination for an RS!

We have 3 other 991.2 GT3RS getting installed, one in Washington, one out of GoldCrest Motorsports, and another in Texas that frequents COTA. We'll use this thread to keep updates and answer questions. Seth will weigh in as well on his thoughts and notes on his trips around Road Atlanta!

You can find them as complete kit with PASM delete, springs pre selected as well as street and track settings established. And those with a DSC Box you can keep it, we can use it as a PASM delete by setting the shock outputs to zero!

https://www.dundonmotorsports.com/co...32106491215908

Combined with Emotion Engineering Tension Arms and Drop Links your Weissach cars are complete (and the carbon bars can finally be adjusted for preload when lowered).
Or with the Emotion Stage 4 for those without Weissach to get the rubber out of the suspension.

We are working on the Pneumatic Front Axle Lift Cars (991.1 GT3/RS- 991.2 GT3). As soon as it's available we'll let you know!

A little intro Video

Seth Thomas

I thought I would give my thoughts on the new suspension offered by MCS and Dundon Motorsports since I was the very fist beta tester of this setup on my car. The notes I have copied below are from my experience with my 991.2 GT3RS since the delivery day. These are what I gave to MCS and Dundon for feedback on the setup to try to make the best suspension out there for a 991 GT Porsche. These notes are long but they are unedited and were collected life of the ownership of the car.

When I first took delivery of my 991.1 in 2015 I loved the car but I new it needed a little bit extra to make it a great track car. My first impressions then were to add a set of MCS shocks with stiffer springs. My reason at the time was because the stock suspension was too soft for the performance of the car on a track. On the street it was the most capable but comfortable GT car Porsche had produced to date. Come 2018 when I took delivery of my 991.2 GT3RS I immediately felt the difference Porsche made in the car. They finally had the spring rates correct for this chassis, or as close to it as you could get with the street shocks and ride quality. I was in love. Then I took it to the track at Road Atlanta for a Driving Club at Road Atlanta track day. It was an amazing performing car on track but I knew again it could slightly be improved with the shocks. The car was great but the closer to the limit you get with it the more it gets a nervous feeling coming from the suspension. It doesn't lose grip but it does slide and move around on you especially as you heat cycle out your tires. This movement gets worse and the car starts to feel more unstable.

Now move to the street side of driving the new chassis. I love it in the soft mode on the street but it does ride stiffer and rougher than the 991.1. You can feel the bumps in the road move with the stiffer springs in the 991.2 which has been one of the most complained about issues with the 991.2. I knew the MCS shocks would help with this part of the car. Once installed the street drive of the car was instantly transformed to being very much like the 991.1 on the street but better. It now absorbed all the bumps of the road much like we would expect. It wasn't overly stiff when going on the interstate and as you can see from my notes made the car a much easier and comfortable car to drive on the street without compromising the performance characteristics of the car in the curves.

So my apologies for the long notes but to sum it up THE MCS/DUNDON SHOCK PACKAGE MADE MY 991.2 GT3RS EVEN MORE AMAZING ON THE STREET AND TRACK. Any questions on this please don't hesitate to reach out to me with questions on this setup. I would love to answer any without a sales pitch.


GT3RS initial thoughts on suspension



Quick outline format of the initial thoughts on the 2019 Porsche 991.2 GT3RS Suspension both stock and with the MCS/Dundon 3-way dampers.



1. First impression after driving my 2016 991.1 GT3RS to dealer to trade in on the new 2019 GT3RS was the new 991.2 had a much stiffer suspension under it. You could feel the slight chatter of the road better than the 991.1 3RS. Going over bridges and expansion joints on the highway, the .2 3RS had more bounce from the increased spring rates stock. The 991.1 was much more compliant of a street car than the .2.

a. Areas the .2 was different: any small bump car felt planted but jittery

b. Interestate driving the expansion joints were felt more. Makes it harder for my wife to nap in the car. LOL

c. Car feels more planted than the .1 when pushed to the limit.

d. Front and rear spring rates are definitely better matched

2. Stock feedback For track and spirited mountain driving

a. At Road Atlanta my initial impression of the .2 GT3RS was this is how the .1 should have been from Porsche. Front and rear spring rates are better matched for track driving.

b. Transition from left to right for the esses at Road Atlanta was much better. Body roll with sway bars in middle front and middle rear was much more manageable and quicker.

c. T1 was faster on entry with more grip but on exit you could feel the rear be nervous. Never loses grip but when the front and rear compress on exit with power application it feels like it could oversteer easily.

d. Curb in T3 was pretty good but the landing could be harsh causing the rear to step out slightly when the speed increased on exit.

e. Exiting T4 and entering the esses the car feels nervous. The bodyroll is controlled and feels good but the tires feel like they are skipping or chattering a bit over small surface bumps. Very high frequency type chatter. Entering the esses there is a surface change and a bump. You can really feel the bump which can make the car feel nervous going over it.

f. Exit curb in T5 was not usable with all 4 wheels at all.

g. T10A and T10B curbs where usable but the chassis feels nervous over them. You can feel the wheels and tires skipping across the gators.

h. Exiting T10B the chassis gets in a little bit of a bind situation the rear where it wants to skip across the track with too much throttle.

i. T11 going under the bridge the car has a nervous feel to it from both the front and the rear. You can feel the tires slightly being jittery with small surface bumps. This is very similar to exit of T3 and exit of T5

j. T12 is fast but the car is nervous. There are a couple of small surface bumps that make the car chassis chatter when driving over them. The car doesn’t lose grip but it creates a nervous feeling.

k. For Mountain Driving the car is really pretty good out of the box from Porsche. In the quick switchback sections of the road you can feel the chassis working together. On a very smooth section of road the car is good. On an older more traveled road with surface cracks and transitions from one degree of banking to another car lacks some. It gets nervous feeling. This can be a good thing on the street because it causes you to not push the car as fast but you can feel this limiting traction too.

l. Transitions over banking/camber changes in the road you can feel the suspension lag behind. Over these transitions the car will spin the rear tires slightly. Feels like the tires are not following the road and suspended in the air slightly.

m. Rear of the car when compressed going uphill with banking/camber in the turn you can feel it hop/bind up slightly under the compression. Feels similar to hitting a soft bumpstop. This causes a slight chatter of the rear.

3. 991.2 GT3 RS with MCS 3-Way Dampers

a. Soft Settings on Shocks

b. Initial street driving impressions were very positive. Interstate/highway cruising was much more composed.

c. Driving over bridge expansions the car stayed more on the pavement and had less stiff bounce to it than before. You can really feel the shock absorbing the and controlling the spring over these bumps in the road.

d. Front and rear working together feels very similar to stock. This I feel is partially because we didn’t change the stock springs.

e. Low Speed bumps (>50MPH) are still very similar to stock feel. A can pressure change or less compression can help with this but I feel this is more with spring rate than shock.

f. Driving over the mountain roads was much more enjoyable even in the soft setting.

g. Transitions on camber you could you feel the tires stay more planted with the road surface. Small undulations or surface bumps were absorbed and smoother on the tires.

h. Overall the car feels less nervous and twitchy over different road surfaces. Shocks control the suspension much smoother than stock setup even with same high spring rates in the car.

4. 991.2 GT3RS Track Driving impressions with MCS 3-way Dampers

a. Much easier car to drive on the track. Even with hot track surface temps and tires that are heat cycled out the car was just as fast as before. You could feel how the new shocks with more compression control really helped find grip and create confidence throughout the lap. Nervous feeling of the chassis is gone

b. The biggest change with the new suspension is the loss of the nervous chattering feeling of the chassis. Shocks and springs now feel like they are keeping the tire on the ground more and not skipping over any small bump or surface change.

c. Using the curb in T3 now feels more absorbed and not like the car is being shot up in the air going over it. The landing is absorbed and smooth with very little drama. Before the shocks you always had to use 3rd gear because anymore speed would cause the car to land hard and lose grip. Now it feels like the car is between 3rd and 4th gear speed wise. I think it could be taken in 4th gear with no problem which I feel would give slightly more speed. Definitely more grip. Slight tire rub on the top of the inside of the left rear wheel well.

d. Turn 4 the car definitely has more grip. You can feel the shocks working on the transition from turning right to left coming off T3. The chatter of the surface is gone. This allows more throttle going around T4. The transition into the esses is much smoother.

e. Esses are a big difference in confidence with the car. No longer do you feel the bump that was there at the first curb. It is absorbed both front and rear smoothly. Nervous feeling going over it is gone which allows a better for staying on the throttle keeping the rear planted through this section.

f. Turn 5 is very similar to T3 now. I feel like there is a lot more speed there which puts me between 3rd and 4th gear. I haven’t mastered that speed yet but the front of the car feels a lot more planted. The exit curb can be used with the right side of the car but I don’t think you can go 4 wheels over it.

g. T7 is a spot I was surprised how much better the car feels. On turn in the car finally responds really well. When you ask it to point it does so immediately. Before if you tried doing this turn in 3rd gear it would want to understeer a lot. After the shocks the understeer is reduced and feels very smooth. I still think 2nd gear might be faster than 3rd going down the straight but it feels like you could make up a lot of this by using 3rd gear on the entry.

h. T10A and T10B the car is rock solid over this section. The transition between left and right feels quicker and more absorbed with the shocks. Going over the curbs in both turns doesn’t feel as rough/nvervous with the chassis as before. Like T7 I feel there is more grip on turn in which should allow more speed through the first part of T10A. In T10B the chassis good. There is still a slight chassis hop like there is too much rebound in the rear but this could due to the progressive rate spring in the rear.

i. T11 there is no more chatter/nervous feeling in the car going over the crest of the hill. The bump at the top of the hill is much less pronounced and you can feel the wheels follow the road better. With TC still on it will cut power going over the crest as the tires slightly spin as they get light.

j. Turn 12 is so much better. Not saying there is more grip but the car feels more composed at the bottom of the hill. The nervous feeling of the chassis is gone. I feel there is a lot more confidence in going down the hill now than before.

SmokinGTS

I drove a 991.2 GT3RS yesterday at the track with this set up and feel Seth was spot on in his assessment. The car was so easy to drive it wasn't even fair. How do I go back to my old 991 GT3. May be time for a damper upgrade.

tqevo

Comparisons to MR 3-way coilovers?

Seth Thomas

To be fair and honest I do not know as I don't know many people in the US who have installed a MR KW 3-way on their car. What I do know with the Dundon MCS package is they are a true motorsport damper that is fitted on the street car. This is a no compromise setup as far as parts and ability fo the shock to control the chassis. Two positives with the MCS is they are made here in the US so the ability to get them rebuilt if needed is very easy which also makes customer support for the shock 1st class. The guys in the MCS office are very open to helping guys out with help on how to dial the shocks in when needed and they are located in the Eastern Time Zone so it works really well for when you are at a track and need help.

What I can tell you that I do know on the MCS shocks on my 991.2 GT3RS is compared to other KW setups I have driven the shocks absorb bumps much better and much more controlled than the KW. There is one very fast 991.2 Cup MR that I know who switched his setup from the KW to a MCS 4-way setup. His feedback and my feedback on the shocks were almost mirror images of each other when talking about the difference of the cars on track at Road Atlanta. I was shocked by this when you have a street car and a racecar comparing each other for feedback. Both us felt the MCS shocks calmed the car down on the track making it easier to drive the car at the limit than with the stock shocks from either car (KW or Porsche Stock).

Since I did some of the development of this kit please ask away with any questions or reach out to me if you would like more info. I will answer you without a sales pitch and with honesty in relation to your goals with your car.

GrantG

My impression is that the KW stuff with integral (or piggyback on 4-way) cannisters is more of a Clubsport product and the MCS, Ohlins, and a couple others with totally outboard cannisters are at a higher (true racing) level. Happy to be corrected if I'm wrong...

M3the01

Really good stuff here, definitely on my list for the gt2rs. The package comes with springs? I'm always amazed suspension is so cheap compared to everything else on these cars. With FAL, is the lift the same? As per the adjustability, need to hit the top of each damper and the piggy backs? How easy to adjust for track versus street? The rear would be pita. The gt2rs I gotta leave on soft for the street as it is unsettled so easy, especially with moderate power. Even on the track, depending on which, I will leave on soft.

Seth Thomas

Yes

Yes the factory lift system on the GT2RS is retained and will operate as it does from the factory. This is the only suspension system I have seen that retains the factory lift.

I am not sure what you are asking.

Yes the rear can be a PITA but there are extensions for the rebound adjuster on the top of the shocks that can be reached with your arm reaching behind the seat. I have these on my car and I am awaiting a 311RS rollbar to be installed to fully test out the adjusters with a rollbar in the car.

Street vs. track settings. There are optimal track settings but the car performs fairly well on track even with the street settings on the shocks. With the "soft" settings on the shocks and while driving on the track, the car feels better than stock but does not lose grip. Change to the track settings, you will find the car is more confident to drive with less body roll with the rear and the front working really well together. Drive the car on the street with the track settings still in there is feels like the difference of the Sport PASM button pressed but it absorbs the bumps of the road so much better. This is one of the characteristics of the MCS shocks that makes them so much better than what Porsche delivers these cars with. They absorb the initial hit of any bump that makes the stock 991.2 GT cars feel so stiff without giving up an performance. They blowoff the pressure and control it like a true damper should. I have been driving my car with the stiff track settings on the street lately to get a good feel of how it will behave and I am really impressed with the quality of the ride. Yes it can be stiff on really bumpy roads in this track setting but on a typical interstate or back road they ride and keep the car planted.

For rear traction on the GT2RS on the street I feel these will make a big difference. I don't have experience yet driving a GT2RS with the Dundon MCS shocks installed yet but I do have a good feel for how the shocks in the street setting help to gain traction over the stock shocks. In the mountain roads of North Georgia my car stays planted compared to when it was stock and compared to my friends stock GT3RS.

Let me know if this answers your questions and if you have anymore ask away.

ngng

was anything changed with the shocks on the dundon kit, or is this just a mcs kit?

Jamie@dundonmotorsports

Package comes with springs, PASM Delete and everything to get the car setup! We'd recommend that for the Weissach cars you also do adjustable sway bar end links and Tension rods to get the most out of the alignments.

The adjustments are Compression on the canisters and rebound on the tops of the shock bodies. The Rear has a flexible extension that makes it easier to reach.

Jamie@dundonmotorsports

We worked together to co developed the MCS dampers to work with factory lift, bring Seth in to test it, and leverage the best of each company to make the GT cars faster.

Nizer

Do the GT3 RS and GT2 RS packages use the same spring rates and valving?

M3the01

I worry about touching those carbon sway bars... Porsche looking to deny anything on warranty claims. Thoughts?

A/S

On the stock suspension, both cars use the same springs and shocks. The calibration of the PASM could (and should) be different, but this is a moot point on fully adjustable manual shocks.

Actually, there is a big problem with WP cars. Once you adjust the ride heights, the sway bars are pre-loaded, and you can't remove the pre-load as the drop links are static. At the beginning of my .2 GT3RS WP ownership, it was very difficult to adjust the sway bars once I got the car's ride height adjusted and corner weighed. I installed adjustable drop links, and problem solved.

Preload is the main reason for bending and broken drop links in these cars, and a Carbon Fiber drop link won't bend. Drop links break during heavy load and at unexpected times, if you track you car, the consequences of a sudden broken front drop link can be catastrophic.

MCS (Motion Control Suspension)'s gurus include Lex Carson. He did some work for me many years ago on 3 different cars I had with Moton Motorsports shocks. Lex was the the guy running the Moton Sales and Operations for USA. Moton as a company was started by ex-JRZ people with the intend to build a better shock, and IMHO they did. MCS was started as a company to build a better product than anything out there (Penske, Ohlins, KW, etc.).

The KW units in the MR packages are much better than the stock suspension, but side by side to the MCS package co-developed with Dundon and Seth, there is no comparison. The MCS package is superior in construction, design and capabilities, there are true Motorsports units.

Without doubt, the MCS package is the best bang for the buck after proper tires (which require matching wheels). With all the tuning I have done on the DSC, the high-speed compression is one of two things I cannot dial out due to physical limitations on the stock shocks, the other one being how quickly the shock bodies control the body when initially loaded (low speed rebound). I found improvements in lap times with the DSC Sport controller using the DSC tunes, and even more time using my tunes, but there are limitations that only true race shocks can provide.

In the next few months the feedback from this MCS kit will start to show up with lap times differences to the stock cars, pretty amazing that this platform is being developed even more, and with Dundon's excellent customer service, I have no doubt that information on settings for compression, rebound, high-speed rebound for this kit will be available. E-Motion is also involved with Dundon, so setup and progress is not promising, it is guaranteed.

Awesome...

Jamie@dundonmotorsports

The spring packages are tailored to the customer, within a range. Hard core time attack GT2RS with our aero package and sticker hoosiers will setup a bit different than a GT3 Touring for example. The nice thing is the MCS 3ways have a very wide range of adjustment so we can dial them in within the spring ranges without a valving change.

You're actually better off changing to an adjustable end link than the non-adjustable end links that factory Weissach comes with. Being able to dial out the preload on the bar will make a carbon bar last longer as it's not always in tension...