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Spring 2016 Shot by a bimmer buddy of mine outside Soldier Fields Lot 5
After hibernation was over I could get to the suspension mods I had been planning since later last year.
All parts had been sourced and were ready to go on before my first track day at Road America.
Here's the list:
A fellow Rennlister and I installed the front half in a day. With a few more hours we could have done the rear but I had my race shop finish the rear before they did the alignment. It was a good learning experience as we went full R&R with the front end including the brakes, uprights, LCAs, thrust arms, etc removed.
With the new setup and street/track alignment I was rid of the front end push and tonka truck look. The Eibach springs feel excellent and the progressive spring rate allows compliant street driving and firmer track driving. You can still definitely feel the rubber suspended suspension and the pre-load required though. While I would like it even tighter, I could be damaging parts driving on Chicago pothole filled roads with a hard suspension.
After this, the car then went in for its annual detail before I started to build the new roof rack to carry my track wheels. More on that to follow.
I was waiting to see some suspension mods from you, and glad you did it because I'm also thinking to do something with my GTS Sport Suspension as well (just because has 5 years, that's all)...but I'm quite confused which way I should take to not compromise the street comfort. I'm considering a whole plug-and-play kit (bolt-on) from Ohlins, or Moton or Bilstein. Did you evaluated that route before?
I was waiting to see some suspension mods from you, and glad you did it because I'm also thinking to do something with my GTS Sport Suspension as well (just because has 5 years, that's all)...but I'm quite confused which way I should take to not compromise the street comfort. I'm considering a whole plug-and-play kit (bolt-on) from Ohlins, or Moton or Bilstein. Did you evaluated that route before?
If you have the money go Bilstein Damptronic for sure. I will eventually. It allows you to corner balance the car and set your own ride height. A lot of guys go with inner mono ***** on the LCAs but IMO you need to go with solid pucks first and a monoball thrust arm before monoball on the inner LCA. The car is on marbles when braking hard from 100+ mph with rubber pucks on the LCAs. I bought them after my first track day this season and they were installed today actually. Street comfort is excellent on the car right now.
My next purchase will be the TPC DSC unit and that will bring the car back to street dampening specs that were better than OEM and improve balance and weight shift on the track too.
Wow, impressed with all the work you tackled. Just got my 2012 GTS with aero cup last fall. I'll have to look into the cover to accommodate the wing/spoiler. It is Basalt Black. My daily drive is an Infiniti Q60 IPL in Malbec Black--so both tough to keep clean. Is that cover for the 991 GT3?
Last edited by GTSMark; 05-18-2016 at 05:23 PM.
Reason: Added question.
Wow, impressed with all the work you tackled. Just got my 2012 GTS with aero cup last fall. I'll have to look into the cover to accommodate the wing/spoiler. It is Basalt Black. My daily drive is an Infiniti Q60 IPL in Malbec Black--so both tough to keep clean. Is that cover for the 991 GT3?
Thanks and congrats on a great 997! You'll love it as I do I'm sure.
The cover is from the 997.2 GT3. Here is the part number: 99704400012
It fits my Aerokit car perfectly. It's TIGHT the first time on but loosens up just enough after a bit of time (give it a couple weeks).
You'd think the 997.1 GT3 cover would be the one to get since it has the same wing but my dealer insisted on this one and it fits perfectly as you can see.
Yes, sa
w the correct part number for this on the Suncoast website. However, not sure I need to be taking advice from a Packer fan(sadly, I'm a Detroit Lions fan). Also, Michigan Wolverine. Nice to see the Badgers back in The Big House this year.
Last edited by GTSMark; 05-19-2016 at 10:12 PM.
Reason: add Picture.
Road America Track Day In the garage with my pals (2012 C6 Grand Sport & 2014 981 Boxster S)
Road America is not open too often for club or group tracks days. BMW, Corvette, Honda and Mazda groups have their turns but last year including PCA the most available for the 911 was four. LAPS Inc hosted one later in the year I had to miss but this year Shawn put it nice and early and I was able to stretch the legs on my new suspension mods on a proper high speed track.
A pair of other GTSs with an identical setup but on slicks (i'm running Nitto NT01 R compound) were turning 2:34. My second last lap of the day before my brakes boiled was 2:37 with plenty of room to improve and I lost about a second on that lap waiting for a point-by. Too many Cayman Ss on slicks not wanting to move over. I'm still figuring out how to overlay the GoPro video with Harry's Lap Timer... not as easy as it seems... but I'll post it here once I figure that out. I figure at current spec on NT01 I should be in the mid to high 2:20s with better braking.
Some things I learned:
1) High speed, hard braking with rubber front LCA pucks is actually pretty scary. Not sure how I didn't see this last year but the front end is on marbles braking hard into turns 3, 8 and especially at the infamous turn 5. Coming in hot at 135mph was like driving a knuckle ball. Setting up the turn was very difficult not knowing where the car was going to be on the track when the turn in point came. So, solid pucks were already on my list before my second session.
2) Brake cooling. Even with fresh(ish) Motul RBF 600 I boiled my brakes on the last session to MUCH drama.. more on that later. In fact, my brake sensor tripped on the last lap of my first session even with a pre-day tech pass of 50%+ brake pad thickness on the original OEM Textars. I had 90 minutes until my second session and thankfully had tossed a full set of Hawks Ceramics into my bag before I left Chicago. I figured no matter what was left on the current pads I was going to change them all anyway after pulling the first wheel to inspect. Wheels off to wheels on I changed all four corners for the very first time in 39 minutes with a jack and hand tools. I felt pretty good about that, even with the Corvette IMSA team practicing the same thing in 3 minutes flat in the garage spot next to us.
There was no drama the rest of the day until a brown stain moment on the very last lap of the fourth of five sessions. I still don't know why but I decided to double tap the brakes and set the pads before every braking zone during the last two laps of the day. Our cars set the pads automatically when the DME senses abrupt throttle lift. So I still dont know why I decided to do this. Either way, no drama until I passed the flag stand at 125mph down the front straight. Double tap..... no pressure. WTF?!?! TIME TO POOP! I immediately eased off the throttle, tested again with little pressure and with Turn 1 coming up I threw out the anchor. There was enough pressure to make the turn using all of the curb and get the car down to 3rd. I put on my flashers and moved off line to limp to the turn 5 track exit. Thankfully there was a full course black flag at the same time (i thought it was for me at first) when the day's cliche track day douchebag stuffed his GTI into a wall after the Kink (physically he was fine).
My brakes came back by turn 5 and I decided to call it a day.
After consulting my notes from some other GTS track guys and my racing shop who happened to be track side that day providing support, I need better cooling (no sh*t). GT2 ducts and Pagid Yellows (duh) were advised. I already planned on upgrading to Pagids next month and the 350mm Turbo brakes all around next year but will accelerate the TT brake package now (anybody selling?). The braking on these cars is phenomenal but better cooling and pads will help even more especially on brake intensive tracks like Road America where I would like to go nine-tenths.
More to come as I sourced Rennline engine mounts and solid pucks from fellow RL members and another track day at a shorter track (Gingerman) next week.
Cheers!
If it aint broke, fix it anyway In the rain at the June Supercar Saturday show.
I really wanted to entitle this post 'Puck It' but I found more to 'fix' than just the front LCA pucks.
If you read the previous post on the suspension mods you'd see that the front LCAs were standard GT3 LCAs with no modification. Well, those center eccentric pucks that attach to the thrust arm have rubber bushings and under hard braking from over 100mph the front end is like a giraffe on ice. I was very surprised at the wandering present and it was difficult to keep on-line before turn in. Pucks were advised by my race shop and sourced from a fellow Rennlister.
My shop installed them in just about an hour. The next week I packed for Gingerman in South Haven, MI and off we went to test them out.
Gingerman isn't a very fast course but it's extremely technical with several multi-radius turns, off camber turns and elevation changes mid turn. It makes for an exciting time of trial and error. It's like the last guy jumping into a crowded orgy (is there any other kind?). Just try sticking your head in a few spots and eventually you'll figure out when to go for it.
However short, 125 mph is achievable on the back straight. The car was very planted tracking straight and true on hard braking now. It was a really good feeling to have that control back.
However, I was still boiling my fluid. It was very hot at almost 90 so I wasn't running as hard as I would have liked and kept revs to 6500 tops but brakes were still fading. After doing some research, I found I actually sourced the wrong Hawks pads. SMH It was my fault. I juxtaposed product numbers incorrectly when ordering. Turned out I had the touring pads and not the track ceramics. That was a potentially dangerous mistake I'll not make again. I performed a bleed to get any air out of the system and with a hard pedal, Pagid RS29s were sourced. I'll have those on for my next trip to the track.
Finally, I've been having trouble downshifting into 2nd from 3rd on hard braking for slow corners too. Not so much a problem at Road America but it was so bad I was forced to leave it in 3rd most of the time at Gingerman. After reading up on the Race/DE Forum here, it turns out this is a not uncommon problem with the supple liquid filled engine mounts allowing the engine/trans to move the 2-3 and 3-2 shifts out of alignment. So, Rennline semi-solid engine mounts were sourced from a fellow Rennlister and will go on this weekend hopefully.
not my photo
In the end, pucks are in, brakes are fixed and engine mounts will soon go on too before my next day on track.
Up next is a plan to change to a Krontec QR03 hub on my Cup Car wheel as I rid myself of the curly cord annoyance.
I have a 997.2 GTS as well with SS engine mounts and xmission mount inserts. Currently setup at -1.3 front, -2.5 rear camber and just corded my cup 2's on the outer edge in front after a few track days. My tech recommends adjustable LCAs in front (Tarett) so we can get more negative camber.
Looking at Tarrett and thinking of going with the GT3 LCAs with monoballs and solid bushings or the cup car LCAs which come this way. I saw all the comments about the pucks in this thread and am looking for things to look out for.
Not thinking about any further suspension mods at this time, but in the future will probably replace dampers down to other linkages. As I don't drive in winter and rarely hard rain, I'm not too worried about incremental deterioration of the monoball items.
05-15-2016, 12:08 PM
It was my fault. I juxtaposed product numbers incorrectly when ordering. Turned out I had the touring pads and not the track ceramics. That was a potentially dangerous mistake I'll not make again. I performed a bleed to get any air out of the system and with a hard pedal, Pagid RS29s were sourced. I'll have those on for my next trip to the track. 
