A little background.... this is my 3rd 911 (first turbo) and my 5th Porsche. I'm pretty familiar with the cars but the Turbo is driving me a bit crazy and I am wondering if there is something wrong with my car? So hopefully those with more knowledge than me on the subject will chime in.

My last 911 was a .2 GT3 and I loved it. I never had any issues with throttle over steer like I do in my Turbo. The Turbo is at times a tad scary as the rear end will step out in corners with little to no provocation. It's mostly on tight corners vs wide sweeping corners but it's always there to a certain degree. I feel the car under steers WAY too easily and that this is what's causing the over steer problem. By this I mean the car plows into corners, the weight transfers forward and the rear gets loose causing the rear to come around.

Also the cars factory suspension is crap. It floats too much, bounces too much and feels under sprung and over damped. It doesn't control body lean AT ALL! It's like the shocks and springs are NOT matched and/or tuned to work together. It doesn't matter which PASM mode I am in, none of them are even close to the smoothness as what my GT3 was. My GT3 was WAY smoother in all PASM settings and didn't have any of the issues I am complaining about.

I have read and responded to many threads on this forum about suspension upgrades and my thoughts are to get the GMG springs and sway bars or go with the Blistein Damptronic. I am on the fence about this right now.

So what I am asking here is if anyone else has/had this issue with your Turbo? Is what I'm experiencing "normal"? Is the rear end coming out REALLY this easy and common? If it is common, then I'll stop complaining and upgrade my suspension as I will then know that this is the issue.

Background on my car.... It's a 2011 Turbo, PDK, PTV, Sport Chrono with 13k miles on the clock. It's a one owner car (2 now!) and was always serviced at the same dealer. I bought it about 6 weeks ago and it's CPO'd. It's super clean and in like new condition. The tires (MPS PS2's) are in good condition and have probably 60% tread on them. I do not know how old they are however. I do not know when/if the last time an alignment was performed either.

Other than this I love the car and hope that what I am experiencing is easily fixed and I can get close to the handling I had in my GT3.

Thanks guys!

 

I also came from a GT3 (a .1 with full Champion suspension) and I also found the turbo to be insanely easy to lose the rear on. It was 2 things adding together:
1) I was driving it like the GT3. It's a GT car, you need to adjust your driving style a bit
2) Even with some adjustment, the suspension is still crap for aggressive driving like you're used to in the GT3. Springs and sways will greatly help this and give you the more aggressive feel you're after (and help keep the rear in line). I found that I needed way more front bar than in any other car I've had due to my driving style. You may be in a similar situation if the GT3 handling characteristics were to your liking.

Edit: Alignment will also help. Get alignment recommendations from GMG or Champion. I like mine with some negative camber (-2 front, -1.5 rear IIRC). Adjust to your desires.
Tires might help as well. Skip the PS2s and get Michelin Pilot Super Sports. Sport Cups for track days. That will help by giving much more grip.

 

great advice. i too was a bi dissapointed with 997tt suspension and i dont track my car. its too soft and i dont feel like i trust it very much in tight fast corners. understeer induced oversteer is only fun if you have a lot of space to play around otherwise its not pleasant.

 

Two things to note before you start tinkering with the suspension, (1) driver correction error and (2) tire pressure. First I'm assuming you took these same corners at the same speeds in the TT as in the GT3, if so you WILL experience understeer in the TT relative to the GT3. Porsche calibrated the TTs to induce understeer in corners taken at speed to counter customers who didn't understand the physics and implications of a rear weight-biased 500HP, torque monster that is the 911 turbo. Your natural instinct is to steer further into the turn thus inducing oversteer (exacerbated if you lift off the throttle).

Tip #1 don't attack the corner as aggressively (vs. the GT3), if you still choose to then don't over correct (i.e., fast hands), angle the steering wheel slightly and in lieu of easing off the throttle, feather your brakes. the TT has a different geometry, acknowledge it!

Tip#2 as simple as it sounds, check your tire pressure. Chances are that you are at factory recommended tire pressures 37/44 (cold) under a "Full Load" setting. Check your settings, adjust to summer tires, partial load and "zero" out (typically a reduction of about 2-3psi when cold)! Let me know how those corners feel afterwards, if you had not already done so.

While suspension mods will improve your car's handling, unless you're a serious canyon carver or track your car, minor changes to your driving style (vs. the GT3) and tire inflation should make a huge difference.

https://www.6speedonline.com/forums/...l-setting.html

 

I guess it's all relative to what you are comparing it to. You're comparing the turbo suspension to a GT3 (a monster in that department). In my case, I love the suspension, but I came from bmw world.

I too would love to tighten it some more (tighter is always better!) and was thinking about GMG springs and sways with a bit more aggressive camber. My only concern is that if I go this route, what else would need to be addressed because once you start fiddling with the suspension you expose other weak points and it becomes a never ending quest.

-Jose

 

I have a set of bilistein coilovers and H&R Sway bars that I'm about to list for sale. 2k miles on them and they are in as new condition.

Here is a link for more information on them.

http://www.fvd.us/us/en/Porsche-0/99...ampTronic.html

 

Completely agree with everything you have said. I HATED the stock 997.2 suspension. And then adding 200 HP, it got worse...way worse, particularly with the rear end coming out.

Unfortunately there is no cheap solution. Mismatched GMG springs aren't going to help. Bilstein's aren't going to fix your problem.

You want to get rid of that float? You want the rear to stay planted? You want the car to lean just right and provide proper feedback to inspire confidence? Basically you want it to handle like a GT3 right? While that may be difficult to achieve, you can certainly make it handle like an AWD GT2. It has been done before. In order to achieve this, you need properly set up coils with GT3 RS sways, dog bone/end links to keep the rear end planted, longer lower control arms to widen the track, camber plates and a corner balance alignment from a shop that actually races Porsches to set it up to your driving specs.

 

Yes. Yes. Yes. YES! Point me in the right direction please!!
And why do you say "mismatched GMG springs"?

And to address what others have said, I have played with tire pressure and have settled on cold psi 34F/37R and that has dialed some of the oversteer out. I'm up for suggestions if anyone feels it should be different.

Yes, I have been driving it like my GT3 and quickly realized I can't do that. I've tried to take my favorite roads and turns as if I were driving my GT3 and have had a few "OH $HIT" moments. I hate that the front end will bob up and down during a fast sweeper and the suspension gets so unsettled. My GT3 was damn near perfect for me, so yes, if I could get close to that I would do it.

I'm at least relieved to read that my issues are not solely mine because I was beginning to think they were. I figured a lot of it was because of the Turbos HUGE amount of torque breaking the rear wheels loose with the same tire size of the GT3 but it was such a drastic upset that I thought there might be something wrong with my car.

 

A driver once told me you have to dive into corners less aggressively with the TT (compared to the GT3) but put more power down through the turn to keep the weight at the rear and keep it planted. The 4wd helps keep the car going where you want it. But I'm not a track junkie so take this with a grain of salt

 

Is there a shop close to you that builds Porsche race cars? Because that is your best bet. If not, you could probably consult with BBi Autosport or GMG on what you would like to achieve and they could order you a customized package and ship to you. But a good shop will still need to install it, give you a proper corner balance alignment and set up the damp/rebound coil settings to your liking.

 

Check out this thread
Harris at TPC may have what you need along with sways dog bones springs etc


https://www.6speedonline.com/forums/...ension-18.html

 

funny... i said the same thing when i first picked up mine and i was coming the supra world. it is so weird how when coming around a curve with decent speed and you hit a bump the front is so uneasy.... feels like it doesn't want to plant. Someone said add some weight to the frunk and see if that helps. 40 pound bag of kitty litter was the recommendation.

what are you guys running for air pressure. mine is 34 and 39 cold.

 

Currently I am at 33f/37r and have been playing with the tire pressure for at least a week. A lot of my snap oversteer is gone and the rear puts power to the ground more now but I'm not sure at what cost. With the rear tires being 7psi lower than Porsche recommends, I don't know how much quicker the insides of my rear tires will wear.

I will add that the pressure gauge I use and the TPMS in the dash show totally different readings. With my 33f/37r reading on my hand held gauge the TPMS in the dash displays 31f/34r.

 

The Porsche TT is a GT car, not a sports car and as a GT car the stock suspension is great. If you want a turbo sports car, get a GT2.

 

Suuuuuuuuuuuuure........ if only I had an extra $100k laying around.