Over the winter, considering some suspension upgrades for my 997.2 GTS (PDK, PASM, Sports Suspension, CLs). Used occasionally on New England streets, otherwise, AX and DEs.

Considering:
Springs (H&R) - given the existing sports suspension, any feedback? Too low? Too firm?

Stiffer & Adjustable Sways (GMR or OE GT3/GT2)

TPC PASM controller

Lighter wheels (Champion or Forgelines - upgrade to 12x19 and 9x19; perhaps 335/245 rubber.

Thoughts? Recommendations?

db

 

H&R wont help you. Only do that for cosmetics. PASM springs are just as good and rebound is better with the OEM struts on track. In fact rebound can be too much on track with aftermarket springs and OEM struts.

Lowering springs will also affect scrub radius and rear toe. If you lower, you'll need adjustable rear toe links.

I recommend also adding front GT3 LCAs to reset the scrubs radius monoball camber plates will help this too. OEM bushings are fine. Don't need monoballs on GT3 LCAs.

GT3 front and rear sway bars are a good buy. You'll need a spacer if you buy OEM. TPC sells custom sways that fit without the need for a spacer.

TPC DCS is on my list too.

Get lighter wheels with Nitto NT01.
Get front GT3 calipers and rotors. (also on my list).
Get SW bypass so people know you're coming.

Call it a day.

If it helps, here was a portion of my ever growing suspension part list:

 

H&R springs....I have them and can't tell the difference from stock in terms of ride quality. Steep driveways have to be negotiated at an angle but other than that, no issues.

For wheels, I've had Champion, HRE's and Forgelines on my 997's. All three are top notch quality, light weight wheels but the Forgelines are my favorites so far. Mine are 12x19 and 9x19 like you're thinking and they came with 325 rears and 245 fronts when I bought the car.

To me, those sizes looked too bulky on the car so when they wore out I stepped down to 305/235 which looks much better to my eyes. Yes...you lose a fraction of rubber against the road both front and rear but your center of gravity drops a fraction too so who knows what's lost and what's gained in handling. I suspect it's inconsequential for most of us.

 

If you're really only tracking the car ditch 19s and go with 18s. (PM or email me and I'll dig up the specs on mine for you). You can have two sets of wheels. Just keep your OEM 19 wheels if you're not driving it much outside track/DE and then have a dedicated 18 track wheel. CCW if you don't care about looks (even though they do look pretty good IMO). OZ HLTs are your next best option for the money. You can go spend $6k on wheels if you want but that's $$$ wasted if you're tracking them. Save it for instruction sessions....and more tires. Search for RL user mdrums on here too. He has provided a wealth of info in many posts and threads about his (former) GTS that was a great track car. His info pushed me in the right direction on my path to amateurness.

And I will respectfully disagree with Sandwedge about springs. They are cosmetic only and they look great. His look ****ing fantastic. But he'll be Tigger on the track. I've seen it. If you want performance you need adjustable coilovers so you can corner balance. Bilstien Damptronics are the best bang for the buck between $2.5k and $3k depending on where you buy them...plus installation. You can go with Ohlins for double that and up and up and up. TPC will be happy to sell them to you. But IMO if you need anything more than this just get a GT3.

For just DE and AX my list above is all you'll need for gay old times.

 

I guess I should have been more on point with respect to the H&R comments. All I referred to was "stiffness" or "harshness" in ride quality which seems to be a big concern to many. With that I can't tell the difference with H&R's compared to stock. I agree with you 100% that if improved handling and performance is what's important, coilovers is the only way to go.

 

The sway bars will make a huge difference in the handling, the stock PASM shocks and springs are quite good with the DSC control box. Give Tom a call at TPC and he can set you up with the sway bars and DSC. Start there and see if you want to change the springs. I was on the same path as you are describing and after talking with a lot of people I simply did the sway bars, lower control arms and DSC box and could not be happier.

I also agree to go to 18's for track use, you have some better tire selections and they are more cost effective too. Nitto NT-01 is a great tire for DE use. I bought a set of CCW wheels and they are bullet proof, the track is hard on wheels. I keep my Champion 19's for street use.

A good alignment is critical with some increased camber so the adjustable LCA's are needed up front to get you where you need to be on the camber.

The nice part about this set up is it retains the ride quality for the street but gives you the needed handling upgrades needed for AX and DE's.

 

GREAT advice and necessary or you'll wear through tires prematurely. I also have alignment specs used by four other GTS track guys. PM me if you ever want them.

 

Thanks for all the suggestions. Let me add a few more things...

I have had the car aligned specifically for the track with the help of a local porsche shop - within the limits of the stock suspension's adjustability.

I also have already installed a crosspipe/Center muffler delete.

In the clubs I run AX, I would like to stay in Strictly Stock class (PCA NER and NCR) which means Cup2s or Direzzas; R-compounds like the Nittos put me out of class.

Also, adjustable suspension components (that provide greater than stock adjustability - e.g., camber plates) put me out of class, however, it appears that sways are specifically allowed in class.

That being said, and within the above limits, it seems there is consensus developing around:

18's lightweight.
Sways
TPC PASM controller

Any other thoughts?

db

 

Can you change engine/trans mounts and stay in class? That may help in AX.

 

That's a good questions. I have Sport Chrono with PDK, thus I have the 'active motor mounts'. Are these replaceable in the way you suggest. Also, could you highlight the expected improvement with respect to AX (better later weight xfer?)?

Also, I looked up available sizes in Cup2s and Direzzas and neither has 18's in usable sizes for me. Seems like the 18s are only for R compounds like the Nt-001s.

db

 

Are you sure you have active engine mounts? I read they were only available in the Turbo and GTx cars.

Trans/engine mounts will reduce preload for weight transfer.

 

In terms of suspension, the GTS and the regular Carrera S will be very similar except for the centerlock wheels on the GTS. Other than that, what works for a C2S will work similarly for a GTS (rwd).

You need to decide how serious you are and then go from there. If you're competing in any sort of classed system (such as AutoX like you mention) then you have to choose your upgrades wisely and make the most efficient use of the "points" you take. Also, your setup for AutoX will differ than a setup for HPDE. Sway bars are the cheapest and easiest solution for adding more spring... but this essentially links the left and right wheels more, which isn't ideal, but the trade off you get could be worth it. It's also easy to adjust understeer/oversteer by adjusting the sway bars on either end to suit your style. If AutoX is your primary focus, then this is probably the best bang for the buck after wheels/tires/alignment since there's a lot of slalom and quick transitions in most AutoX courses. For a traditional North American road course however, I'd actually leave the sways stock and go with coilovers so you get new shocks, stiffer springs, and ride height adjustability so you can corner balance. On tracks where you have longer sweepers and less quick left/right transitions, higher spring rates and more independence between the axles is ideal so you can hit curbing/bumps/undulations with your unloaded wheels and not upset the outer wheels which is the side that is mostly gripping. The downside of this, though, is there's no easy adjustability for under/over-steer at the track besides changing tire PSI. Changing rake and corner balancing can achieve this as well, but you can't really do this at the track. If your local tracks are glass smooth, then thicker sways will be alright too, but again, it's a less efficient way of increasing spring rates because it links the suspension across the axles.

In regards to wheels - I originally had 18" CL's, but recently switched to 19" for better tire selection (read: more competitive). In 18's you really only get Toyo R888's or NT01's in 911 sizes which is fine for DE use, but they aren't very competitive from a classing stand point. They are considered R-comps, but their grip level isn't actually any better than modern ultra high performance street tires like the BFG Rival S, Advan AD08R, RE-71R, etc. They will perform better over many laps since they don't get greasy like street tires do after a while, and they are significantly cheaper, but that's about it - they're old tech. With 19's you can use Michelin Pilot Sport Cup 2's which are quite sticky but also a little expensive.

If you're more casual and just want to have a firmer, more responsive experience, then go for GT3 LCA's, GT3 sways and a very good alignment and call it a day. If you street drive the car a lot, don't go for spherical drop links with the sways since they'll rattle all day and it gets quite annoying - ask me how I know. The stock SPASM shocks/springs are actually quite good, so I wouldn't mess with them unless you were getting a serious coilover kit, not just some lowering springs which won't help at all since springs and shocks should be chosen together since shocks are valved with a certain springrate in mind. Just remember every suspension change you make for more "performance" usually leads to a loss in drivability (more noise, rattling, clunking, etc.).

 

This is generally true but I just want to specify that the rear sway on the GTS is actually thicker than the C2 or C2S counterpart.

 

Yeah, Porsche gave the GTS different sway bars than the C2S, but for aftermarket fitment purposes, what fits on the C2S will fit on the GTS (rwd). For a C4S/GTS4, the sways are different since the front axles have a driveshaft. I had TPC sways transferred from my C2S to my GTS, and eventually went back to OEM sways because they were simply too stiff when coupled with aftermarket coilovers.

 

I have a 2012 GTS...

#1 Bilstein B16 Coilover shocks for PASM...Brilliant! Had the H&R lowering springs but the car bounced due to the fact that the springs are not matched to the dampers...also with the new Bilsteins my car does not scrape the lip..strange as the car is just as low.

#2 Elephant Racing Sway Bars, control arms, bushings, drop links dog bone, strut towers. Basically got the whole deal.

#3 SPARCO Evo II US seats reupholstered in matching Porsche Leather (Mine is sand beige)

#4 GMG RSR roll cage

#5 Sabelt Harness (pull down style...NOT pull up).

#6 Coco Mats...why not!