BTW, following is the report of that review that I kept talking about: First time that a shoot-out of 997 Turbo's is done by a legit US mag! I was wrong in one aspect, the result was closer than I had remembered. While the TPC Turbo was faster at the track, the AWE Turbo was considered the winner on the street. (Tire comment edited, thanks.) Note also the TPC has adjustable metallic/heim joint drop links, a significant difference.

http://www.tpcracing.net/articles/a-...-super-powers/
Hardware:
One look at the stance of these 997s is enough to know that they’ve got chassis upgrades. The AWE 750R’s suspension modifications are pretty modest, consisting of Bilstein Damp­tronic coil­-overs, a 24-mm H&R adjustable rear anti-roll bar set to full soft, and GT3 two-piece lower front control arms. TPC’s 775B has more extensive changes: Bilstein Damp­tronic coil-overs with custom valving and custom springs, a front anti-roll bar that’s 50 percent thicker than the stock piece, a rear anti-roll bar 30 percent thicker than stock, TPC’s adjustable drop links, 997 GT3 Cup control arms in front (machined to fit), and front-end geometry changes to TPC specs. While AWE was running stock ceramic brake pads for the 750R’s factory PCCB brakes, TPC chose Pagid Yellow (RS19) pads for the 775B.

Handling:
Through the curves, AWE’s 750R displays a more agile character. It feels lighter (it’s not). Its steering feels faster (it isn’t). Interestingly, unlike the 775B’s custom-valved and proprietary-sprung Bil­stein Damp­tronic electronically adjustable suspension, the 750R is suspended by off-the-shelf Damptronics. Some difference in feel on the street may be attributable to the car’s much-lighter PCCB ceramic-composite brakes and, more likely, its Michelin Pilot Sport Cups versus the TPC 775B’s Toyo R888 tires.

Conclusion:
At the track, Murry and I agree: TPC’s 775B takes it — and not just because of the faster lap. No, it’s because of its better level of driver comfort at the limits.
So, which one? If your primary interest is street use, you can’t go wrong with either car, though we’ll give a slight nod to AWE’s 750R for its fun factor and more engaging experience. If your interests lie at the track — or if you are looking for a clear dual-purpose car — the TPC 775B is a better-rounded package thanks to its smoother power delivery and confidence-inspiring handling.

There is a track time analysis that I will post later.

 

I'm 95% sure the awe car was running cups fwiw.
Can, if you like R cmpds on the street, wait until you try some R6 Hoosiers on the track....essentially crack. One of these days you'll get sick of canyons and come on over to the dark side, it's only a matter of time.

 

You mean before he gets arrested JK .
Can i'll mill over your posts and respond tomorrow. Sorry mate, weekend duties call...

 

^^^Oddly enough, the only time that I "got in trouble with the law" was when I was not intentionally speeding and therefore not paying attention. Got one first day I got the Cargraphic. I was revving to hear the exhaust, and sort of forgot how loud it was. The police officer was really mad since it took a while for me to recognize his siren. "Didn't you HEAR me??!!" he said.

 

I dunno, if the cops catch you driving significantly over the limit on curvy roads around here, it's called reckless driving and your car gets flat towed away. That would be my concern about driving 'hard' on the street. I save it for the track. I think that's what Paul was getting at.
GO CHIEFS!

 

^^^^Chris, that was my light-hearted joke with Paul -- I will edit that post now, thanks . Please don't make assumption/accusation about how I drive (dangerous on public forum) and could you express your opinion without sounding somewhat like an ostentatious ***?

Re. canyon vs. track driving, personally I think if we race in a tight course you might just see my back end only :-) but I guess one will never know. JK, I am only a beginner level amateur driver.
But let's get back to topic at hand, my lively debate with Paul about underdamped lowering spring with possible stability problem, please?

 

Great googlie mooglie...7 straight post season losses...I can't take it any more.

 

#$@%@ the Chiefs need a QB
Can...I guess I struck a nerve or something, I never mentioned you, I was referring to Paul's post and the laws around here.
I think you should lighten up.
c

 

OK Can, am back... Btw i was just kidding about you getting yourself arrested....so please no more blood on the floor over that...i shouldnt have said that in hindsight looking at what ensued, and accepted that you are being very good and just driving the posted limit on these canyon expeditions .

Anyways.... I read what you posted re the comparo or shootout whatever and what i read into it was the TPC is the more liveable/forgiving between those two set ups. And i say that with respect to the car being easier to manage at high speeds, whether street or track. So it goes without saying it must ride better now the shocks have been modded along with the coils. Obviously TPC has corrected a few things that needed correcting for one of a bettter word. I don't mean to bash the Bilstein product as they are obviously a good product for Porsche to use as an oem supplier but the point i was getting at was the aftermarket package doesnt appear to be fully sorted like Porsche has managed and, "specified their design set up" for Bilstein to supply to P's car assemblers. Also unless these AM set ups are installed by seasoned suspension installation experts they may develop problems. Ride heights causing too harsh a ride possibly being a key one of them along with clunks and other odd noises. Now maybe my Billy CO's were set too low which made them jiggy(they were set@ 25mm lower than stock)...i dont know....but they sure rode rough as bags....too rough for my liking and too jiggy for a street car. They made the seat springs overtake the suspensions job plus the car developed squeeks and rattles from all over the place from being so crazy taught and jiggy. Granted the Billy coilovers definately sharpened the cars steering up, not that it was a dull car to begin with by any stretch, but the ride was simply not resolved enough for a P car least of all one that sees 85% of its use on the street which is the case for most of these cars....yours included i imagine?. So that said, unless i could audition a car set up with out of the box PSS10"s here that i could test on the street (so to give the nod of approval) then i would prefer to hedge my bet on say a GMG lowering spring set up....not that i can really afford to go much lower than stock with all the stupid speed humps that have been going into my local area of late....im scraping my front on these things stock .

Anyway In so far as your point that lowering springs are taking the stock pasm shocks out of their correct stroke range/position which can cause problems and failures etc (which makes logical sense) then surely the same should still apply to the PSS10 shockys. Why would the PSS10"s be able to operate perfectly regardless of height settings and where the pistons wound up in the allowable range especially if the heights were set @ their lowest point and, the stock pasm shocks with lowering springs not? Its the same situation really. If the PSS10 piston stroke is being equally altered positionally as what would happen with a set of lowering springs on the stock shocks then logically there must be a negative somewhere unless the valves are adjusted to compensate for the altered piston travel from being set at a low position....(possibly why TPC has modded the valves?). So that said why would a set of Pasm shocks develop problems with lowering springs if a set of PSS10 shocks can survive at their lowest setting without valve modding? Doesnt make sense really .

I note TPC has altered the valving to achieve a result satisfactory to their particular liking (which is also pretty well everyones liking that tests these two set ups) but am not clear on exactly what height setting they chose....how low etc. So assuming both the stock pasm shock and bilsteing PSS10 shock are physically much the same dimensionally then the valving must have a lot to do with how the shock behaves depending upon the position it ends up in its stroke range, ultimately determined by the ride height and/or spring.

Whilst i agree that sways and links will make the car feel sharper I still believe that the car in stock trim with a really good track focused alignment will still deliver in the hands of most reasonably skilled drivers on the track.....while still allowing the car to fulfill its DD duties. Finally I also think a precurser to any mod should be P driving school imho.

 

Paul, yes sir, I always obey the law! You are asking outstanding questions and let me try to answer them one by one. Any pro please correct me as needed -- I don't claim to be correct always and I only know suspension tuning at a basic level.
First let me clarify again, the point is not whether lowering springs "work" (yes), but whether it is a compromise and there might be better choices. Also, the stock car is fine for some people and I am never into convincing anyone what's good for him! All I am saying is this: *If* you think the stock is soft, here are the choices, here are the reasons.

1. Rod position within the coilover: The key difference between stock and after-market coilover, is that the after market coilovers are designed to be height adjustable, the stock is not. It's that simple. The design/construction/etc. for a height adjustable coilover is not the same as the stock unit.
The specs of any given coilover are given over a range of operating height -- outside of that height the damping force is any body's guess.

With lowering spring, not only you're lowering the rod to where it should not be, you change it by a significant value of 24mm (typically). If you talke to the manufacturer of the stock unit, Bilstein, they will emphasize that the stock units are not designed for any of this. Even more important, this height lowering is not adjustable: if you car scrapes unacceptably more as a result, you are basically SOOL.

2. Re-valve: I assume you're asking here about revalving and altering the dampening forces of the coilover? For example say an after-market coilover has spring rates of 400/600, and has dampening forces appropriate for those spring rates; the manufacturer will tell you something to the effect that it's ok for you to use different spring rates, up to say 600/800 (for example). Beyond that, they would recommend for you to re-valve.
All of the after-market coilovers have dampers that are designed with a range of appropriate spring rates in mind. For example the Moton/JRZ are designed for use with very high spring rates in mind, like 400/600 and above, the Bilstein Damptronic for middle range of 300 to 700, etc.. Not one is "better" than the other, they are just different. In contrast, the stock coilover is designed for a single spring rate, the stock's low range. This is where the mismatched underdamping comes from, to keep in easy to understand terms: the "mid level" spring is matched to "low level" damping. While you could get away with it, just know that it's not what the manufacturer advises. It is a compromise and very likely the reason for the unstable, floaty sensation that people have complained about w/ lowering springs.

3. The TPC coilover system: I know the review says so, but to the best of my knowledge, the reviewer might have been off. The TPC coilover change involves the front spring rate and revised PASM algorigthm, it does NOT involve re-valving. Casey and anyone at TPC please correct me as needed. Regardless, whether it is re-valved or not, for our intended use of this car, I do not believe it to be a big deal.
Now if you are running 800/1000 front/rear, then it's a different matter. But then, by then you really should be in something like Moton/JRZ, Motorsports Bilstein, etc., not the Damptronic.

In other words, IMHO, the key to the TPC system is not the revalving, but a. the stiffer front spring rate, and b. how the system is designed and tested together by pro-tester, at the track.

4. Paul, as I have mentioned, I do not know why but your experience in the C2 is not representative of the Turbo Bilstein. See the review above and the many Bilstein reviews on this forum.

5. Why I fell in love with the TPC system even though I haven't used it? And also my opinion on how I think it would compare vs. Bilstein Damptronic. I'll talk about that next, but do I think TPC engineers know a secret Bilstein does not, or are more talented? Absolutely not! Remember Bilstein is a huge engineering group and are the same people who are involved with GT2/GT3 suspension. What it is is that Bilstein is designed for a larger group of customers, whereas TPC is designed for a much narrower range of customers. TPC could afford to specialize, and apparently did a hell of a good job, but for some people (not me), the basic Bilstein might well be the better choice.

 

I'm resurrecting this thread to answer Can's original question.

Member lithium1330 posted this...please give him + rep for doing so.

https://www.6speedonline.com/forums/...ml#post3722111

 

Thanks Bob as always. "Super" moderating indeed.
I am now back to regular street tire (Mich PSS) but this will come handy if I decide to use R comp again; the constant TPMS alarm did unnerve me while those Pirelli Corsa's were on .

BTW, LOL at the "onstentatious *ss" comment above in post 66.