Ceramics?
10-18-2014, 01:14 PM
#46
Nordschleife Master
10-18-2014, 01:55 PM
#47
+1 definitely not placebo in a car with decent steering feedback. I've noticed huge differences on changing wheelsets in the past.
10-18-2014, 01:56 PM
#48
10-18-2014, 02:52 PM
#49
Nordschleife Master
One question that I have never seen asked of those who think 30-40lbs of unsprung rotating mass is unnoticeable except in extreme track scenarios...
How much would be required before you would feel it in spirited street driving... 50lbs? 75lbs? 100 lbs? 1000lbs?
Seriously, just curious if there is a perspective on this....
10-18-2014, 03:28 PM
#50
Nordschleife Master
Ok, I've tried to stay away from this thread for as long as I could, but I have to throw in my 2 cents. LOL.
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
10-18-2014, 03:33 PM
#51
Rennlist Member
Join Date: Oct 2010
Location: Limassol, Cyprus and DFW, Texas
Posts: 4,636
Received 389 Likes
on
204 Posts
I can feel the difference in weight....in my wallet.
That being said, my current TTS has them and they are amazing. I wouldn't spec them for a car I tracked often.
That being said, my current TTS has them and they are amazing. I wouldn't spec them for a car I tracked often.
10-18-2014, 05:13 PM
#52
Nordschleife Master
Ok, I've tried to stay away from this thread for as long as I could, but I have to throw in my 2 cents. LOL.
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
No but seriously, in your opinion, how much unsprung rotating mass reduction would cause a feeling in a 3k car?
I was unfamiliar with that quote by Rohl... Was it a magazine article? Edit : I actually remember something like this back in the 2007 timeframe maybe, with gen 1 pccb
Thanks
10-18-2014, 05:21 PM
#53
Nordschleife Master
I bet if you replaced all the various control arms front and rear from the rubber bushing type to metal ***** like the elephant racing stuff...the advantages of lower unsprung weight may be more noticeable since the suspension won't be as compliant...stiffer. Of course you would also need to be driving the crap out if at the track. A suspension upgrade like that would be a bit rougher on the public roads.
10-18-2014, 05:30 PM
#54
Nordschleife Master
You ask a good question that I cannot definitely answer. I can only put out a guess, which really means nothing. My guess at which the threshold may be for noticing a difference in a car like the gt3 could be 20lb per corner?
As far as Rohl's comment goes, it was not in a magazine article (yet). It was from a conversation that a well known and respected magazine editor had with him.
I bet if you replaced all the various control arms front and rear from the rubber bushing type to metal ***** like the elephant racing stuff...the advantages of lower unsprung weight may be more noticeable since the suspension won't be as compliant...stiffer. Of course you would also need to be driving the crap out if at the track. A suspension upgrade like that would be a bit rougher on the public roads.
10-18-2014, 05:37 PM
#55
Ok, I've tried to stay away from this thread for as long as I could, but I have to throw in my 2 cents. LOL.
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
The placebo effect is EXTREMELY powerful.
30-40 pounds, even if it is unsprung? Not noticeable in a heavy (+3000lb) car that makes a lot of HP (475+). I would totally buy that you can feel it in a 2000lb, 120hp car. However, the GT3 is a heavy, high HP car. I couldn't notice it in a lighter car (2800lb spyder) with less HP (320hp). No way you'll notice it in a 991 GT3.
Before you guys call BS, Walter Rohl himself has said that he can't feel the weight difference with PCCB. If Walter Rohl can't feel the difference....
So the fact you couldn't notice it in the Spyder is actually supported by the scientific research and laws of physics.
10-18-2014, 05:57 PM
#56
Nordschleife Master
Actually, if you look at the scientific research it matters more in heavier vehicles. The greater the portion/ratio of sprung weight to unsprung weight the greater the impact is on suspension, acceleration, deceleration and steering. So the fact you couldn't notice it in the Spyder is actually supported by the scientific research and laws of physics.
The greater the ratio of sprung/unsprung, the greater the impact.
Therefore, a 5000 pound car will have a greater improvement in acceleration from a 40 pound unsprung weight loss than a 500 pound car with a 40 pound unsprung weight loss. Intuitively, that doesn't make sense to me. I would like to read more of the details on this. My guess is that there is some variable that is not being mentioned.
Last edited by orthojoe; 10-18-2014 at 06:16 PM.
10-18-2014, 06:03 PM
#57
Nordschleife Master
Lol. Unless I'm at the track, I'm always lurking around here.
You ask a good question that I cannot definitely answer. I can only put out a guess, which really means nothing. My guess at which the threshold may be for noticing a difference in a car like the gt3 could be 20lb per corner?
As far as Rohl's comment goes, it was not in a magazine article (yet). It was from a conversation that a well known and respected magazine editor had with him.
You make a great point here. I'll buy into that!
You ask a good question that I cannot definitely answer. I can only put out a guess, which really means nothing. My guess at which the threshold may be for noticing a difference in a car like the gt3 could be 20lb per corner?
As far as Rohl's comment goes, it was not in a magazine article (yet). It was from a conversation that a well known and respected magazine editor had with him.
You make a great point here. I'll buy into that!
I think you may be referring to the Chris Harris interview with Walter Rohl back in the 2007 timeframe. He actually later came back and made different statements in 2008. But regardless, I don't think he has made any such statement about the current or even last generation of PCCB. I put a lot of stake in what he says, that's why you got my attention for sure with that one!
10-18-2014, 06:07 PM
#58
Nordschleife Master
May 2008 GT Porsche magazine
Chris Harris: "What are your thoughts on PCCB"?
WR: "First I thought it was too expensive then I had it first on a 996 GT3 which I used for one year and did 30,000km. Just before I let the car go, I took it for a service and they said the brakes were like new. But then I go very gently with the brakes and since then I always have PCCB. The car rides much better & you can feel the weight not being there".
Chris Harris: "What are your thoughts on PCCB"?
WR: "First I thought it was too expensive then I had it first on a 996 GT3 which I used for one year and did 30,000km. Just before I let the car go, I took it for a service and they said the brakes were like new. But then I go very gently with the brakes and since then I always have PCCB. The car rides much better & you can feel the weight not being there".
10-18-2014, 06:13 PM
#59
Nordschleife Master
ok, thanks for your thoughts. I think you may be referring to the Chris Harris interview with Walter Rohl back in the 2007 timeframe. He actually later came back and made different statements in 2008. But regardless, I don't think he has made any such statement about the current or even last generation of PCCB. I put a lot of stake in what he says, that's why you got my attention for sure with that one!
10-18-2014, 06:24 PM
#60
Nordschleife Master
I would have done it for no brake dust and to be different... I have never had them before... many Porsches, always the irons, no problems for sure... we will see if this becomes my only set or if I like them for street spirited driving in the TX hill country!