CGT Prices
01-17-2018, 04:52 AM
#2476
Track Day
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The Carrera GT clutch "problem" has nothing to do with the clutch. It has to do with the teeny-tiny flywheel inertia built into the engine. The low rotating mass allows the engine to rev like a motorcycle and supplies very little rotational energy to "dump" into a starting-from-rest event.
Plenty of drivers like to rev the engine a little (stores up some rotational energy) and then let out the clutch while the revs are still up. This driver-dependent technique usually can be gotten away with in cars with ordinary high-mass flywheels because the flywheel has enough stored energy to move the car from rest before it is all used up. Not so with the Carrera GT. If one used this technique with a CGT, one immediately stalled the car because all the flywheel energy was exhausted before the engine turned over a few revolutions.
Even Car and Driver summed up trying to get good 1/4-mile times or 0-60 times as "burn, buck, or stall". All from side-effects of that gorgeous, motorcycle-like, free-revving, low-mass flywheel.
The "idle-control" loop in the ECU was augmented to be able to keep the car running after clutch release with no throttle application as a driver workaround.
Plenty of drivers like to rev the engine a little (stores up some rotational energy) and then let out the clutch while the revs are still up. This driver-dependent technique usually can be gotten away with in cars with ordinary high-mass flywheels because the flywheel has enough stored energy to move the car from rest before it is all used up. Not so with the Carrera GT. If one used this technique with a CGT, one immediately stalled the car because all the flywheel energy was exhausted before the engine turned over a few revolutions.
Even Car and Driver summed up trying to get good 1/4-mile times or 0-60 times as "burn, buck, or stall". All from side-effects of that gorgeous, motorcycle-like, free-revving, low-mass flywheel.
The "idle-control" loop in the ECU was augmented to be able to keep the car running after clutch release with no throttle application as a driver workaround.
"Manual blipping before it grabs" won't work because the blipping only lasts a fraction of a second. The blip dies before engagement and the car stalls. To make blipping-before-grab successful, a more conventional flywheel is required so that there is enough energy left to keep the engine running when the clutch finally grabs. Adding throttle at the exact same time it grabs (not before) is what is needed.
The ECU programming doesn't "blip" anything. It merely struggles to keep the engine at idle speed when releasing the clutch tries to slow down the engine as it grabs. The ECU programming is powerful enough to smoothly maintain idle during move-off. The engine by itself would never experience that sort of trouble trying to stay running. Idling at rest and then maintaining idle as one releases the clutch is not the usual task of the ECU, so it required inventive programming.
I found that keeping my foot off of the throttle was fabulous for maneuvering around the garage or parking lot. I didn't like it so much for regular traffic starts. Since I was already used to driving cars with racing engines that had very small flywheels, I was easily able to adjust to the CGT engine/clutch requirements after only a few traffic starts. If one is new to light flywheel cars, it can take longer to learn how to coordinate gas and clutch.
Some early owners refused to learn how to move off from rest in a coordinated way and fried the clutch by slipping the crap out of it on start up. The CGT clutch is plenty capable of the task at hand, but it can be destroyed by slipping while lots of throttle is applied.
The ECU programming doesn't "blip" anything. It merely struggles to keep the engine at idle speed when releasing the clutch tries to slow down the engine as it grabs. The ECU programming is powerful enough to smoothly maintain idle during move-off. The engine by itself would never experience that sort of trouble trying to stay running. Idling at rest and then maintaining idle as one releases the clutch is not the usual task of the ECU, so it required inventive programming.
I found that keeping my foot off of the throttle was fabulous for maneuvering around the garage or parking lot. I didn't like it so much for regular traffic starts. Since I was already used to driving cars with racing engines that had very small flywheels, I was easily able to adjust to the CGT engine/clutch requirements after only a few traffic starts. If one is new to light flywheel cars, it can take longer to learn how to coordinate gas and clutch.
Some early owners refused to learn how to move off from rest in a coordinated way and fried the clutch by slipping the crap out of it on start up. The CGT clutch is plenty capable of the task at hand, but it can be destroyed by slipping while lots of throttle is applied.
Few people understand the GT's engineering meticulously , even fewer are able to articulate it so clearly !
01-18-2018, 12:17 AM
#2477
01-19-2018, 10:32 AM
#2478
Drifting
No offense ... looking at an 04 meeting with a tech who has worked on CGT's for years trying to find out if somethings changed later on the CGT system. Originally this system per Porsche was supposed to last 100,000 miles. The throttle blips up to an additional 2 - 400 rpm's that's a blip IMO and others click the link. The prior owner of my CGT was a race car driver not to be named - the clutch after 5500 miles showed little use and he stated that he accelerated from a dead stop after that conversation the salesman and prior owner suggested not to touch the gas and let the system do it's job. Purchased a brand new clutch off the shelf to have a spare and learn about the clutch operating system. It's the biggest issue with the CGT I think it deserves clarity.
https://www.6speedonline.com/forums/...ays-cgt-2.html
https://www.6speedonline.com/forums/...ays-cgt-2.html
Last edited by nuvolari612; 01-19-2018 at 10:52 AM.
01-19-2018, 11:15 AM
#2479
Addict
Rennlist Member
Rennlist Member
No offense ... looking at an 04 meeting with a tech who has worked on CGT's for years trying to find out if somethings changed later on the CGT system. Originally this system per Porsche was supposed to last 100,000 miles. The throttle blips up to an additional 2 - 400 rpm's that's a blip IMO and others click the link. The prior owner of my CGT was a race car driver not to be named - the clutch after 5500 miles showed little use and he stated that he accelerated from a dead stop after that conversation the salesman and prior owner suggested not to touch the gas and let the system do it's job. Purchase a brand new clutch off the shelf to have a spare and learn about the clutch operating system. It's the biggest issue with the CGT I think it deserves clarity.
https://www.6speedonline.com/forums/...ays-cgt-2.html
https://www.6speedonline.com/forums/...ays-cgt-2.html
01-19-2018, 04:00 PM
#2481
Rennlist Member
Sold for $715,000 at Gooding Scottsdale 2018 after buyer's premium:
https://www.goodingco.com/vehicle/20...-carrera-gt-3/
https://www.goodingco.com/vehicle/20...-carrera-gt-3/
01-19-2018, 04:07 PM
#2483
Burning Brakes
01-19-2018, 04:09 PM
#2484
01-19-2018, 04:13 PM
#2485
Burning Brakes
01-20-2018, 01:52 AM
#2486
As owners, we all want them to be worth $1 million already!
The CGT is still lagging behind a few other cars and the gap between the CGT and 918 is quite huge to say the least.
nonetheless, we’re off to a good start, let’s see where it takes us this year.
The CGT is still lagging behind a few other cars and the gap between the CGT and 918 is quite huge to say the least.
nonetheless, we’re off to a good start, let’s see where it takes us this year.
01-20-2018, 09:40 AM
#2487
Rennlist Member
Originally Posted by F40-r
As owners, we all want them to be worth $1 million already!
The CGT is still lagging behind a few other cars and the gap between the CGT and 918 is quite huge to say the least.
nonetheless, we’re off to a good start, let’s see where it takes us this year.
The CGT is still lagging behind a few other cars and the gap between the CGT and 918 is quite huge to say the least.
nonetheless, we’re off to a good start, let’s see where it takes us this year.
01-20-2018, 10:35 AM
#2488
Drifting
01-20-2018, 11:09 AM
#2489
Drifting
As a soon to be new CGT owner, I think the big-ticket maintenance has to be priced in. That, coupled with fairly big numbers and especially big numbers in US will always hold this amazing car back. But I bought it for the experience; not the investment. There are better cars to buy for 'investment'. But there's no other high-maintenance super car I have any desire to own other than the CGT. So I look at it as entry price (plus maintenance, insurance, storage) for the experience. I don't think it will depreciate a lot but I'm under no illusion that it will be a good investment. Too many (esp in US), too difficult to drive, too much maintenance.
High maintenance is just not true nor are the high production numbers - look at the F40 production and maintenance 50k is a drop in the bucket whereas 1/2 that on the CGT covers 30k miles and 15 years minimum.
CGT is the least expensive drivers car alive it's also 100% bespoke unlike the Enzo who shares the same engine with a 150k 599 or it's big brother the 599GTO that is priced at 700k.
Congrats on your purchase.
01-20-2018, 11:47 AM
#2490
Rennlist Member
For the crowd that is used to other Porsche products, it's high maintenance but agree the old Ferrari's are every bit as bad and usually worse. A 997 4.0 or 2rs is like owning a Prius practically. We get spoiled. But the same thing that makes the GT/rare 911s bullet proof and cheap to maintain is the same thing that makes them not as special as a CGT: ones the best of a mass produced product, the other a truly bespoke engineering marvel. It was my final box to check in collection. I'm looking fwd to taking delivery from a good friend who got to experience it and ready to pass along.
