991 GT3 Market watch

[luzzo]

1 hour ago, Redracn said:

Shame that is not the case. The initial batch had a rod issue that was third party and a full recall was done. The valve-train issue is a design problem that has a different sized bandaid on it depending on the engine revision. Having the latest engine is not a fix.

Interesting.  I haven't exhausted all reading on this, but from what little I have read, I thought the G series engine resolved the issue?   Also, does that mean if Porsche have bothered to replace an engine, the replacement may also fail with similar issues? 

 

[NBTBRV8]

7 minutes ago, luzzo said:

Interesting.  I haven't exhausted all reading on this, but from what little I have read, I thought the G series engine resolved the issue?   Also, does that mean if Porsche have bothered to replace an engine, the replacement may also fail with similar issues? 

 

There is no doubt that the engine failures have tainted the .1, have Porsche resolved the issue?  Well only time will tell, there are very few motor failures on the .1 RS all of which had the G series motor and there are very few reports of G series motor failures.  There is a very long thread on Rennlist and many of those guys track their cars hard and so far no common trend of further failures.

I'd be super nervous if I had a car with an F series motor and the car wasn't eligible for the Porsche extended warranty.

 

[wilson59]

4 minutes ago, NBTBRV8 said:

There is no doubt that the engine failures have tainted the .1, have Porsche resolved the issue?  Well only time will tell, there are very few motor failures on the .1 RS all of which had the G series motor and there are very few reports of G series motor failures.  There is a very long thread on Rennlist and many of those guys track their cars hard and so far no common trend of further failures.

I'd be super nervous if I had a car with an F series motor and the car wasn't eligible for the Porsche extended warranty.

 

I have heard of quite a few failures on the .1 RS in fact enough for me to steer clear of them . From what I understand the G series motors essentially made it into what the Rs was using to resolve the issue . 

Correct me If I am wrong 

14 minutes ago, luzzo said:

Interesting.  I haven't exhausted all reading on this, but from what little I have read, I thought the G series engine resolved the issue?   Also, does that mean if Porsche have bothered to replace an engine, the replacement may also fail with similar issues? 

 

There would be a strong argument if Porsche thought the issue was resolved they would have used the same motor in the .2 cars with a bigger capacity as the RS .1 .   

[NBTBRV8]

This is a good thread with countering views:

https://www.pistonheads.com/gassing/topic.asp?h=0&f=230&t=1791741

 

[Redracn]

11 minutes ago, wilson59 said:

There would be a strong argument if Porsche thought the issue was resolved they would have used the same motor in the .2 cars with a bigger capacity as the RS .1 .   

For Porsche to spend a lot of money on the .2 engine gives a very clear indication that they were not confidant in using the .1 engine valve-train or crank going forward. The .1 RS is also helped by its lower rev limit. While not much lower it still makes a big difference to a valve-train. 

[wilson59]

7 minutes ago, NBTBRV8 said:

This is a good thread with countering views:

https://www.pistonheads.com/gassing/topic.asp?h=0&f=230&t=1791741

 

Looks like this guy seemed to be on it 

As co-founder of the "GT3 World Wide Action Group" (google it) back in 2014 on this issue with Sunil lets be clear here.

I used my 991 GT3 on the track from 2014-2017 (sold in May 2017) and required three engines. E, F and G1. I believe the car has subsequently had a fourth G6 engine fitted....

The issue with the MA175 engine (and this applies to the variants in the 911R and 991.1 GT3RS) is an architectural one. The hydraulic tappets "pump down" when run above 86-700 rpm for sustained periods. This in turn means that the pressure that the finger follower is contacting the cam lobe with is varying in pressure. This variance creates bruising on the DLC coating on the finger follower whih eventually scabs and falls away allowing the steel cam lobe to start scoring the folloers pad. The ECU on these cars measures individual cyclinder timing and will put the car in limp mode should the tollerance be exceeded.

PAG tried addressing this with DLC coated cam lobes to meet the metal hardness of the already DLC finger followers and ally the bruising. They also tried new software with each engine interation (F and G) to regulate a higher oil pressure to try and feed the hyraulic tappets more oil. Later they tried extra oil galleries in the G series heads to help again with feeding more oil but unfortunately these measures mean that certain cyclinder valve train recieved more oiling than other cylinders. the issue is occuring in the high 8700-9000 rpm range.

I ran my car in Sport Auto mode on the track for three seasons (the program shifts at 9000 rpm so I guess on the average 6 session track day I was hitting the limiter over 400 times a day). You can do the math over 10-20 track days....

For the 991.1 GT3RS they tried a new method to erradicate the issue. They reduced the max RPM to 8800 (but only in 1st gear so they could claim the headline number!). The engine then brings the maximum rpm down incrimentally to approx 8650 in top gear! they also incorporated the DLC coated cam lobes and the additional oil galleries of the G series engine heads. Whilst issues with the 991.1 GT3RS engines are much rarer, they have still occured in instances where the car has been used in Sport Auto mode repeatedly at the track although data points here are very hard to establish.

For the 911R they opted to get even more conservative with a 8600 hard limiter! This should in theory eliminate the issue as with a manual box its very difficult to shift above 8400 on track in the heat of the moment without hitting the limiter in any case.

The 10 year warranty is a band aid. The engine was re-designed with solid lifters in the 991.2 variant and these were a direct result of the Cup car test program after the weakness was identified in the 3.8 road cars MA175 engine. The 3.8 was a 'toe in the water' excerise which lead to the 4.0L engine we see in the 911.2 GT3/RS and Cup cars today.

Personally I would have no issue in buying a 991.1 GT3 if the price were right and I was not using the car extensively on the track in sport auto mode. Short shifting in manual mode would reduce the issue womewhat. The issues are only occuring due to oiling at the high end of the RPM rage which is rarely breached on the road in any case.

However if I (as I am) using the car primarily for 15 or so full and hard track days a year I would look to either accept that I will likely need at least one warranty engine replacement during my tenure (and I would be sure to sell before the 10 year mark) or else I would pay the extra and opt for the 991.2 with the revised 4.0L engine.

All that being said its also early days for the 4.0L engie in the 991.2 variants although at this time i have no reason to believe the issue above exists (technically the solid lifters have addressed this and also benefited the engine by allowing a lower oil pressure to be used and this less parasitic losses due to less work for the oil pump and less draw on teh crank).
 

[Shedpest]

47 minutes ago, wilson59 said:

I used my 991 GT3 on the track from 2014-2017 (sold in May 2017) and required three engines. E, F and G1. I believe the car has subsequently had a fourth G6 engine fitted....

 

 Holy f#ck, I've change my underwear less than it had engines between 2014-2017

[luzzo]

4 minutes ago, Shedpest said:

 Holy f#ck, I've change my underwear less than it had engines between 2014-2017

Captain Stinkypants..!  

💣

[StevepGT3]

I’d be running high zinc oil and reprogramming  the rev limiter Down 500 rpm if I got stuck with one when the musical motor swaps stop 

[DJM]

5 hours ago, StevepGT3 said:

I’d be running high zinc oil and reprogramming  the rev limiter Down 500 rpm if I got stuck with one when the musical motor swaps stop 

Turn it up to 10,000 and make sure it pops during warranty.  And then sell with a brand new engine 👌🏻

[Peter M]

8 hours ago, wilson59 said:

...The issue with the MA175 engine (and this applies to the variants in the 911R and 991.1 GT3RS) is an architectural one. The hydraulic tappets "pump down" when run above 86-700 rpm for sustained periods. This in turn means that the pressure that the finger follower is contacting the cam lobe with is varying in pressure. This variance creates bruising on the DLC coating on the finger follower whih eventually scabs and falls away allowing the steel cam lobe to start scoring the folloers pad. The ECU on these cars measures individual cyclinder timing and will put the car in limp mode should the tollerance be exceeded....

That's not a convincing failure mode analysis.

This in turn means that the pressure that the finger follower is contacting the cam lobe with is varying in pressure. - So what?  A valve spring does that on every opening and closing of the valve.

This variance creates bruising on the DLC coating on the finger follower whih eventually scabs and falls away allowing the steel cam lobe to start scoring the folloers pad. - What bullshit.  Bruising?!  Scabs?! Please!!!!!  Is he talking about his genitals?

The ECU on these cars measures individual cyclinder timing and will put the car in limp mode should the tollerance be exceeded....- How does failure of the cam lobes and followers effect cam timing variation.

I'm not convinced this guy knows enough to provide an opinion of any value.

[njb]

On 01/09/2020 at 20:20, NBTBRV8 said:

The prices show no signs of abating.

Check out this 2018 Porsche 911 GT3 991 Manual MY18.

https://www.carsales.com.au/cars/details/2018-porsche-911-gt3-991-manual-my18/SSE-AD-6804358

Prices aren't dropping.

[Lindo]

Worst recession since great depression and people rush out to buy a Porsche and sellers start putting their prices up. Crazy times.

[wilson59]

1 hour ago, Peter M said:

That's not a convincing failure mode analysis.

This in turn means that the pressure that the finger follower is contacting the cam lobe with is varying in pressure. - So what?  A valve spring does that on every opening and closing of the valve.

This variance creates bruising on the DLC coating on the finger follower whih eventually scabs and falls away allowing the steel cam lobe to start scoring the folloers pad. - What bullshit.  Bruising?!  Scabs?! Please!!!!!  Is he talking about his genitals?

The ECU on these cars measures individual cyclinder timing and will put the car in limp mode should the tollerance be exceeded....- How does failure of the cam lobes and followers effect cam timing variation.

I'm not convinced this guy knows enough to provide an opinion of any value.

Dunno it is not my field of work  . Feel free to add  or let us know where he is wrong .

 

[Redracn]

1 hour ago, Peter M said:

That's not a convincing failure mode analysis.

This in turn means that the pressure that the finger follower is contacting the cam lobe with is varying in pressure. - So what?  A valve spring does that on every opening and closing of the valve.

This variance creates bruising on the DLC coating on the finger follower whih eventually scabs and falls away allowing the steel cam lobe to start scoring the folloers pad. - What bullshit.  Bruising?!  Scabs?! Please!!!!!  Is he talking about his genitals?

The ECU on these cars measures individual cyclinder timing and will put the car in limp mode should the tollerance be exceeded....- How does failure of the cam lobes and followers effect cam timing variation.

I'm not convinced this guy knows enough to provide an opinion of any value.

The guys conclusions are essentially correct even if his terms are not as good as they could be but anybody that knows even a small amount (that would be me) about this stuff will understand what he is saying.
So the pressure exerted on the hydraulic adjusters, which increases with RPM, causes them to compress  and hence the valve clearance to increase ( lots of slop /free play). The followers then loose contact with the cam and recontact with a high impact force. This fatigues the surface of the follower and camshaft and essentially the fatigued and work hardened fragments break away pitting the cam and or follower. It’s all down hill from here. The valve-train is far more dynamic than spring pressure as inertia of all reciprocating parts plays a major roll in the forces involved. The cam profile is carefully designed to control the forces involved and while everything is following the cam profile all is good but if for any reason components no longer follow the cam profile such as too much valve clearance or valve float the forces can rise dramatically. I wouldn’t be relying on high zinc oil to help either. 
 

So how do you explain that the first sign of this problem is the check engine light coming on?
Then the cause traced to a damaged cam lobe and follower?

By timing he means the ignition as the ECU is most likely detecting engine vibrations that are higher than normal  (horrible grindy sound of stuffed cam lobe and follower) via the knock sensor that it can not remove by retarding the ignition. Well as an ECU programmer that’s my opinion. 

[luzzo]

New listing 2018 991.2GT3 4300kms ($319,995) CTS

https://www.carsales.com.au/cars/details/2018-porsche-911-gt3-991-manual-my18/OAG-AD-19124153/?Cr=0

[NBTBRV8]

12 minutes ago, luzzo said:

New listing 2018 991.2GT3 4300kms ($319,995) CTS

https://www.carsales.com.au/cars/details/2018-porsche-911-gt3-991-manual-my18/OAG-AD-19124153/?Cr=0

That is a reasonable spec and not unrealistic asking price which put some of the other cars on the market to shame.

[luzzo]

2 minutes ago, NBTBRV8 said:

That is a reasonable spec and not unrealistic asking price which put some of the other cars on the market to shame.

Agreed. Great price. 

I think its looks fantastic and love the interior with the red highlights (Seatbelts, stripe and stitching).

[Lucky Phil]

Yes I agree with comments above.  This one is on my saved list.  Wish I still travelled to Sydney on a regular basis.  Used to walk past CTS each day on the way to the Sydney office.  I certainly would have popped in to have a closer look at this one.  Price not bad.

https://www.carsales.com.au/cars/details/porsche-911-2018/oag-ad-19124153/?utm_campaign=search-alert&utm_source=notification-center&utm_medium=email&csn_atid=811e628c-4a1b-4596-bebf-7de67ae8cf0a

[Stephen Tinker]

Yes - but damn you have to be seriously wealthy to buy something like this @ $320k + shipping + O/R costs (what is it in Vic, something like 9%) + rego and insurance costs = too rich for the majority of us (which includes me) 😬

[luzzo]

8 minutes ago, Stephen Tinker said:

Yes - but damn you have to be seriously wealthy to buy something like this @ $320k + shipping + O/R costs (what is it in Vic, something like 9%) + rego and insurance costs = too rich for the majority of us (which includes me) 😬

For sure it a lot of cash.  The Vic stamp duty thing is ridiculous. It would be around $30,000 for Stamp and Reg & RWC. 

This GT3 just looks like a good price with this spec, and low kms, compared to the rest of market. (these new would have been ~$400k with options but there is nothing Manual to buy new at the moment 😪)

[sleazius]

2 hours ago, luzzo said:

For sure it a lot of cash.  The Vic stamp duty thing is ridiculous. It would be around $30,000 for Stamp and Reg & RWC. 

This GT3 just looks like a good price with this spec, and low kms, compared to the rest of market. (these new would have been ~$400k with options but there is nothing Manual to buy new at the moment 😪)

This one would have been in the 370-375k mark drive away provided the ad is accurate. Its my car's twin, just with less options. Seems like a decent price.

[NBTBRV8]

I'd say this one has seen a bit of track time.

Check out this 2017 Porsche 911 GT3 991 Auto MY18.

https://www.carsales.com.au/cars/details/2017-porsche-911-gt3-991-auto-my18/OAG-AD-19128546

 

 

[hugh]

I don't understand why you would buy a GT3 if you didn't intend to ever drive at a racetrack. 

[NBTBRV8]

Just now, hugh said:

I don't understand why you would buy a GT3 if you didn't intend to ever drive at a racetrack. 

Not everyone wants a car that has needed a full set of rotors after 13,000kms