74goldtarga

Jamie, I appreciate your advice and interest in helping the community. What oil do you prefer for these engines? I am currently changing oil after every track weekend, which might be excessive but can’t hurt.

I personally have gone to shifting manually on track with the PDK at 8500 or so RPM for the reasons you mention.

Jamie@dundonmotorsports

I find it more fun on track shifting manually and always have. But I started tracking with a 997.1 GT3RS manual, so there's a "rhythm" to it I enjoy.

We've used Amsoil for a while now in all of the cars. In the new 992 RS, we will be running the now "mandatory" Mobil One fill as the car is under warranty and don't want any shenanigans from PCNA...

I believe if the car is under warranty it's best to use the new Mobil One until it's not under warranty. So far it appears to be a "good" oil, but haven't dove in to check it out quite yet...

74goldtarga

Which AMSOIL product? AMSOIL is based in Superior Wisconsin and has world-class manufacturing facilities there. I have wanted to stay with an A40 product. I haven't heard of AMSOIL being used in Porsche circles maybe for this reason. One of their engineers recommended the Dominator 10W-40 for track use for my 2014 GT3 but I haven't heard of anyone using a 10W-40 and it doesn't have the A40 certification.

johnsopa

Grenaded as in valve train failure which completely shut down the engine, great ***** of fire coming out the exhaust with oil and coolant mixing and exiting via the exhaust valves.

No case punctures.

Zero warning, no CELs, UOA was fine.

Around 30k miles.

Cay_PI

That one FF is completely eaten away... crazy that it still didn't drop CEL.

Indyxc

@johnsopa Thanks for sharing, wow that is significant wear, and yeah that is grenading the engine. Interesting in the fact that the wear is so significant and did not see a CEL for misfire, and interesting that the finger follower wear caused a valvetrain failure. Any feedback on how a worn finger follower caused that?

DDE997

I would suspect that the FF material is softer than the cam lobes. The RC hardness should be very close on both the cam and FF.
Over my 30 years of engine building, I have seen plenty of many cam failures. One Cam grinder that is no longer with us, had the answers to fix any cam failure problems.

Tom@TPC Racing

Thanks, OP for doing the teardown and sharing the pics. We have not had an opportunity for a .1 GT3 street car engine teardown since they have been in the factory warranty program.

Have not done a .2 GT3 street car engine either for the same reason above. But here's a .2 Cup race engine teardown, which shares the same part number camshafts and followers as the street car engine. Factory 8500rpm rev limiter. Approx 110 hrs.
The lobes show where the highest pressure occurs but not catastrophic.

Cay_PI

Thats more "wear" than the G6 engine above in the thread I think, so they are also not immune. but still fine... 110hrs of track. Thats 15k miles hard use or so... good engines.

No DLC on the camshafts inerestingly...

Indyxc

Agree, those cams look worse than the G6.

So is the 991.2 GT3 Engine the same cams and followers, except the oiling was further improved, and instead of a hydrauilic lifter they used solid lifters?

greggmorton

This is all incredibly helpful and fascinating, but at the same time confusing and hard to make sense of! …or I’m just thick-headed (most likely).

After all of this, I may or may not have a few emails out to dealers on certified 991.2 GT3RSs.

Indyxc

It's a personal decision, based on budget, usage case, level of worry, etc. Really it is the worry of what may or may not happen, depending on mileage and use case. For me, someone who doesn't (won't) track the car, and not drive a lot of miles the cost delta for the .2 GT3 RS (~40k nominally) was not worth it for something that probably won't happen. My plan with that 40K is actually to buy a older manual convertible to cruise with the family.

As Jaime said, for some the inspection of the .1s may not be worth the squeeze. If you are tracking the car constantly, and driving a lot, then by all means a .2 might be better vs. inspecting and replacing. However, any car that is track quite a bit is not going to make it high miles either. As Tom noted the cup car engine was torn down at 110 hours... This is where those who say, look at Cupcar runs Mobil 1 0W40, and fail to mention the constant interval inspeciton / maintiance, etc.

911-140.6

Thanks to the OP for sharing the pics !!!

Also, sorry to see the grenading of JohnSopa's motor...painful to look at, and it's still disheartening to see the range of late G0's and perhaps now G6 motors still having FF issues...there's no reliable or predictable delta on how and when , just that one needs to basically hold their breath.

Regardless , for me I no longer have to worry about this even though I still had about 16 months of warranty on my former 991.1 GT3...yes, I traded it in. It was a brutal day when the shipper picked her up last week but I hope it goes to a good home.

I'll still pop in occasionally to see where things are with the G6 as I can't imagine Porsche AG abandoning you guys. They're all about retention, and how can they foster that if there's a bunch of 991 GT3's hitting the used market broken....or the values being affected by this now fairly known issue.

Cheers everyone !

Mike

johnsopa

To be clear, my grenaded engine was the original and my car is an early 2015 model. It had an F motor so the eventual failure was expected and hoped for sooner rather than later. I purpose looked for a 2015 model with original motor and 20k-30k miles.

I prefer this car to our 2018 GT3 and wish there was also a manual option (besides the R of course) that I could pick up at a “discount”.

Cay_PI

991.2 has the same basic design (Schlepphebel). Neither 991.1 nor 991.2 really use hydraulic lifters as its typical in normal road engines (traditional hydraulic lifters sit inbetween the cams and the cam lobes). 991.2 has a completely solid design without any hydraulic elements. 991.1 has hydraulic elements at the mount of the finger followers - so the position of the finger followers is altered to control clearance. Thats the only difference in the construction.

What we see on the .2 engine shown here is, that there is very high pressure at the point where the cam shafts press on the finger followers. That affects all engines with that design. On the G6 they used the most expensive materails in the end to make it durable, in the .2 they simplified the design instead to reduce pressure / improve oiling. I think G6 and .2 will last very long so nobody needs to worry.