dubsiren

Being in Chicago, I see a trip to Momence in my future.

BNB911

WOW me 2!

I also see us spending a boat load of cash.

What do you think the Flat 6 Innovations stage II. Engine goes for ?

PV997

Love yah Groov, but you need to improve your reading comprehension. I was specifically talking about piston coating flaking, not cylinder wall flaking, which I stated several times in my comment. The 9A1 uses a plated coated which doesn't flake, it scratches (which I also said).

Edit: Went back and looked and I stated in my first comment but just sort of alluded to it in the second comment. Have to give you a pass on that one!

PV997

Thanks for commenting Charles.

I've read your white paper previously and don't remember you implicating the piston coating. Curious if you agree with Baz's thoughts regarding Ferroprint (soft sprayed coating on 2001+ M97/98) vs. the harder plated coatings (Ferrostan and Ferrotech (9A1)). Baz seemed to think it was a key contributor in the 996 and 997.1 scoring. I'll borrow one of his photos of some serious Ferroprint pealing since Rennlist won't let him post.

Always ready to learn from your comments. BTW, how do you handle 9A1 scoring since it has a closed deck? Is it a hone and resleeve or something different?

Wayne Smith

I haven't seen any mention of this. Do you have any links to educate me? I have heard that cold seizure is the primary potential failure and this goes back to a few blocks with problems during casting that eventually warp to oval near the base of the closed deck. But flaking is new to me. Thanks in advance for any information you can offer.

PV997

Woah, take a deep breath and step back from the edge. The scoring is not a time bomb, it just eventually fails and when it does you fix it. At least it doesn't do collateral damage like some other potential high performance engine failures. It does suck when it happens to you, but fortunately we got guys like Charles who can fix you right up.

The 9A1 in the 997.2 and 991.1 can also score. But by virtually every account it's at a much lower rate than the 997.1 so we got that going for us, which is nice. I sold my 997.1 with 90k miles and never had a problem. Now I've got a 997.2 Turbo with 50k miles and no problems there either. Both are California cars though, and extreme cold weather does seem to be a factor in the failures.

groovzilla

Wayne I addressed this question another thread and copied/pasted the Posts from various forums regarding the flaking/scratching of cylinder wall coating on the 997.2 engines
. Several 997.2 cylinder wall flaking posts on various Forums as well as some on UK forums that I have read over past year.

dubsiren

We might have different definitions of timebomb, but when I am looking at catastrophic engine failure, yeah, I think timebomb is accurate. A 15-25k repair because of a single scores cylinder? And this coating is wearing out on all of these engines…..

Don’t the Turbo cars have different cylinders and cases?

BNB911

Yes, turbos are different.
What options have you looked at for a replacement Engine LN, Flat 6, local builder?

dubsiren

I got a 21k quote from a local shop for a 4.0L build. An 18k quote for a used engine. LN is my next stop and they are close to me, so hopefully they can help.

BNB911

Yeah, LN is about an hour away from me. I live about 10 mins away from Blackhawk Race track.
From what I have found it looks like LN has very solid kinda "Bone stock type motors build with all the upgrades" For a very solid every day driver car, for low 20's. and they or the shop next to then will do install. (to stock but a very high quality reliable solid build)
Or Flat Six Motorsport's in GA., has several options that go above and beyond the LN option. But I can only mange the cost increase.

what do you have 997.1 or 997.2

Wayne Smith

I read those posts carefully and didn't see anything to substantiate your claims. Sorry, maybe I missed something, but I read it a couple of times.

I have Baz's technical report with pictures and details. This was distributed per a signed NDA agreement and covered the 997.1 primarily with a short section at the end discussing the 9A1. This report implies for the 9A1 the failure mode is cold seizure and only on a few blocks that he feels were destined to failure from the time they were cast. In other places he has stated he was sharing his details with Jake and Charles but I have not been able to find anything beyond that point.

Sorry about drawing this out. I believe it is too easy for all of us to get confused regarding these motors and their failure points. I also feel it's important we try to make sure we're all going down valid paths. I'm still trying to figure out what path that might be for the 997.2 owners. This isn't a battle about who is right and not. Just an attempt to make sure we're not confusing ourselves, me included.

linderpat

As of now, I bought the car with just a tic under 60K on it 4 years ago, and it now has 97K. I drive it as it was intended to be driven, but I take exceptional care of it too. It simply does not use any oil. I rarely have to add any, maybe after a track weekend I'll be down a 1/2 quart, but that's it. I get a Blackstone report at each oil change, and it reads near perfect - within each spec. No lights, no power loss. So right now, I'd say no scoring. Now's the time to sell it I think. These threads are starting to freak me out!

PV997

Best to just get the freak out over with and get passed it, it's like that five stages of grief thing. It is what it is, I view it as an opportunity to do a bulletproof rebuild. My wife would throw a fit if I tore apart a "perfectly good" engine so it takes away that impediment.

PV997

You're thinking of the 996 and 997.1 Turbos which use Nikasil cylinders (that don't score) unlike the NA cars from the same years which use Lokasil (which do score). The LNE replacement cylinders use Nickel-Silicon-Carbide (their version of Nikasil) to replace the Lokasil cylinders.

Both the NA and Turbo 997.2 (and 991.1) use Alusil for a monolithic case/cylinder construction (the 9A1 engine). The Turbo case undergoes additional post-casting heat treatment to stabilize and strengthen it, but it's fundamentally a reinforced version of the same block. It seems to have worked as 997.2 Turbo scoring looks to be pretty rare (anecdotally) though it's not unheard of. Porsche went to the 9A1 engine for the GT cars a few years later with the 991 model.