What did you do to your 996TT Today?

User avatar
b3freak
OG (First 100 Outposters!)
Posts: 1678
Joined: Sun Jan 07, 2018 11:46 am
Location: Gawga DAWG Country

Re: What did you do to your 996TT Today?

Post by b3freak » Tue Sep 15, 2020 10:44 am

32wildbilly wrote: Tue Sep 15, 2020 10:22 am
b3freak wrote: Tue Sep 15, 2020 10:17 am

100K miles??? hahahaha! You crack me up dude! You know what I mean.

Might be good to start your "keep my Turbro alive" fund started. ;)
Yeah those Turbro guys have money they don't know what to do with so a new engine block shouldn't be an issue...
Yea, this guy's car is bankrupt unless he can find a suitable core someplace. As Jake has told me multiple times, when an engine like this goes boom, it bankrupts the whole car for most owners. In other words, the cost of putting a new engine in the car will exceed replacement. This is not unique to 996/997.1 Carrera owners. The worst is the Boxsters. Can you imagine? You can find 986 Boxsters all day long for under $10K. But the M96 engine in the Boxsters are basically the same in regards to costs to rebuild. Different displacement/ancillaries, but at the heart, it's still a Porsche M9X engine.

User avatar
32wildbilly
Schnelly is the son I wish I didn't have
Posts: 9751
Joined: Sat Jan 06, 2018 2:46 pm
Location: Kneebraska

Re: What did you do to your 996TT Today?

Post by 32wildbilly » Tue Sep 15, 2020 11:46 am

b3freak wrote: Tue Sep 15, 2020 10:44 am
32wildbilly wrote: Tue Sep 15, 2020 10:22 am
Yeah those Turbro guys have money they don't know what to do with so a new engine block shouldn't be an issue...
Yea, this guy's car is bankrupt unless he can find a suitable core someplace. As Jake has told me multiple times, when an engine like this goes boom, it bankrupts the whole car for most owners. In other words, the cost of putting a new engine in the car will exceed replacement. This is not unique to 996/997.1 Carrera owners. The worst is the Boxsters. Can you imagine? You can find 986 Boxsters all day long for under $10K. But the M96 engine in the Boxsters are basically the same in regards to costs to rebuild. Different displacement/ancillaries, but at the heart, it's still a Porsche M9X engine.
The price to play is sometimes very high.
Get the Shots
Wear a mask indoors because it is still here


I'm 71 years old half blind with a brain addled by excess alcohol for over 38 years in addition to being damaged by 35 years of stress working in senior management for a major RR and have never raced anything on asphalt much less a turbocharged over horse-powered Civic with a boi racer wing hung on the trunk lid.

theprf
NG (Second 100 Outposters!)
Posts: 264
Joined: Thu Jun 07, 2018 9:33 am
Location: Central Mass

Re: What did you do to your 996TT Today?

Post by theprf » Wed Sep 16, 2020 7:22 am

b3freak wrote: Tue Sep 15, 2020 9:06 am Just stay on top of preventive maintenance on these cars my friend. Many buyers jump on these 996/997 Turbo cars because they think the Mezger engines are bullet proof and never fail, etc. But, these cars are a lot more expensive service and Jake says its hard to find a core in many cases when the engine goes boom. This is becoming a more regular occurance at Flat 6. (see attached image) This one came in this morning.
I don't really agree with this, the Mezger designed engine is quite bulletproof if run within its limits. Once those limits are exceeded then it can go bad quickly. It's really easy to bolt on stuff to up the power to 600-700 hp and without supporting mods the engine goes boom. This character with a hole in the block likely bent a conrod because of excessive boost or detonation or a fueling glitch or a missing vacuum line or some other problem due to a canned tune. Since the car was new to him he probably had no idea.
There are a lot of well known engine builders who can extract over 1000 HP from these engines - but it aint cheap and you're not getting there reliably by bolting on ebay parts.
If kept within 450-500 hp with a reputable tuner's tune it ought to be perfectly reliable. It's just so easy to bolt on a set of TiAL Alpha turbos and have 700 hp....

I don't really agree that these engines are a lot more expensive to service, either. You can actually get service parts like undersize bearing shells if the crank needs to be ground. There are lots of shops that can do excellent rebuilds if the engine just needs a "standard" rebuild. It's essentially like rebuilding a 993 or 964 engine with some complications due to the variable cam timing. Of course once you punch a hole in the crankcase you're sort-of screwed, so that can be much more expensive. Used engines (for 996, not sure about 997) are available for under $10k if it goes that far.

That doesn't mean that you shouldn't be proactive with service intervals and keep things in good shape. It is a 20 year old German supercar after all. There are a huge number of coolant hoses on the engine, most of which you cannot get to without removing the engine. That's not a particularly good design. And we have those pesky glued in coolant fittings. And all those vacuum hoses that can come adrift.

I have not the slightest hesitation in driving my 180k mile Turbo on the track, I have done so, and I'll continue to do so. I will keep the power within 20% of stock, I will use good oil, I will keep up with preventative maintenance, and I will rebuild the engine when it needs it. And I will drive it conservatively on the street - I get my fast driving experience on the track.

User avatar
FRUNKenstein
Curator Extraordinaire
Posts: 4193
Joined: Fri Jan 05, 2018 11:02 pm
Location: Wheat field, dammit, wheat!
Contact:

Re: What did you do to your 996TT Today?

Post by FRUNKenstein » Wed Sep 16, 2020 7:45 pm

All good points by everyone. Correct me if I am wrong, but I believe the 997.1 Mezger turbo engine has a camshaft pin that can shear and cause catastrophic failure. The 996tt Mezger does not have that design flaw.
www.kansascityautomuseum.com
Current:
2002 996TT X50, Guards Red
1987 928S4, Guards Red
1987 951, Guards Red
1973 914 2.0 Bahia Red

2006 955S, Lapis Blue
Other toys:
1988 BMW 325i Cabriolet, Alpin Weiss
1987 Bertone X1/9, Verde Chiaro
Gone but not forgotten: 1999 996 C4 Aerokit Black; 1990 964 C2 Guards Red; 2006 955S Arctic Silver; 1975 914 2.0, Laguna Blue

theprf
NG (Second 100 Outposters!)
Posts: 264
Joined: Thu Jun 07, 2018 9:33 am
Location: Central Mass

Re: What did you do to your 996TT Today?

Post by theprf » Thu Sep 17, 2020 7:46 am

FRUNKenstein wrote: Wed Sep 16, 2020 7:45 pm All good points by everyone. Correct me if I am wrong, but I believe the 997.1 Mezger turbo engine has a camshaft pin that can shear and cause catastrophic failure. The 996tt Mezger does not have that design flaw.
The 6TT engine doesn't seem to have this issue, although it seems the 2001 model cars can have the intake cam sprocket (the one with variable valve timing) "drift" a bit, just enough to throw cam deviation codes. My 2001 does this... it's about 3 degrees off spec. I will have to retime the cams this winter when I drop the engine to fix the RMS. Three degrees is not enough to crash the valves into the pistons. The 2001's can also have oddball problems with the intake cam timing adjuster sealing rings - there are three small rings that divert oil flow to adjust the cam to either 0 or 30 degrees of advance, and if these rings wear down the cam advance stops working. The 6TT has an all-or-nothing intake cam timing adjuster - it's either 0 or 30, nothing in between. This is the same cam adjustment concept as used on the VW engines of the same timeframe, like the 3.2 liter VR6.

The 997.1TT Mezger has the intake camshaft gears held by a friction fit, there is no pin. It uses a diamond plated washer to add friction between the cam gear and the camshaft. Evidently the solution for cam sprocket slipping is to add a pin to positively locate the cam sprocket.
At least that's my understanding; I don't have a 997.1TT. One of my friends does and that's what he told me, so take it for what it's worth. This is probably because the 997.1TT has a variable intake cam advance, it can be anywhere between 0 and 30 degrees. This also matches VW engines of the timeframe.

997.2TT's don't use the Mezger engine any more. Rather a shame, I think.

I've also heard that under very extreme conditions that one of the gears on the intermediate shaft can slip disrupting cam timing, only on race engines it seems. The solution for that is either laser weld the gear to the intermediate shaft or use the 959 intermediate shaft that has a one-piece gear. I don't believe this would be a problem for any street or even track car, more of an all-out race car problem.

User avatar
Dr_Strangelove
Won't stay Banned
Posts: 1853
Joined: Wed Jan 17, 2018 2:46 pm
Location: Henderson, NV

Re: What did you do to your 996TT Today?

Post by Dr_Strangelove » Thu Sep 17, 2020 10:55 am

The things we do for these damn cars! My heart really goes out to the guy with the 997.2TT. Talk about "when dreams become nightmares."

Also, 2x :lol: to Frunky. You really are funny. Putting oil in a Turbo? Everyone knows Porsh Turbos are electric.
2003 Carrera: Dark Teal Metallic

User avatar
FRUNKenstein
Curator Extraordinaire
Posts: 4193
Joined: Fri Jan 05, 2018 11:02 pm
Location: Wheat field, dammit, wheat!
Contact:

Re: What did you do to your 996TT Today?

Post by FRUNKenstein » Fri Sep 18, 2020 7:58 am

theprf wrote: Thu Sep 17, 2020 7:46 am
FRUNKenstein wrote: Wed Sep 16, 2020 7:45 pm All good points by everyone. Correct me if I am wrong, but I believe the 997.1 Mezger turbo engine has a camshaft pin that can shear and cause catastrophic failure. The 996tt Mezger does not have that design flaw.
The 6TT engine doesn't seem to have this issue, although it seems the 2001 model cars can have the intake cam sprocket (the one with variable valve timing) "drift" a bit, just enough to throw cam deviation codes. My 2001 does this... it's about 3 degrees off spec. I will have to retime the cams this winter when I drop the engine to fix the RMS. Three degrees is not enough to crash the valves into the pistons. The 2001's can also have oddball problems with the intake cam timing adjuster sealing rings - there are three small rings that divert oil flow to adjust the cam to either 0 or 30 degrees of advance, and if these rings wear down the cam advance stops working. The 6TT has an all-or-nothing intake cam timing adjuster - it's either 0 or 30, nothing in between. This is the same cam adjustment concept as used on the VW engines of the same timeframe, like the 3.2 liter VR6.

The 997.1TT Mezger has the intake camshaft gears held by a friction fit, there is no pin. It uses a diamond plated washer to add friction between the cam gear and the camshaft. Evidently the solution for cam sprocket slipping is to add a pin to positively locate the cam sprocket.
At least that's my understanding; I don't have a 997.1TT. One of my friends does and that's what he told me, so take it for what it's worth. This is probably because the 997.1TT has a variable intake cam advance, it can be anywhere between 0 and 30 degrees. This also matches VW engines of the timeframe.

997.2TT's don't use the Mezger engine any more. Rather a shame, I think.

I've also heard that under very extreme conditions that one of the gears on the intermediate shaft can slip disrupting cam timing, only on race engines it seems. The solution for that is either laser weld the gear to the intermediate shaft or use the 959 intermediate shaft that has a one-piece gear. I don't believe this would be a problem for any street or even track car, more of an all-out race car problem.
Good info. I learned a lot today!
www.kansascityautomuseum.com
Current:
2002 996TT X50, Guards Red
1987 928S4, Guards Red
1987 951, Guards Red
1973 914 2.0 Bahia Red

2006 955S, Lapis Blue
Other toys:
1988 BMW 325i Cabriolet, Alpin Weiss
1987 Bertone X1/9, Verde Chiaro
Gone but not forgotten: 1999 996 C4 Aerokit Black; 1990 964 C2 Guards Red; 2006 955S Arctic Silver; 1975 914 2.0, Laguna Blue

User avatar
FRUNKenstein
Curator Extraordinaire
Posts: 4193
Joined: Fri Jan 05, 2018 11:02 pm
Location: Wheat field, dammit, wheat!
Contact:

Re: What did you do to your 996TT Today?

Post by FRUNKenstein » Fri Sep 18, 2020 7:59 am

Dr_Strangelove (whew!) wrote: Thu Sep 17, 2020 10:55 am The things we do for these damn cars! My heart really goes out to the guy with the 997.2TT. Talk about "when dreams become nightmares."

Also, 2x :lol: to Frunky. You really are funny. Putting oil in a Turbo? Everyone knows Porsh Turbos are electric.
Ha, definitely true, especially those electric "Turbo S" models. I pity the fool that has to settle for a mere Taycan Turbo.
www.kansascityautomuseum.com
Current:
2002 996TT X50, Guards Red
1987 928S4, Guards Red
1987 951, Guards Red
1973 914 2.0 Bahia Red

2006 955S, Lapis Blue
Other toys:
1988 BMW 325i Cabriolet, Alpin Weiss
1987 Bertone X1/9, Verde Chiaro
Gone but not forgotten: 1999 996 C4 Aerokit Black; 1990 964 C2 Guards Red; 2006 955S Arctic Silver; 1975 914 2.0, Laguna Blue

User avatar
2fcknfst
Posts: 6
Joined: Thu Jul 30, 2020 11:27 am
Location: Vancouver

Re: What did you do to your 996TT Today?

Post by 2fcknfst » Fri Apr 23, 2021 9:42 am

Am chasing another !@#$%^&! boost leak...

Post Reply