mgordon18

I'm trying to do a little math here to figure out approximately when Porsche switched to the beefier IMS bearings in the M97. If I can get a bunch of engine numbers along with their corresponding production dates, I can graph it and see if anything makes sense.

So let me know, S owners. I need some data!

Thanks in advance,
- Mike

LO997S

I have a 2006 C2S. Unfortunately, it's at the dealer right now getting a new engine so I can't tell you the engine number. Non-IMS issue, though (cracked cylinder block).

Zeus993

2006 C2S
Build date: 09/05
Engine: M97

mgordon18

I'm actually looking for the full engine number - not just the M96/97 part. All 11 characters (e.g. M97/68509791).

Thanks!
- Mike

ecostellodo

Build date: 10/05
Engine Type M9701
engine number 68606852

pewter82

I think the engine info will be on the DME scan or PPI from a Porsche dealer if you have that paperwork handy for this thread.

fpb111

http://www.6speedonline.com/forums/9...nual-cd-2.html

"The information on the IMS/engine number were extracted from the 2005/06 workshop manual. The info is on page 426. I believe you can still get a copy @ 997 6speedonline. As for manufacture date, there is no way to tell, same as for a VIN."

"To determine if your M97 engine has the improved IMS, you will need to check your engine number.
if the engine number is 68509790 and below, unfortunately it still has the smaller removable IMS bearing.
if the engine number is 68509791 and above, it will have the new large single row IMS. The IMS cover also has the 22mm nut.";

mgordon18

Yes. That's what I'm basing my nerdy calculations on. I'm trying to use that info to determine approximately what month the 68509791 engine was put into a chassis, so I can then use the production date to help me determine IMS status on potential cars I might buy. It's easier to ask a seller for a production date than an engine number. And, in fact, I've been able to figure out a way to eyeball an '06's VIN to match it up with an approximate production date. So, in theory, if this works out, I'll be able to tell from the VIN whether or not an '06S car has the upgraded IMS.

The last 6 digits of the engine number are the most important. Of those last 6 digits, the first is the model year for which the engine was made (5=2005). The remaining 5 digits are the actual serial number of the engine. So the first "S" engine with the upgraded IMS was the 9791st "S" engine built for MY2005.

Wish me luck.

blake

Awesome post Frank - thanks! I just spent and hour searching Rennlist for that info and came up short...

I can add that my '06 Cab S was built "02/06" and has engine #68614009. This would put me in the "above" category...

-Blake

mgordon18

Boy - it's getting late here on the east coast and my mind is becoming mush... It seems I've proven my own case without having to do any of the math I was planning on doing. Decoding the engine number is enough.

If the engine number info is correct (and I have no reason to think it's not), then all 2006 Ss have the upgraded IMSs. And any MY05 engine after 9791 should be fine too.

I was originally under the impression that the "year" digit in the engine number was the year the engine was MADE, not the model year it was made for. But when you look at ecostellodo's info, above, you can see the "6" digit in his 10/05 production car, meaning the year digit must be for model year.

There's been a lot of conflicting info on this board about when the upgrades started. I've read mid-05 and mid-06. I think I'm now on the side of mid-05.

mgordon18

PS - by my calculations, that 9791st MY 2005 M97 engine is probably in an '05 S chassis with a production date in December 04/January 05.

Here's the data -

For MY2006:
Engine # -- Chassis production date
03833 -- 08/2005
06852 -- 10/2005
14009 -- 02/2006
16022 -- 03/2006
16946 -- 03/2006

This equates to approximately 2000 engines/month, or 22,000 engines/year (since they take August off, right?).

So that puts MY2006 engine 00001 (i.e. 68600001) in a June 2005 chassis.

If we assume MY2005 also started in June (of 2004) and also did 2000 engines/month, the 9791st engine (i.e. 68509791) would be about 5 months later + August = December 2004.

I admit this is very seat-of-the-pants, but it seems plausible...

Zeus993

Ok. Understood. Now please tell where I can find the no. Tx.

mgordon18

Hey Zeus, I've never seen one in person, but check out post #3 on this thread:
https://rennlist.com/forums/997-foru...s-bearing.html
Hopefully that'll help.

mgordon18

Edgy - if you're reading this - I'm guessing from your engine number that you have one of the last '06s made. I'm betting that your production date is around May of '06. Am I right?

blake

When I first saw this thread this evening, I searched Rennlist to find the location of the engine number. I came across Edgy's post and then crawled under the car. The engine number can be seen when looking at the engine from ground view behind the rear wheel well on the driver's side. As my car is a DD in a snowy climate, it was covered with grime... I then remembered that my CPO documentation would show the number and sure enough, it was right there on the paperwork...

-B