In one of the last couple of Excellence magazines there is a pretty comprehensive article addressing the ongoing support and improvement of our engines in the post-production period. They had a few manufactureres listed who are making "better than OEM" parts and fixes.
I tossed the issue, but if I were you...I would look for the info. maybe someone has the issue lying around.
Wasn't that article about the M96 engine? Don't all Caymans have M97 engines?
I'm curious about the differences between M96 and M97. I've never seen any information on that. I believe the M97 is a minor update to the M96, but I'd still be curious about what they changed. I believe one of the things they addressed was failures of the rear main seal.
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Last, but not least as Beez said, if I had it to do over again I'd put a new DFI motor in instead because it has scavenging pumps in all 4 corners of the heads and a higher output oiling system all around and no more Intermediate Shaft. You get higher rpm range, less moving parts and better oiling vs. the M97 engine. Once you see the rebuild cost, I think for a few thousand more you could go the DFI route and in my opinion would be well worth it. I'd also like someone else to be the DFI swap guinea pig before me.
I think you'd have to go to a new engine management system as well. I believe the DFI motor is using a different system from the M97. Don't know what that would add to the overall cost.
if I had it to do over again I'd put a new DFI motor in instead because it has scavenging pumps in all 4 corners of the heads and a higher output oiling system all around and no more Intermediate Shaft. You get higher rpm range, less moving parts and better oiling vs. the M97 engine.
I totally agree with Ken's comments. But also I'm waiting to see what develops on the M97 engine in the near term as far as problems. Consumer Reports makes a point of NOT buying the first year of a new model. In this case a new engine and trans design. Let the dust settle before you make a more forward, unless you can afford to thrown money away. I can't.
Well I'd say in this instance it isn't really a "new" model, it is simply a refresh/update to the Cayman. Even the engine has been tested for quite some time and has been in production for a year for the 997 line. I don't see any 997's blowing DFI motors from oil starvation or missed shifts or other mystery reasons as of yet. I've also talked to people who have torn down the new DFI engine and without exception each has told me that the engine is much stronger and better designed than the M96 or M97 engine, one person even likened it to the new "small block Chevy" of motors for Porsche that they will use for many years to come.
Lastly, the 2006 Caymans don't have any unique problems that the 2007 or 2008 cars aren't also subject to other than something minor covered under warranty, it isn't like 2006 cars are all lemons. I would have no qualms over buying a 2009 car or a DFI motor. Sure there "could" be some defect in the DFI motors that we don't know about yet but if it hasn't shown up yet I doubt it is catastrophic but rather something small and hopefully easily corrected, there is also the potential of a supplier problem at ANY time, a porous block, a faulty piston, etc. but you are subject to those during any model year, I'm talking more about a systemic problem like a rear main seal leak in the M96 motor or Intermediate Shaft failure in the early M97 motors, etc. Keep in mind that Porsche also fixes these issues under warranty and has been good in the past about extending warranties for known issues like the porous block problem on early Boxsters.
The situation we have here is that when a Cayman is driven hard at the track repeatedly and/or raced there are additional precautions that should be taken with the M97 motor to keep it from having problems. Will all M97 motors have a problem if driven hard? No, will some? Yes. So why not try to prevent them with some add-ons/modifications if you plan to drive your Cayman that way. This really has nothing to do with street driving, someone who drives their M97 Cayman on the street only is not likely to ever face any of these issues.
One thing people seem to miss when they ask "why isn't Porsche racing the Cayman?" is that if you ask Porsche to convert a regular 911 into a race car they'll tell you NO to that as well. Their race program is for a specific variant, the GT3 and after it has had racing modifications applied to it, Porsche doesn't race a regular 911 any more than it races a regular Cayman. Now theroetically you could take a GT3 RSR and take the equipment off of it and gut a street 911 and install the GT3 RSR goodies in it, but you'd probably spend more than if you would have just purchased a GT3 RSR race car from Porsche in the first place (which you can btw). Porsche would have to spend a lot of time and money spinning up a race version of the Cayman and all of the support that goes behind it. Ask Porsche Motorsport to support a Cayman, the answer is No, ask them to support a regular 911, the answer is No. I suspect "some" of that reasoning stems from the fact that they don't believe they can economically support the M96 or M97 motors like they can the old split-case GT1/993 derived motors. I don't think the M96 or M97 were ever designed to be racing engines, I think they were designed back in the 90's to be the first water cooled engines from Porsche and that's what they became.
The new DFI motors in my opinion were designed to replace the M96/M97 line that had grown long in the tooth and had some design problems and could not support where the company wants to go in the future in both economies of scale and durability/flexibility in its engine programs.
Porsche has built a very good car in the Cayman. I think that it is a fantastic car that cannot be beat in its price range. The problem is that the M96/M97 engines have design flaws. These cars can be driven to limits that result in catastrophic engine failures. Porsche knows about all of the limitations of these engines.
Porsche models 356-No. 1, 550, 904, 910, 917, 936, 956, 962-all of them great race cars- were mid-engine cars. It is a proven platform. The Carrera GT was mid-engined! Porsche knows that to race the Cayman would mean the end of racing for the 911 because a properly race prepared Cayman would out perform the 911. They also know that they have enough experience to do this easily. It would not be that expensive. The 911 is the "icon" and Porsche has said many times that they will continue to support their icon.
I think that we all should continue to push Porsche to support the Cayman. Porsche should start by making a club sport version of the Cayman similar to the 964 RS America or the '72/'73 911 RS. A light-weight no BS car. If they did, I think that there would be lines at dealerships of people wanting to buy such a car.
Does the 3.8 X51 have these same issues with RMS, IMS, oil starvation or anything else?
Point being, if out of warranty, would a X51 swap negate these issues?
Originally Posted by Krokodil
Excellent question. If you are correct, this would make sense, except that my class rules prohibit the swap.
The 3.8 X-51 motors from the 997.1 series of cars are still M97-based, and have the intermediate shafts and can be prone to oil starvation, and oil ingestion, although this is less apt to happen when the motors are installed backwards in a 911. When turned around in a Boxster/Cayman application, these maladies are much more prone. As far as the RMS is concerned, between the use of new and better gaskets/seals, and much better quality control in the casting and fitting of the crankshaft cradles, this is really no longer much of an issue with the advent of the M97 motors.
Krok - Will the transplant of a 3.4L DFI motor as used in the new CS bump you out of class?
[QUOTE=K-Man S;335014] "The situation we have here is that when a Cayman is driven hard at the track repeatedly and/or raced there are additional precautions that should be taken with the M97 motor to keep it from having problems. Will all M97 motors have a problem if driven hard? No, will some? Yes. So why not try to prevent them with some add-ons/modifications if you plan to drive your Cayman that way. This really has nothing to do with street driving, someone who drives their M97 Cayman on the street only is not likely to ever face any of these issues."
I believe that Krokodil took every step available to him to protect his engine, short of a true dry sump system (or accusump).
Krokodil had installed an oil sump extension with the windage tray, the motorsports oil separator, third center cooling radiator, power steering pump cooler, etc.
What else could yo do to protect your engine on the track?
Is there a larger capacity oil pump available? Do you have more details on the Italian "accusump" mentioned early?
I am a rookie and don't even drive my car as hard (as fast..) as Korkodil does but the idea of something like this hapening at the track somehow takes away the fun factor
We all know that racing engines are regularly rebuilt. I don't know how to convert mileage to hours on a race track, but it may be that Krokodil's car with 5,000 track miles on it was ready for, or past, a rebuild. There are many stories of racing engine failures during events. Porsche has had more than its share of LeMans engine failures along with their many victories. Read the Hurley Haywood article in the latest Panorama-they nursed home what was a blown engine for a victory!!
In my youth in good old Nebraska, we were all farm boys street racing our Chevys on Saturday night. I can tell you that you don't want to miss a shift at 8500 in a small block Chevy V8. We found connecting rods laying in a corn field. But we knew that this might happen and it never stopped us from gasing up the car and going out as soon as our chores were done.
So gas up your Cayman and head on out to where you go for your kicks. Just remember that sooner or later you will be picking up parts and needing some quality time back in your garage.
There is no way that an engine is going to last the life of the car if you track/ race the car regularly. Krok got over 5000 miles of the hardest driving possible on his M97 engine, along with many thousands more in normal driving. I agree that we should pool our knowledge and information to see what is possible, and at what expense, in hoping to extend these engine's lives for thousands of more track/racing miles. But at the same time its hard to see +5000 track/race miles from a "non-race" engine as being a huge failure of reasonable expectations.
Our path forward is not yet clear. We can install an OEM remanufactured engine, buy a local used engine, our more than likely rebuild the existing engine (if possible) with stronger parts (Carrillo rods, etc).
How about forged aluminum pistons, Nikasil sleeved block, a stroker crank, and H-beam connecting rods?...and maybe a turbo to boot?
Didn't you try out the Accusump system? I agree with Gilles above that he did everything he could to avoid problems short of a stouter oil pump or some other oiling system to prevent starvation or low oil pressure (may have been the latter). Perhaps he can make the argument that the only way to "fix" the M97 motor is to replace it with the DFI A91 motor and still remain in class.
If anybody wonders if the 3.8 X51 engine from oil starvation as well...don't wonder any more... I just blew mine in my 987 Boxster S ... .
The worse thing is that from what I am reading in the forum there is not much you can do to prevent it unless you decide to drive it less harder.. .
I am so disappointed. You know why? Not because I will pay for a brand new 3.8 X51 engine, no, although tehe money is quite a lot (11.000euro). I am mostly disappointed because I do not know if I can press the car and I am afraid it will break again if I start pressing it.
You know I was dreaming that I would be able to drive my car to the track at least 6 times per year, fit my slick tires and race like all hell brakes loose...but I see noς I cannot do, I cannot even press it on the road. I had never tracked my car and I blew the engine on the road, just the way you are talking about on your caymans, the last bearing got damaged and then the whole engine blew.
I, as well many others from you, have paid a lot of money to build my car, not only the engine, but the suspencion as well, the brakes, tarrett gudgets, many many dollars have been spent to grand ourselves with a little smile.. it is funny how sad you feel when you realise that all the money you spent, all the money you will be spending, will be worthless and will not solve the problem.. . I just wish I had done more searching before I spent 40.000euro on my car. Now it is too late, I must, like all of us, use counter measures, like the tank extencion or an oil pump to feed the oil on the other chamber under load, in order to try to overcome a problem, which sadly cannot be cured.
I am so f....depressed right now..(bear in mind I broke my engine 15 hours ago...).
Last edited by mpowersurf; 02-13-2009 at 06:18 PM.