KevinMac

I have seen some third party offer the Bi Xenon headlight replacement bulbs with higher temps.

Let's not go there you have no clue what my backround is! You really are just throwing around what you see on the internet, and have no idea how it ties together! Just for your education, firmware is written to meet certain criteria the manufacturer is seeking. So go read some more, and get an education on Software and Digital circuitry developement! Then we can have an intelligent conversation! The sensor will hear more but does not mean it's a cure all. There is more to it then just a listening device! Your previous posts says all that is needed to know you are just arguing for the sake of arguing! BTW the tie to the crank position sensor is a method to try narrow down to what cylinder is pre igniting, therefore allowing individual cylinder control as apposed to introducing broad control. In no way provides any control, it's just a data flow! The ECU will decifier to the appropriate cylinder, and attempt to adjust. Still does not mean that the ECU can accommodate the knock below a paramter that is setup in the firmware. By introducing 87 may be well below the adjustable parameters. Like I said it is how the manufacturer has written it's firmware. You quoted all the tech words out of the glossary of some document but can you tie it together! "ME THINK NOT" Once again am not saying the Porsceh ECU cannot, all I am saying is to many speculative comments are being made without knowing the manufacturers parameters. Nowhere in any of their documentation do they say you can run 87 as other manufactures say you can! So until someone can provide Porsches acceptance of using 87 then there is no need to continue with this! Enough said! This thread needs to be closed!

Actually the current knock sensors are broadband single wire and flat response two wire knock sensors. My response is up to date. If the sensor was responded to for all harmonic frequencies it would never allow the engine to run at it's full potential since engines harmonics are not all due to knock. They still have their specified window! Therefore a base line has to be configured. Once agan a knock snsor is not the cure all! Think this topic is worn out!

rslinger - I do not have any info to say if anything above 93 will net better performance. ihave heard that 100 in higher temop condition works well, but no validation if iti s true. I know if you go too much it will go negative. Think you might want to ask the question on some porsche race sites

KevinMac, I was considering the RE960AS as you said but they are not approved by Porsche. I was trying to stay with what they approved. However, since I have a wide temperature variation to deal with throughout the year I don't think it is feasible to have two sets of wheels and tires. Did you switch to the Bridgestone all around or just on the rears? Have you noticed any difference in handling? My opinion the Porsche approved which has the "N" designation just means that tires meet the design criteria of the Porsche design. This by no means that the tires without the "N" designation could not exceed the performance criteria. I don't think you will suffer in anyway not using "N" designated tires. I can understand if you live in an area that needs an all season recomendation which would dictate an all season high perfomance tire. No I did not go with 4, I still have the Conti's on the front since they still have plenty of tread. After a few months with the Bridgestones on the rear and Conti's on the front and have expierenced no problems in wet dry or handling.

I had the Conti Conta 2's they don't last and get noisey. Carrera's are known for rear wear out quicker than fronts. Withthat said I have gone to a set of Bridgestone Potenza RE960AS Pole Position, which supposedly have 40 K tread wear out guarantee. I can't say at this time since they are to new, that they will make 40K. I can say they out perform the Conti Con 2's, from a handling, noise and ride perspective. So when the Contis are gone take a look at them. Tire rack has very high marks for these.

Such a stubborn, condescending view begs for other opinions. Here's my 2 cents. It doesn't take a "self proclaimed expert" to know that there is fuel in the tank without using a dipstick. The expert can monitor the fuel level gauge and if there is no reason to disbelieve the gauge, he can tell the level from it. Much in the same way, a "self proclaimed expert" can monitor the "combustion profiles" (boy there's a twenty dollar phrase) by monitoring knock sensors and ignition timing "profiles". The knock sensor feedback is quite simply a monitor of "There is detonation" or "There is no detonation". Period. It's quite simple and does not lend itself to any exotic study of thermodynamics, wave theory, or "combustion profiles". I'm sure that your answer will be that I myself am also a self proclaimed expert but in fact I have gleaned this knowledge from schooling and 30 years experience engineering race engine parts and systems. Sorry for the pointed response but your attitude begged for it. Pointed response or not my response was based on the attitude of another! That's interesting, you ever write any mapping firmware! Have you ever developed digital interface of OBDII diagnostics into a technician terminal. Have you ever wriiten or even seen tuning software and remote engine monitoring software? Well I probably know the answer to that, and if you can just say that since you have a knock sensor that is the cure all, you are way off. The limitations of the maps can only go to the a low threshold! So depending on the threshold written into the firmware will be the determing factor. Even if the knock sensor continues to hear it does not mean that detonation will cease! A knock sensor is tuned to listen in the 5khz range. Combustion chamber cylinder bore and temperature are charateristics that vary knock frequencies. Engines typically have muliple vibrations modes. So in reality depending on the condition the design or location of the sensor may not pick up all the knock. It is not unusual for one cylinder to knock and not be detected due to the transfer function of the cylinders and engine characteristics. In addition, the base reference of the sensor has to be set low for knock detectiion above idle speed. There may be times a knock sensor to shut off above 4000rpm make more dependency on the ECU maps to prevent knock in this range. The sensor can actually not pick up 100% of the knock based on variables mentioned. So now add in 87 octane which may or may not cusae issues! Thus my point in my posts. Another point od f which I agree that a knock sensor goes from base to no knock condition, but that means nothing based on the design and other factors mentioned and if the maps cannot correct then it makes no difference if it hears it or not. The Maps are wrtten for fuel economy, emission standards and performance. With all factors considerd. The outcome is a limitation of the stock firmware. As an engineer one would think you know this! Nice try though! Since this all came from someone making a mistake on using the correct octane, the article I referenced in my above posts backs that 87 octane will have it's problems in a Porsche 996. Have a great day!

wwest - think you just like to argue for the sake of an arguement. Your the one that posted low octane in Europe. As I posted their low octane is = to 91 in the US = within spec of the porsche spec! So what's your point! Point me to where does Porsche says regular, all my documents including the maintenance manual says Ron 98 = 93 Ron+Mon. That's what's funny you are all over the place with your comments! Low octane 87 in a twin turbo, that answers it all. Thanks for such a competant answer! Now I know where your knowledge really lies! Your true colors are really showing now! Nice job!

I hope the mods are not the reason you can stay with a GTO, hopefully the GTO you are talking about is the 400HP version, since the published specs are pretty close with the 996 edging the goat out in 0-60. ( based on published #'s after test drives) Anyway be careful with the cold air intakes, some suck in hot air and may cause a lower output. I agree the published numbers adverised by OEM mods is over exagerated.

It cost me about $120 before shipping. Use the collision catalog search boxes. Bought it here: http://www.trademotion.com/partlocator/ind...CFReQGgodj2UgCA It's not a tuff thing to do, everything snaps off just becareful when removing the storage box switch and wire. If the current storage box has the old hinge set, you will also have to buy the hinge kit, not expensive. Use the instuctions to change the shifter out to a short shift kit. It has all you need to remove the console. My only suggestion is when you remove the side cover that encloses the handbrake lever. Wrap the lower section with tape. This will keep it from getting scratched when removing and replacing the console.

Good luck, I searched high and low and could not find a match (graphite grey), wound up buying a new center console, which really was not that much of a wallet hit.

So let me get this straight you are comparing a Mazda CX 7 a passenger crossover vehicle vs a performance car, wow! We are talking Porsche a performace vehicle!. Once again would you really put 87 octane in Carrera turbo "street engine"? Well if you don't know what a performane tune is, which there are many avialable for Porsche, how can you comment on the acceptable fuels to use? Oh btw if I remember correctly most European countries have a minimum or "regular"@ 95 RON which is = to 91 in the US. Kinda matches the octane recommendatin in the owners manual 91 to 93! Funny how that works out! With that said, all I am saying is I would not make any speculation on using 87 unless Porsche says it's okay, or someone has looked at the maps! To just randomly say you can use it is nothing but speculation. Check this out from PCA - looks like what I have been saying. http://www.pca.org/tech/tech_qa_question.a...9-50218293CFDC}

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Okay, question for you, then. With the A/F mixture and ignition timing "mapping software" so easily malable/modified and regular fuel less expensive and such a common thing why wouldn't the parametric mapping ALWAYS allow for the use of regular fuel. What's the harm...?? Wouldn't it take a somewhat idiotic engineering team, engineering management, to overlook such capability..?? Allow an engine, "street" engine, to be damaged as the result of an owners simple oversight/mistake...?? NOT..!! No because they already specified the fuel that should be used! Porsche and other performance cars are fighting the battle between performance and emissions! To just say you can use this fuel and to design with such wide paramaters is a false understanding! It's a myopic view to think it's as easy as your comment! Those who buy these cars are expeced to want the performance, therefore the price of fuel is not a factor. If that is your concen then go buy a honda! With your logic on street engine, then 87 must be okay in a non natually aspirated street engine too? Hey the guy made a mistake and put in the wrong fuel! Go try and get a warranty claim done if it's found out the so called street engine did not use the recommended fuels! BTW when you go get a tune, guess what, they tune to the fuel being used. So turn the question around, if you get a performance tune what makes you think you can step down from the design? It is a bad assumption on your part! So to respond on your comment NOT! Nice try though!

I bow to the self proclaimed experts who know nothing about the mapping software and insist that the scanner watching the sensors tell the combustion profiles! No longer worth the discussion! Do what you like it's your vehicle!

And wouldn't it be somewhat idiotic for Porsche to design a car that didn't have enough parametric mapping range, A/F mixture and/or timing adjustment, for use in a country/region/continent where premium fuel is often not available...?? Your right and premium is not available in all areas, that's why Porsche says you can run 91. Droping 3 points is ususally not an issue, but 6 can be! Sensors are not going to tell you anything other than they are working and depending on the one you have you will see what the outputs are. Will not tell you the combustion profile! You have no clue by looking at a scanner and seeing if the map is at it's lowest limit unless of course it has the map download capabilities. As I said it's all speculation! You have to look at he actual maps! Until someone can provide the actuall map parameters, I would not stand by that 87 can be run without any damage. But then again it's your cars do what you want! With over 11:1 even with low ambient temps the combustion temps are higher. So lets not go that route. Yes i have a scanner.

This is all speculation, anyone without seeing the maps to say the computer will detune to 87 is just making assumptions. I believe it will to 91 but since the recommended is 93, I would not make that assumption! I know for a fact that maps that I was involved with Ford and GM, the threshold was not that robust to allow such a wide margin of error. Yes it will attempt to retard the spark, and adjust the fuel flow, but some maps are not that robust to get you that far below the recommendation. Based on the lower limit of not allowing it to detune that far it can only offset some detonation. BTW on some cars high speed detonation may not even be audible! So unless someone can show the actual fuel map. I would not speculate on anything! So why take a chance!

Hate to tell ya, Porsche does not recommend anything past 18's on a 2000 C2. The suspension is calibrated. Read this: http://www.europeancarweb.com/tech/0505ec_...ires/index.html

No. It will not hurt the car. I disagree, if the computer does not have enough threshold to detune to 87, yes it could hurt the car by detonating. Just the mere fact you are over 11:1 compression ratio, I don't think the maps will accomadate 87. So throw in octane booster and when down to 1/2 tank fill it with 93 and octane and booster again. Do not drive it hard until you can at least get 93 and octane booster in together.

It could be just a bad connector to the coil that is causing you grief!

If that were the case you would have a noisey valve train, and this was not in the post. If the noise is not present, it sounds to me they are just throwing parts at it. Based on the post, I would be very skeptical about the diagnosis.

If the rainfall was really part of the problem, it surely would not be the valves. Maybe the rain and the problem are coincedental, Was a compression check done and if so what were the numbers?. Where there any codes beside #5 missfire. I would get a second opinion!

I checked the receipt and the dealer had put in 15x50 Mobil 1 at last oil change. Was planning to change it after the Summer, but alas, I didn't need to do that. Just needed to mop up a few gallons from the garage floor and then the street once the flatbed wrecker showed up and we pushed it to the street. I will definitely not run that viscosity in the future, as it's not THAT hot here. Sent a PM regarding price (roughly, in the $41k range). Thanks for the good wishes - I'll keep my fingers crossed for a new engine, and will post back once I hear from the dealer. Wow a Porsche dealer put in an oil that was not on the recommended Porsche oil list?

Perry - I agree with you when you compare base number as the temp rises Mobil 1 0w- 40 compared to 5w- 50 has a higher viscosity index number at 100 deg C. The discussion was around Mobil 1. 0w - 40 cSt @ 100º C 14 5w- 50 cSt @ 100º C 17.4

Yes the center console is plastic, and if you want yours painted as Loren said it needs to be preped. The actual paint the factory uses is not really a paint as we know it. It actually is a coating more like a dye type coating. http://www.bumperplugs.com/BPindex.html