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Ok, this is slightly confusing: DOT 5.0 is a silicone based fluid which is NOT used in racing vehicles. It is incompatible with normal braking systems and you can NOT use it. DOT 5.1 is similar in properties to DOT 4.0 and it is sometimes used in racing vehicles. It is NOT silicone based, it is COMPATIBLE with DOT 4.0 and INCOMPATIBLE with DOT 5.0 So DOT 4.0 and DOT 5.1 are compatible. The main difference between DOT 4.0 and DOT 5.1 is the higher boiling point and a different viscosity of DOT 5.1, which is necessary in some ABS systems. Your car does not need the lower viscosity of DOT 5.1 but the higher boiling point is useful. I would therefore use a DOT 4.0 fluid with increased boiling point, such as ATE Racing Blue or ATE Typ 200 (same fluid, just one is blue and one gold in colour). Cheers, Uwe

Hi, Ad 1): For Tiptronic engines, the factory recommended way is take the engine out. Otherwise, it gets very fiddly: You have to take the camshafts out, then you have to pressurise the cylinder so that the valve doesn't fall into the cylinder when working on it, later you have to re-set the timing, apparently that's all much easier if you take the engine out. Ad 2): I agree, I wouldn't change the other springs. Cheers, Uwe

Hi Paul, I've just made some enquiries and contrary to what I've said before it is apparently standard practice to take out the engine for this kind of work. Cheers, Uwe

They must have done. Otherwise how would they have tested compression in cylinder #4? Cheers, Uwe

If you've got no compression on #4, there is likely to be a mechanical problem. If you pressure test the cylinder with compressed air, you can get an idea where the pressure escapes (i.e. intake valves, outlet valves, crankcase, cylinder head gasket). What I don't understand is why they want to pull the motor. If you suspect a defective valve, you can just take off the cam cover and have a look. Cheers, Uwe

From memory: The fans work on low speed: Always when the AC is switched on or if the coolant temperature is >100 Celsius The fans switch to high speed: If the coolant temperature is >105 Celsius Cheers, Uwe

Absolutely. You'd wreck the engine pretty quickly. However, the oil pickups are pretty much at the lowest point of the oil pan, much lower then the pickup for the oil level gauge. So they are never starved of oil. If you hung up your car by its nose from a crane and started the engine, you'd definitely wreck it pretty quickly. However, on roads it's impossible due to the position of the pick-ups. The problem you mention is an issue in off-road vehicles and off-road bikes, because they are operated at much more severe angles of incline. Or of course in racing cars at extreme cornering speeds. Incidentally, I'd be interested to know they solve the problem on planes, because I supposed on aerobatics planes the engine has to be able to operate upside-down. Cheers, Uwe

It is far preferable to use the same brand and type of oil. Porsche says: "Miscibility The engine oils approved by Porsche can be mixed to the extent that it is not necessary to flush the engine when the oil is changed, or another type of oil is used. This holds true for mineral oils and synthetic oils. However, since every brand of oil has a specifically adapted unique composition, the same oil should be used for any topping up that might be necessary between change intervals, whenever possible." Basically, if you mix two oils the oil manufacturers have to make sure that the resulting mixture does not turn into some sticky goo. However, each band has its own additive package, and for optimum performance they should not be mixed. Incidentally, this even true within a brand. For instance, Castrol has hydrocrack (group III) based "synthetic" oils and Polyalphaolefine (group IV) based "synthetic" oils. My understanding is that the PAO-based oils use a different additive package, so for best performance the two should not be mixed. Cheers, Uwe

If the impact was bad enough for the rollbar to deploy, I'd definitely have the tracking checked. Cheers, Uwe

I'd agree. 996 alignment is a lot quicker than 993 alignment, because you can't adjust wheel load and kinematic toe-in. Cheers, Uwe

Hi, I spoke to Nico Strosek today who manufactures these covers. Basically, there is a chance that your covers can be taken off and re-used (easier on a pre-facelift model like yours), but as "Tom Sch" already said, there are some issues. Apparently warming up the headlights doesn't help an awful lot. The idea is to take some kind of flat spatula (preferably non-metal non-scratch) and very carefully go all around the two holes and prise off the cover bit by bit. It should be possible to take off the cover without damaging it, but it is a risky procedure. The main issue is removing the glue from the headlight. Since the headlights are made of plastic and not glass, you are very restricted as to the type of fluid you can use as not to permanently damage the headlight. I seem to recall he reckoned that Methylated spirit would be OK, but I'd certainly try it in an unconspicous place first. Anything more aggressive I'd definitely not use. Apparently it takes an evening just to get the glue off the headlights. Cheers, Uwe

Nice pics. Just to avoid possible confusion: Technically speaking, you are looking at the rear of the engine, that's why it's called the RMS "Rear Main Seal". ;) The clutch-side of an engine is always called the rear, it's just that in a 996 it's mounted the wrong way round. Cheers, Uwe

No, on a LOKASIL or NIKASIL coated cylinder there is no measurable wear during break-in. It certainly does not make it oblong. If it did, you'd have a major problem, because NIKASIL coatings are only around 0.05mm thick. In fact, the whole idea of using a silicon-based coating is to make sure it is harder than the piston ring, so it is the piston ring that wears. Cheers, Uwe

OK, it might be useful to shed some light on the technical background of break-in: As most people correctly understand, the main objective of engine break-in (as opposed to breaking in the gearbox, brakes, and so forth) is making sure that the piston rings fully seal all around the bore. In a 996 engine, there are 3 rings per cylinder: 1) The top one is called a compression ring and seals against the combustion pressure. 2) The secondary compression ring seals against the combustion pressure but also serves as an oil scraper ring. It has a different shape from the top ring and is slightly tapered (1/2 - 1 degree). It also works by slightly twisting. 3) The oil control ring performs the bulk of the oil retainment. It has a completely different design with typically two rails and a spacer. The oil control ring performs its sealing function solely because of it spring tension, i.e. the pressure with which it is pressed against the cylinder wall. The top two rings are aided by the combustion pressure, which gets behind the rings and presses them against the bore. It is because of this pressure that the compression rings seal. If there is insufficient combustion pressure, the top two rings are not pressed against the cylinder wall and break-in takes a long time. This is why cruising down the highway in 6th gear at 60 mph to break in the engine is not such a good idea. Great, so I’m gonna take it to the redline straight away! Err … no. The problem is that high revs mean a lot of heat and high piston temperature, because per unit of time you have many combustions. The main way the piston sheds this heat is via its piston rings to the cylinder, because the rest of the piston is not in contact with the bore. During break-in, the piston rings are not fully seated against the bore and this makes the heat transfer from the piston to the actual cylinder much harder. Therefore, the piston can overheat, and piston rings can get stuck in the piston grooves. Not so good. Also, high revs don’t mean high combustion pressure! Combustion pressure is highest where the engine has its maximum torque (around 4500rpm), and not its maximum power. Therefore, going over 4500rpm does not improve the bedding-in process of the piston rings, all it does is increase the heat (and temperature) because of the increased number of combustions per minute. This is precisely why car manufacturers recommend varying revs and engine load during break-in: You want some load on the engine to assist break-in, but you don’t want high revs for a longer period of time, because of the heat transfer issue. Finally, because of its different design, seating of the oil control ring is not aided by combustion pressure and engine load. It just takes time. Yes, I used to work as an automotive engineer for Mercedes-Benz. I’ve got a B.Sc. and an M.Sc. in Mechanical Engineering from the University of Stuttgart and a PhD from Cambridge. ;) Cheers, Uwe

It has to be said, however, that the apparent technical knowledge of tyre technology of the people volunteering their views so far (with the notable exception of Loren and Toolpants, of course) barely extends beyond "something black and round". Consequently, I'm not sure what information you are able to derive from their views. Cheers Uwe

Sorry, such a comment is totally unacceptable given the price and supposed quality of the car and should never be made to a customer. I'd escalate this to PCA, naming the dealer and foreman. Don't worry about TSBs and the like. You're a customer who paid a lot of money and you can expect a rattle-free car. How they do it is their business. Cheers, Uwe

For engine oils the offical manufacturer information is 3-5 years, provided - the container is unopened - it is kept at room temperature - it is not exposed to sunlight. Opened containers should be used within 6 months. That's the official information. How much the oil really deteriorates if you keep it longer is anyone's guess. Cheers, Uwe

I've got no idea. Maybe they have different emissions regulations down under. So you're right, there seem to be 2003 versions (2.7 or 3.2) without a starter cat. Hang on, he's got red calipers. Unless they are aftermarket, wouldn't that make it a Boxster S? And doesn't the exhaust look like a twin exhaust? I'm lost. :unsure: Uwe

Certainly German 2.7 and 3.2 liter engines have the cat there. It's not the main cat, it's just a starter cat they need because the main cat is too far away and doesn't heat up quickly enough. Incidentally, just called up AFN, London's largest Porsche dealer. They say their 2.7 Boxsters have the exhaust manifold with number 996.111.101.05, which according to my PET is the one with the starter cat. I'd say they've sent you a 2.5l engine. Or they've put the wrong manifold on a 2.7l engine. These things happen. Cheers, Uwe

Interesting. I'm sure they know what their manifolds look like. ;) Anyway, I'll have a look next time I see one in a showroom. Won't do it in the street, otherwise my wife thinks I've completely lost my marbles. Cheers, Uwe

Are you sure about that? I think the European 2.7l and 3.2l engines do have the cat on the exhaust manifold, just like on your second picture. That's the m96.21/22 exhaust. AFAIK only the old 2.5l engine had the manifold shown on the first picture. This m96.20 manifold didn't have the cat on it, because it was the same as on the m96.01 carrera engine. Cheers, Uwe

That's an M96.20 manifold for a 2.5l engine. A 2003 Boxster would have a 2.7l engine and an M96.21/22 manifold. So they sent him a 2.5l engine instead of a 2.7? :clapping: :clapping: :clapping: Cheers, Uwe

I'm glad you got it sorted out. :cheers:

There is also a 9-page TSB "Noises in the Trim Panel Area" that deals with this stuff in quite a bit of detail. Cheers, Uwe

I'd just stick some felt tape (comes in 15 and 25mm width from Porsche) on the surface where is touches. I must have used about half a mile of felt tape in my car, but now it's quiet. Cheers, Uwe