JFP in PA

There seems to be some significant misconceptions on how this works. The stat does control the minimum operation temp of the engine by controlling when full coolant flow commences (the OEM stat begins to open at 185-187F, but is not fully open until around 200F; the 160 stat begins to open at 160F and is fully open by around 170F or so), but it also controls the minimum temperature the system can return to by "throttling" the flow if the system tries to overcool (this happens most obviously in the winter, but also occurs at warmer temps as well were it controls the temperature to which the coolant will return to after becoming hotter due to being stuck in traffic, etc. ). The basic cooling system in M96 equipped cars has more heat transfer capacity (coolant to the ambient air) than the car actually needs; other wise the car would not cool back down after being stuck in traffic, or when the fans kick in. If the radiators controlled the minimum operating temperature of the system, there would simply be no need for any type of thermostatic control. The addition of a third radiator aid in the rate at which this cooling takes place by adding more capacity, but there is already more than enough capacity built into the car without the third radiator to accomplish it, albeit over a longer period of time. In a race car, because of the uneven demands being placed upon the engine and cooling systems, cooling rates are as critical as total capacity. On street cars using the LN stat, those with two radiators took longer to cool back down than those with the third unit, but both cooled back to the same baseline temps in the mid to upper 170's, while OEM stat cars came back to a 205-210 baseline. This is the "throttling" effect of the stat……

I was hoping you would pipe JPF, What's the exspensive fix? a reflash. This nags me, if an engine is running a 16o stat from the get go, I get can picture it. Hpwever, if a motor that has broken in at 219f for 50k ( worn to fit do a degree) is'nt dropping the temp 50 degrees all the sudden going to change all the tolerances due to a new coeifient of exspansion value. resulting in a refit of all internal components( I.E wear)? I suppose you have had the oil anayze before and after a "stat" change on a high-ish milage motor? Regards, PK To respond to your first question, the expensive fix would have been to re-engineer the engine, with 'minor' upgrades such as DFI, etc. Problem is that once all the tooling and casting molds were done, no OEM is going to throw them away and start over if an easier but potentially compromising solution is available, like keeping the engine running way to hot....... Unfortunately, in the large scale production world, bean counters will always trump the engineers. Yes, we have virgin oil analysis, UoA with the OEM stat, and UoA with the LN stat on the same brand and weight of oil and mileage used for multiple cars that began the sequence with more than 50 or 60,000 miles on them; and we have parallel data on low mileage cars as well. The oil definitely benefits from the lower coolant temps. None of the cars has demonstrated any issues (e.g.: increased oil consumption, etc.) as the result of the change. An interesting, but not fully documented change was that most owners noticed a small, but consistent improvement in gas mileage.

It appears to be silicone, but as I said, just about any lubricant will work as it is only used to help keep the o-rings in place while replacing the tubes. In a pinch, we have used use motor oil and have never had a problem. Warming the engine helps get stuck tubes out if they are really balky.......usually, they just pop right out.

Mike, those are for the outer panels, not the battery cover. The quarter turn plastic ones are a dealer item.

The dash temp display is nearly a bad joke; it is both non linear and grossly inaccurate as well. Most M96's showing around 180F on the dash are actually running 205-210F. LN has the only ones available in North America to my knowledge............

As will any OBDII scanner with PID capture capability (Actron, etc.)..............

The grease is just to protect the o-rings while the tube is being reinstalled. In reality, just about any lubricant will work. Unless the tube is damaged, all you need is new o-rings. To pull the tubes, Porsche makes a ridiculously expensive tool, or you can use a $1 expanding one inch (2.54cm) transom plug that you can find a any boat yard............ Works like a charm.......

Under EPA rules, Porsche has to build a car that will continue to pass emissions standards (those in place at the time of construction) for at least 80,000 miles. Raising the coolant temps has been a cheap band-aid in this effort since the late 1960's, and is practiced by just about all the OEM's. Interestingly, Porsche does not use 185F stats in their most performance oriented engines; the GT2 and GT3's for example use a lower temp stat to maximize engine output and longevity. Dyno tests on an M96 before and after showed that the engine picked up a small, but measurable amount of HP and torque by using the lower temp stat (actual data was published on LN Engineering's website). As for emissions, were I live you can be subject to either "advanced" testing (I/M Readiness via the OBD II port), or a sniffer, depending upon the location. I have several customers running the 160F stat in M96 variants, some for a long time, and all continue to regularly pass emissions testing. The DME's in these cars are more than flexible enough to adapt to the engine running cooler. Perhaps of more interest is that cars with the 160 stat (and have oil temp readouts) also show lower oil temperatures, often 25-30F cooler, which is a big advantage. Comparisons of UoA's on the same M96 before and after switching to the 160F stat show the oil holds up better, as you would expect from the significant drop the oil's running temps. After monitoring several cars for a couple of years, I see no downsides to the 160F stat………..

Yes, I changed my serp belt myself at 62K . I might just do the waterpump and serp belt again while I'm at it. Anybody have any thoughts on changing the waterpump with 82,000 miles as preventative maintenance? Two thoughts: The pump isn't known to be a "survivor", and typically fails with little or no warning. Secondly, you will need to drain, refill and bleed the system a second time if the pump dies next week...........

The 160F stat is an excellent mod for any state; out here we see temps ranging from 0F to 105F, and the unit is just fine. And, yes, the car will pass emissions.............

There should be no flush needed, but you will need a new o-ring for the coolant drain plug (fifty cent item) and a dab of anti seize to put on the plug threads before you re torque it. Check the condition of your water pump; you will need to drain the system all over again if it craps out 5 min. after you do your upgrades. As you have a 5 speed car, you can also upgrade to the "S" oil cooler which is about twice the size of the base unit, and is a simple bolt in swap for about $200 or so (parts at retail). The larger cooler is one of the biggest bang for the buck mods you can do for a base car.....

With getting it scanned to see what the codes are, guessing would be a total crap shoot. Get it scanned................ and, by-the-by, it can be scanned by any simple $30 unit to get the codes, you do not need anything fancy.

The M96 runds a bit rich at start up, to comply with 50 state emissions standards, it uses a secondary air injection pump for a short period after starting.

You need to pull the lower panel and have a look with a good flashlight; it there are signs of seepage from the weep hole on the bottom of the pump, you are in the market to replace it before it strands you somewhere not so nice.................

HI, Its looks like I have a leak similar to this. Does anyone have any experience of changing the tensioner seal. How do you lock the cams? What tooling is needed thanks Jetbox $600-$800 depending upon the source…………

We have the LN stat is several customer cars; I also have it in my personal car as well. The car will run quite a bit cooler at any given ambient temp than it would with the OEM stat (which only begins to open in the 185-190F range, but is not fully open until 205-210F), and will cool back down to a lower temp if it gets hot, such as being stuck in traffic for a bit (be aware that the dash gauge is notoriously inaccurate). One of the biggest advantages it brings is that it lowers the oil temps as well, which is good for both the engine and the oil. I would ignore the Porsche dealership's comments; after all, Porsche uses a similar stat in their "performance oriented" models like the GT2 and GT3..........

Oil level reading comes from a sensor in the oil sump. Either the sensor has gone bad, or the wiring pigtail leading out from it has become disconnected...........

I doubt it, but it will create more oil leaks than you ever imagined could exist............... Suggest you give Jake Raby a call, he once described pulling one of these that went flying around the shop when it released; seems to take a lot of force to dislodge it.

I'm not sure you are going to be happy about this, but, if your cam timing is off too much, the computer will see an incongruity between the crankshaft position and the cam position, which will make the DME confused, throwing off the injector pulse and ignition systems. If the car was able to run, it would promptly throw multiple codes relating to the position sensors; without being able to start it, the DME may not be getting to that point yet. Do you have a scanner capable of reading "real time" data from the DME? That should capture the position sensors issues as well............ In any case, the computer "resets" by simply removing the + battery cable for about 2 min............

Both were customer's cars, both appeared to be IMS bearing failures that led to other destruction; very similar to the earlier cars. One was under warranty, the other was not. Basically, if your engine has an IMS, you are at some level of risk; I have no knowledge of if the later cars fail any less or more, but they do fail. There is a reason why the new 9A1 is a “shaft-less” design engine……………….

My thoughts on the subject are very simple: The belt is cheap, but often not easy to find (a lot of auto parts stores don't seem to carry it in stock). If it breaks, you are stuck; it the M96 overheats, you could be screwed. Why take chances with it? Considering the potential downsides to a belt failure, we change them more frequently than the factory suggests. Pull the belt, check over the pulleys for noise and "wobble". It is simple and quick to do. If you find that the water pump or idlers are loose or noisy, take action and fix it. The idlers can be rebuilt (check the archives for info); a noisy water pump, idler, or alternator are not going to heal on their own.......................

A thought to keep in mind about the poly rib belt: It is one of the cheapest parts on the car (~$25 for the OEM unit), and it can be changed in about 20 min. by a total novice with simple hand tools. It also can both strand you and do a lot of damage to your engine if it fails. Change it regularly, and keep the old one in the car as a spare, just in case (they are not the easiest thing to find in a hurry)……….

The car can run (albeit poorly) with the cam off one tooth on the chain. But you have to remember that these are "interference engines", meaning that at some point in the system rotation, two (or more) components (valves and pistons) enter the same physical space. Obviously, you do not want that to happen at the same time. And, with VarioCam, the actual timing setting is changing while the engine is running. If the cam timing is off too much, the results are disastrous. The real issue is that you have four cams that all need to be working in concert with each other. I know of only one "proper" (e.g.: the way it is listed in the 13 volume OEM service manuals) method to reset cam timing once the system has been disturbed, and that is using one of these tool sets. I have heard of shops that have manufactured their own version of these, but the issue remains that you have to lock the engine in one position, and then set one cam, lock it down, and then adjust the other cam on the same head to match, and lock it down. Then you repeat the process on the other cylinder bank. If you have ever wondered what the strange green plugs are on the ends of the cam covers, they are for resetting the cams………………

First of all, what is in there is not a "timing belt", it is a poly rib belt that runs all the accessory drives. Make sure you have all the bolts out, and then give it a firm tug (there is a seal on the back that tends to cause it to stick to the bulkhead)............

Trying to do this by trial and error is going to be a nightmare. First of all, there are several speical tools required to time (or "allocate" in "Porsche speak") the cams. Below is the "basic" cam tool set, and none of this stuff is cheap ($600-800 for what you see). You also need to be very careful, if the timing goes off just a tad too much, pistons start hitting valves, and you have a new boat anchor..............