clord

Hmmm The US did not get the GT3 MKI, so, you may not get many US responses. UK guys?? It may help to know what tires you run on the street, and especially, what on the track? PAG changed the recommended pressures and tire sizes on the MKII that we did get in the US.

Welcome! Is your GT3 lower than factory stock....or, is it just that it is sitting on soft grass?

Hi fve....and Welcome! I own an '04 GT3 and they are Great Cars. I echo and support Loren's comments above. The GT3 gearbox is based on the box from the 993 GT2 twin turbo race car and is strong and well built......and, is rebuildable, unlike the Aisen (Asian sourced) boxes in the standard 996/986/997/987 cars. Porsche has disallowed Aisen to supply parts for them to rebuilders and would prefer to just replace them at factory option. You should have a look at the clutch and RMS while they are working on the box. Now would be the time to attend to any wear or leaks in that area. The GT3 gearbox is a very strong unit (if one does not abuse it) and should last a good long time. It is nearly identical to the boxes in the Turbo's and GT2's.

Another result can be more noise/rattling from the gear box at idle. This is the result of less damping of the individual cylinder firing pulses reaching the gearbox.

I notice that your car is C4. Given it's all wheel drive, you need to be concerned about any difference in rolling circumference in new tires, front to rear. The viscous differential driving the front axle senses rotational differences between the axles and begins to "increase lock" as the difference increases, up to a maximum of 40% lock. I would recommend that you maintain no more than 2-3% difference in new-tire rolling circumference, front to rear. Tire's actual dimensions can also vary among brands and models within brands, so, you should check the spec sheets for the exact tire model you are considering and compute the % difference in rolling circumference. In my own experience, with a '99 C4, I changed to Kinesis wheels and, after considereing fit and rolling size differences, decided to move up to what, at that time, was the '99 GT3 size tires/wheels. 225/40-18 and 285/30-18. This maintained front to rear handling balance, fit the car, and maintained the recommended front to rear rolling difference tolerance. By the way, although the Kinesis K28's looked good, were hub centric, and were light.....I managed to bend 3 out of the 4 wheels on real roads over a couple years. Each required a return to Kinesis for rim-half replacement and rebuild. Bottom line, although a lot of folks do it, there is additional consideration and responsibility involved in changing wheels and tires on car designed for a particular wheel/tire combo.

Gator....Yes, it seems to me that my counter shaft seal leak appeared quickly. At the time I was paranoid about RMS leaks because my buddie's GT3 (just three serial numbers older than mine) was having repeating problems with his RMS leaking and getting fixed. His re-leaked at the same time that I noticed my leak. We were at the track and his RMS leak had spread back along the engine case and all over the rear bumper due to air movement under the car at speed. Mine appeared just as a few drips at the bumper end of the case. When the oil is very clean, it's even harder to determine where it's coming from. As I said, the dealership took care of it all with no problems and I was delighted to hear that it was not the RMS. At 22K miles, my RMS has never leaked (fingers crossed). By the way, the water pump is one of the things the tech had to R&R to execute the fix....and, per the book, he replaced all the coolant with new......a nice benefit of the process.

Hi Gator...... I too have an '04 GT3 and I also had a small oil leak from the "front" (rearmost) end of the engine. It turned out to be a seal on the end of the countershaft where it terminates in the engine case. It was repaired on warranty with no problems. The tech had to remove the exhaust (I think) and quite a bit of the parts driven by the serpentine belt to get at the seal, but, did it all without dropping the engine. If your car is still on warranty, you should have no problems having it all covered under warranty. Let us know what you find out.

The DIY Loren refers to is for 996 GT3 intake screens...... Since you posted in the 997 GT3 forum, I'll assume you have a 997 GT3. Note that there will be differences in the 997 bumper and screens. If you DO have a 996 GT3, let me know. I can provide additional help AND have screens available.

Hi Dave.... I would jack it up at the standard, factory jack points. If you lift from the rear point on one side, the car is so stiff that the front will come off the ground as well and you can put a stand under the front. At the rear, you can then use a stand under the rear cross member near the lower control arm attachment point..........but......... Why do you want to put the car on stands in the first place? I wouldn't let the suspension hang down at full extension. I would want the dampers to sit at their normal ride height. If you are concerned about flat spotting the tires, that can happen, but, they will round out in the first few miles in the spring.

Hi Johnr.... The Mk II GT3 is a fine, sound, 911 with, arguably, the strongest normally aspirated 911 drive train of the 996 series. If normal service has been performed, I would not worry about the engine. You should, though, have a PIWIS scan of the ECU done to read out the number of over revs. Many over revs over a long time can indicate track, or other abuse. A leak down test can reveal any internal damage too. As for the pulling under acceleration, it can be caused by a number of things. As was said, uneven tire pressure is the easiest to check for. It can also be alignment (they are Very Sensitive to alignment), and, uneven tire wear or internal tire damage. GT3's can be darty, but, pulling on acceleration is a problem that can be fixed. Yes, the normal GT3 clutch action is noticably heavier than the standard 996. Let us know what you find and decide.

Hi My..... I don't have any personal experience with the possible drivability issues, but, for my world, the noise would be intolerable. I started mine with the mufflers off once, just to see/hear what it would sound like....and, I could not live with it.

Hi RJ.... There is a lot of disagreement on whether it's OK to lift the rear of a 911 (with the classic engine case, not the flat bottom as Loren points out) with a floor jack under the engine case. I've seen 911's lifted that way forever with no obvious damage......I've seen factory trained techs lift them that way.....even Turbos and recent GT cars that are heavier in the rear than the early cars. I've seen our local trusted certified tech list my own GT3 a few inches to get it on his lift. BUT, all that said, I don't lift my own car that way myself and don't ever plan to. Personally, I just think it's safer not to. If you have ever had an air cooled (or later GTcar) engine apart, you can envision the engine case structure. It's there to support the crank, barrels, heads, flywheel, etc. There is a nice mating flange to the two side of the case, but, it is definitely not a factory intended lift point. I've never seen any factory material recommending the case as a lift point. I can just imagine the lifting forces radiating through the case material from a localized lift/contact point on the bottom of the case. Also, Porsche has gone to great lengths to lighten the rear end of a 911 over the years (magnesium cases for engine and transmission come to mind) and I'll bet they have not added extra material to the engine case to accomodate lifting there. I'm sure others might have different opinions on the subject....this is just mine. That said, and given that I've not ever seen obvious damage as a result of lifting at the case, I'd say that no obvious damage has been done to your car.

Hi Dave.... As you know, the USA did not get the GT3 Mk I, so, you may not get experience from here, but, renntech is world wide, so maybe someone else can help. I do know that Porsche changed/re-tuned the spring and damper rates for the Mk II....the change might be for the better relative to the Mk I. As for the Bilstein PSS9, I have no personal experience but have heard that the quality is only average (you get what you pay for?). There are other after market options available. Motons have garnered a lot of positive comments in the States.

GT3.My..... I think that you are getting few responses to your problem, here, because it could be so many different things that might be the cause. As you know, we did not get the Mk I GT3 in the US. Do you have any ECU codes logged? My guess would be to start with the aftermarket intake system. Assure there are no vaccuum leaks after the MAF, first. Then assure the new intake resonance characteristics work with the factory resonance flap timing (run by the ECU). As mentioned above, check the intake cam timing adjuster and position/hall sensors. It would be interesting to watch the air/fuel ratios when your hesitations happen. Please let us know what you find!

Hi Doug.... I've found what I believe to be the screw, spring, and piston you describe on my own GT3 and in the parts listings. It is probably an oil pressure relief valve to control over pressure in the oiling system. If it went back in the way it came out, there should be no problem. You probably already know, there ARE two places that you drain oil from that engine. The sump drain in at the bottom of the crankcase a few inches rearward of the plug you mistakenly removed on the left side of case....and the other is the large plug that is screwed in vertically in the bottom of the oil tank on the right/passenger side of the engine.

Hi Flash.... Well, this is a subject that has been adressed time and again. You may find a lot of information with the search function. But, I'll share my own experience with you. All of my recent experience is with various Pagid models on steel brakes. They make the stock pads for GT3s and are the most often seen brand at the race track. In general, more agressive pads (higher coefficient of friction/higher heat tolerance) make even more noise than factory supplied street pads. Another generalization: quieter pads are softer and will produce even more dust. Bottom line, high performance steel brakes just make some (more or less) noise and make some dust. I have the factory supplied pads in my GT3 now for the street. They are actually an excellent compromise of noise/dust/stopping. Many have run those same pads on the track a few times a year with fine results.

Most all recent quick release hubs for steering wheels are keyed such that they only fit on one way. For instance, the '04 996 Cup cars have a coupling shaped like a non symmetric oval that will fit on only one way. The wheel stripe is always at 1200 if the alignment has been done correctly.

I did install the factory engine plate on my "flat bottom" '99C4 and know that the same plate will not fit on my GT3 motor. The factory option is specific to the flat bottom engine.

Such a factory option engine protection plate is available for the 'flat bottom', regular 996 engine. I am not aware of any such plate for the GT3/Turbo/GT2 motor. If it is, what is the part number?

Welcome! There is a track prepped '87 944 Turbo in my past as well.

I've used 3M Adhesive Remover for that job. If you get it very clean, it really will stick better. Be careful with fumes and skin contact to the 3M Adhesive Remover....it has a lot of xylene in it. It even eventually rots out latex gloves.....use nitrile gloves if you have them. Last time I re-afixed my spoiler lip, after re-gluing and riveting, I "sealed" the seam between the bumper and spoiler with a long length of tough black electrical tape. My hope was that it would keep out a lot of the gravel and sand that can jamb into the joint between the spoiler and bumper and help "pry" it open at speed. It seems to be working.

Any screen over the air intakes will restrict air flow somewhat, but, I don't believe that either the Cup car screens nor the Cargraphic will restrict the flow enough to make any difference to a moving car. They both will stop flying junk larger than about 1/4 of an inch. In my opinion, the removal of the black plastic frame/ducting behind the holes in the bumper may actually have a larger effect on the air flow....but, that is only my own speculation from standing there looking at it on the garage floor and trying to deduce what it does. Certainly, even the factory feels it's ok to remove the frame on the racing Cup Car....but, they expect that the Cup Car will be moving fairly briskly through the air!....not idling through summer traffic. As far as the aesthetics of the screen install.....yeh, that bothered me too. When you remove the black frame you expose some locating slots/holes on the inside edge of the intake holes. Most folks use tie wraps/zip ties through those holes to help locate the screens as well as a big "rope" of urethane glue all around the periphery of each hole. I wouldn't think twice about doing that on a track-only car....but..........

Izard.... i've experimented with inlet protective screens on my '04 996 GT3. I tried both the factory cup car screens that Carnewal and TRG sells...and with the German screens from Cargraphic. In the end, I've decided not to put them on. Both sets require me to remove and not use the black plastic frame that mounts inside the bumper and stiffens the three inlet holes. It also guides airflow, somewhat, to the radiators. The screens from both sources replace that frame and require you to glue and/or tie wrap the screens to the inside of each inlet. To me, it just isn't a clean installation. By the way, although I sold the Cup screens, but, I still have the Cargraphic screens and would be willing to sell. I really have no idea, though, if they will even fit on a 997 G3.

Correct....and, if I remember correctly, the GT3 Mk II RS was delivered with a single mass flywheel.

Hi Bruno...... Now I know what you are talking about...but, still unable to answer your original question. You are a lucky guy to have an Ur RS2! I see now that Porsche must have supplied the hubs (with their bolt circle) along with the Porsche badged Brembo brakes. I used to own a 1991 Audi 200 20V TQ...and, yes that motor is strong and powerful....and with Porsche's upgrades, it must be a hoot to drive.